1182 Treffer:
Mission Possible  
Eine Ausstellung zum 50. Geburtstag des Instituts für Weltraumforschung der Österreichischen Akademie der Wissenschaften  
Touching Mars - Landesonden auf dem Roten Planeten  
Ein Vortrag im Rahmen der Vortragsreihe "Facetten der Physik" der Universität Graz  
Sommerschule Alpbach 2021  
13.-22. Juli 2021
Die Sommerschule Alpbach ist eine Ideenfabrik und Kaderschmiede für die europäische Raumfahrt. Alljährlich ermöglicht sie 60 jungen WissenschafterInen und IngenieurInnen vertiefende Studien zu jeweils verschiedenen Themen der Weltraumforschung.
 
CHEOPS entdeckt einzigartigen Exoplaneten  
In Nature Astronomy präsentiert ein internationales Team, dem auch das Grazer Institut für Weltraumforschung (IWF) der Österreichischen Akademie der Wissenschaften angehört, ungewöhnliche Details eines Planeten im Sternensystem Nu2 Lupi, die das ESA-Weltraumteleskop CHEOPS durch Zufall ans Licht gebracht hat. Der helle, sonnenähnliche Stern mit dem Namen Nu2 Lupi befindet sich in knapp 50 Lichtjahren Entfernung von der Erde im Sternbild Lupus (Wolf). Bei der Beobachtung seiner beiden innersten Planeten - b und c – im Frühjahr 2020 entdeckte das Weltraumteleskop CHEOPS unerwartet den dritten bekannten Planeten des Systems. "Gleichzeitig mit Planet c zog auch Planet d am Stern vorbei, obwohl seine Bahn deutlich weiter außen im Sternensystem verläuft", schildert IWF-Gruppenleiter Luca Fossati, Mitautor der Studie. "Da langperiodische Exoplaneten so weit von ihren Sternen entfernt kreisen, sind die Chancen, sie während eines Transits zu sehen, unglaublich gering," setzt Fossati fort. Der Fund von CHEOPS ist also ein kleines Wunder. Zum ersten Mal wurde ein Exoplanet mit einer Periode von mehr als 100 Tagen gesichtet, der an einem Stern vorbeizog, der hell genug ist, um ihn mit bloßem Auge zu sehen. Bei einem Transit blockt der Planet einen winzigen Teil des Lichts ab, wenn er vor seinem Stern vorbeizieht. Dieser Lichtabfall führte das CHEOPS-Team auch zu der außergewöhnlichen Entdeckung von Nu2 Lupi d. Transits bieten eine wertvolle Gelegenheit, um die Atmosphäre, Umlaufbahn, Größe und das Innere eines Planeten zu untersuchen. Die meisten bisher entdeckten Exoplaneten mit langer Periode wurden in der Nähe von Sternen gefunden, die zu schwach sind, um detaillierte Beobachtungen zu ermöglichen. Nu2 Lupi ist jedoch hell genug und damit ein äußerst attraktives Ziel für weitere Beobachtungen. Die hochpräzisen Messungen von CHEOPS ergaben, dass Planet d etwa den 2,5-fachen Erdradius hat, seinen Stern in etwas mehr als 107 Tagen umrundet und seine Masse 8,8-mal so groß wie die der Erde ist. Anhand der neuen Daten konnte das Wissenschaftsteam die mittlere Dichte der Planeten genau bestimmen. Man fand heraus, dass Planet b hauptsächlich aus Gestein besteht, während die Planeten c und d vermutlich große Mengen an Wasser enthalten, das von einer kleinen Menge Wasserstoff und Helium umhüllt ist. Tatsächlich beherbergen die Planeten c und d weit mehr Wasser als die Erde: Ein Viertel ihrer Masse besteht aus Wasser, verglichen mit weniger als 0,1 % bei der Erde. "Unsere Berechnungen zeigen, dass die Gashülle der Planeten schon bei ihrer Entstehung vorhanden war", fügt Mitautor Andrea Bonfanti vom IWF hinzu. "Obwohl keiner dieser Planeten bewohnbar wäre, macht ihre Vielfalt das System noch spannender und bietet eine großartige Perspektive für die Zukunft", so Fossati. Weitere Informationen finden Sie in einer Presseaussendung der ESA.  
Working with us  
General resources:  Förderprogramme der ÖAW FWF Programme ÖAW Jobs Opportunities to work with us as Summer student: FFG Talente Praktika Opportunities to work with us as PhD student: DOC Fellowship Programme of the Austrian Academy of Sciences FWF Einzelprojekte Opportunities to work with us as PostDoc: Marie Skłodowska Curie Individual Postdoctoral Fellowships  ESPRIT-Programm Lise-Meitner-Programm Hertha-Firnberg-Programm ERC Starting Grant International Exchange grants: Internationale FWF Programme Heisenberg-Programm Royal Society of Edinburgh  
MMS/ASPOC Data Analysis  
Missions MMS Projekte FFG-847969 MMS ASPOC The Active Spacecraft Potential Control (ASPOC) aboard Magnetospheric Multiscale (MMS) generates beams of indium ions at energies of order 4-12 keV and variable currents of up to 70 μA in order to limit positive spacecraft potentials within several volts and, e.g., thereby improve the measurements obtained by the instruments FPI, HPCA, ADP, and SDP (Torkar et al., 2014). There are two ASPOC per MMS spacecraft, each unit contains four ion emitters and one emitter per instrument is operated at a time. PLASMA DENSITY DERIVATION By determining statistically the photoelectron curve for different science phases, using, plasma current, spacecraft potential, and ASPOC current, plasma density estimation is performed assuming ASPOC current to be a bias current of the spacecraft potential using the method by Andriopoulou et al. (2015). The code (derivation algorithm) is IDL based and requires spedas to be installed. The usage is given in (ASPOC Iphoto). The users can run the code to derive the photo electron curve themselves.  For Phase 1 and 2 the derived input parameters for photo electron curves are given in (ASPOC Iphoto curves). The photo electron curves are then used to calculate the density. For shorter burst mode intervals a local photo curve might improve the density estimation. The photocurve local script can then be used (when ASPOC is off). SOLAR WIND DENSITY PRODUCT The solar wind is a weakly compressible turbulent plasma. Although the compressible  fluctuations (i.e. density, magnetic field magnitude) are small with respect to the transverse fluctuations they represent a non-negligible fraction of the fluctuation powers, and become increasingly important at sub ion scales. By using the spacecraft potential to estimate the density in the solar wind much higher time resolutions are possible when compared to the direct measurement. This allows much smaller scales to be investigated than are typically possible with particle detectors. Our solar wind density product uses the plasma density derivation library (see above) to calibrate to density and also removes spin tones in the data. The data archive contains both fast survey mode data sampled at 32Hz and burst mode data sampled at 8kHz. The data can be accessed here. A quick reference guide is also available and the data is described in detail in the paper: Roberts et al., JGR (2020). In the archive, two data formats are available: an IDL .sav format which can be opened with the IDL restore command and an ASCII format. AC ELECTRIC FIELD CORRECTION Strong electric fields have been shown to have an effect on the spacecraft potential causing a larger current from the spacecraft. In effect accelerating more photoelectrons from the surface that ordinarily would not have escaped the potential well of the spacecraft. In these circumstances the electric field effects can have a stronger effect on the spacecraft potential than the density meaning that it can be misleading to use the density estimation. A correction can be performed on the data as discussed in Roberts et al. (2020), so that the density estimation can still be used. An IDL script detailing the method and examples are given here. This routine requires spedas to be installed. MMS/ASPOC LINKS Instrument side: ASPOC/MMS@IWF MMS side at IWF: MMS@IWF MMS science data center: MMS@SDC  
Martin August Reiss  
Dr. Martin August Reiss Scientist T +43 (316) 4120 - 637 Martin.Reiss(at)oeaw.ac.at Room 2.b.10 Curriculum Vitae Research Interests I am a postdoctoral researcher at the Space Research Institute of the Austrian Academy of Sciences in Graz, Austria. My research focuses on ambient solar wind modeling and space weather forecasting. I am currently studying interdisciplinary data science methods in combination with multi-spacecraft observations to advance the capabilities of coronal and solar wind models. Experience since 2020    Postdoctoral Researcher, Space Research Institute of the Austrian Academy of Sciences, Graz 2018-2020   Schrödinger Fellowship, NASA Goddard Space Flight Center, Greenbelt, USA Education 2014 - 2017   Ph.D. in Natural Sciences (with distinction), University of Graz, Austria 2012 - 2014   M.Sc. in Theoretical and Computational Physics (with distinction), University of Graz, Austria Community Service since 2021   Moderator of the COSPAR ISWAT cluster Ambient Solar Magnetic Field, Heating and Spectral Irradiance since 2019   Team lead of the Coronal Hole Boundary Working Team in the COSPAR ISWAT initiative since 2019   Team lead of the Ambient Solar Wind Validation Team in the COSPAR ISWAT initiative since 2016   Reviewer for the journals: AGU Space Weather, Journal of Space Weather and Space Climate, and PLOS One On the Web NASA/ADS ORCID Google Scholar Researchgate YouTube  
Wer wir sind  
Das Grazer Institut für Weltraumforschung (IWF) beschäftigt sich seit 50 Jahren mit der Physik von Weltraumplasmen und den Atmosphären von Planeten innerhalb und außerhalb unseres Sonnensystems. Mit rund 100 Mitarbeiterinnen und Mitarbeitern aus zwanzig Nationen ist es eines der größten Institute der Österreichischen Akademie der Wissenschaften (ÖAW). Beheimatet ist das Institut im Victor Franz Hess-Forschungszentrum der ÖAW im Süden von Graz. Am Observatorium Lustbühel betreibt es eine Satelliten-Laserstation, die zu den besten der Welt zählt. Das IWF ist das einzige Institut in Österreich, das weltraumtaugliche Messgeräte im großen Rahmen entwickelt und baut. Die gewonnenen Daten werden am Institut wissenschaftlich analysiert und physikalisch interpretiert. Die Schwerpunkte dabei sind der Bau von Magnetometern und Bordcomputern sowie die Laserdistanzmessung zu Satelliten und Weltraumschrott. Die wissenschaftliche Datenauswertung dient vor allem der Untersuchung dynamischer Prozesse in der Weltraumplasmaphysik und der Erforschung der oberen Atmosphäre von Planeten und Exoplaneten – also Planeten außerhalb unseres Sonnensystems. Der Weltraum wird seit mehr als 60 Jahren mithilfe von Satelliten erforscht und gibt uns noch immer sehr viele Rätsel auf. Seit Beginn der 80er Jahre trug/trägt das IWF zu über 40 internationalen Weltraummissionen mit  mehr als 100 Messgeräten bei. Derzeit ist das Institut an 23 Projekten beteiligt, die von der Europäischen Weltraumorganisation ESA, der NASA oder nationalen Weltraumagenturen in Japan, Russland, China und Südkorea geleitet werden. Die Missionen reichen von Satellitenflotten im erdnahen Weltraum über die Sonnenbeobachtung bis zur Erforschung von Planeten wie Merkur, Jupiter und extrasolaren Planeten. Vom Bau der Messgeräte bis zur Auswertung der Daten beträgt die Projektlaufzeit 10-30 Jahre. Während die Ernte der abgeschlossenen Missionen bereits eingefahren wurde, analysieren die Wissenschaftler/innen eifrig die Daten der laufenden Missionen und im Labor werden die Sensoren und Messgeräte für zukünftige Missionen entwickelt.  
Planetare Atmosphärenflucht  
Die langfristige Entwicklung von Planetenatmosphären und damit die beobachtete Radiusverteilung wird maßgeblich durch Atmosphärenflucht (oder "Verlust") beeinflusst. Dies ist ein Prozess, bei dem atmosphärisches Gas die Gravitationsquelle des Planeten verlässt und sich im Weltraum verteilt. Bei Planeten, die in der Nähe ihres Muttersterns kreisen, erwärmt die Absorption starker energiereicher Strahlung (d.h. Röntgenstrahlen, extremes ultraviolettes und ultraviolettes Licht) die obere Atmosphäre, die sich möglicherweise hydrodynamisch ausdehnt und zum Verlust führt. In extremen Fällen füllt die expandierende Atmosphäre ihren Roche-radius und ein großer Teil des atmosphärischen Gases geht im All verloren - mit katastrofalen Folgen für die Planetenatmosphäre. Der Verlust der Atmosphäre kann am besten untersucht werden, indem die Atmosphären sehr nahe beieinander liegender Planeten beobachtet werden. Aus diesem Grund sind extrasolare Planeten (Exoplaneten), die vor ihren Muttersternen vorbeiziehen, ideale Laboratorien, um dieses Phänomen zu untersuchen. Es gibt zwei Möglichkeiten, den atmosphärischen Verlust zu beobachten: ultraviolette Beobachtungen vom Atmosphären von Exoplaneten in der Nähe des Muttersterns und Untersuchung der Auswirkungen des Verlust auf die beobachteten Exoplaneten. Mitglieder der Exoplanetengruppe arbeiten aktiv an Beobachtungen und Modellen, um den Verlust einzuschränken. Daten von HST, CHEOPS, CUTE, PLATO und ARIEL sind der Schlüssel für diese Aufgabe.  
Macao Science 1  
Macao Science 1 wurde vom State Key Laboratory of Lunar and Planetary Science an der Macau University of Science and Technology (MUST) entwickelt und wird mit Unterstützung der China National Space Administration (CNSA) und der lokalen Regierung realisiert. Es ist der weltweit erste und einzige wissenschaftliche Erkundungssatellit, der in einer äquatornahen Umlaufbahn platziert wird, um das geomagnetische Feld und im Speziellen die Südatlantische Anomalie vom Weltraum aus zu erforschen. Der Start ist für 2023 geplant. Die Südatlantische Anomalie ist ein Bereich mit einem deutlich abgeschwächten geomagnetischen Feld und einer damit verbundenen erhöhten Strahlungsaktivität. Ihr Zentrum liegt vor der Küste Brasiliens. Der innere der beiden Van-Allen-Strahlungsgürtel reicht am Äquator bis etwa 700 Kilometer an die Erde heran. Im Bereich der Südatlantischen Anomalie kommt er ihr deutlich näher. Gemeinsam mit der im Jahr 2013 gestarteten Satellitenmission SWARM der ESA soll die sich erweiternde und vertiefende Südatlantische Anomalie genauer als bisher erforscht und vermessen werden. Macao Science 1 soll dem Team am Boden hochpräzise, hochauflösende und langzeitige vektorielle Magnetfelddaten und Informationen über die hochenergetischen Teilchen in der Region liefern. Die Gesamtlänge des Satelliten beträgt mehr als acht Meter und sein Gewicht etwa 500 Kilogramm. Die Magnetfeldsensoren werden auf einem 3,7 Meter langen, nicht-magnetischen Ausleger mit einer optischen Plattform montiert. Die wissenschaftliche Nutzlast besteht aus einem Hochenergie-Teilchendetektor, einem Star Tracker, einem Fluxgate-Magnetometer und einem Quanteninterferenz-Magnetometer (CDSM), dessen Sensor und sensornahe Elektronik vom IWF in Kooperation mit dem Institut für Experimentalphysik der Technischen Universität Graz beigesteuert wird (wie schon für CSES-1 und CSES-2). Die Entwicklung der Prozessor- und Energieversorgungselektronik des CDSM sowie dessen Gesamtintegration und Test erfolgen durch das Harbin Institute of Technology, Shenzhen.  
Wie wird das Weltraumwetter?  
Künstliche Intelligenz verbessert Vorhersage von Sonnenstürmen  
FORESAIL-2  
FORESAIL ist ein CubeSat-Programm, das von der Aalto-Universität im Rahmen des Finnischen Exzellenzzentrums für nachhaltige Raumfahrt durchgeführt wird. Das FORESAIL-Programm umfasst drei CubeSats, die in den Jahren 2020 bis 2025 gestartet werden sollen. Ziel ist die Demonstration qualitativ hochwertiger wissenschaftlicher Weltraumbeobachtungen bei gleichzeitiger Vermeidung von Weltraummüll durch sicheres Verlassen der Umlaufbahn. FORESAIL-2 ist die zweite Mission in diesem Programm. Der Start ist für das Jahr 2023 geplant. In einer geostationären Transferumlaufbahn (GTO) soll der CubeSat die harte Strahlung im Van-Allen-Gürtel mit kostengünstigen Komponenten und einem fehlertoleranten Software-Ansatz überleben. Darüber hinaus soll ein Coulomb-Widerstandsexperiment das sichere Verlassen aus Umlaufbahnen mit hohem Apogäum demonstrieren. Das wissenschaftliche Ziel dieser Mission ist es, die Variabilität von ULF-Wellen (Ultra Low Frequency) in der inneren Magnetosphäre und ihre Rolle bei der Anregung von Teilchen zu charakterisieren. Dieses Ziel soll mit Hilfe eines Relativistischen Elektronen- und Protonenexperiments (REPE) und eines Magnetfeldexperiments erreicht werden. Das IWF steuert in Kooperation mit dem Institut für Elektronik der Technischen Universität Graz ein Magnetometer auf Basis des neu entwickelten Magnetometer-Frontend-ASICs (Next Generation MFA) bei. Finanziert wird der Grazer Beitrag von der Österreichischen Forschungsförderungsgesellschaft (FFG) im Rahmen des nationalen Weltraumprogramms ASAP.  
Exoplaneten  
Leitung Team  
Andreas Krenn  
Andreas Krenn, MSc PhD Student T +43 (316) 4120 - 646 Andreas.Krenn(at)oeaw.ac.at Room E.b.4  
Urlaub im All - Massentourismus oder Luxustraum?  
Ein Vortrag im Rahmen des Science-Programms der Wiener Volkshochschulen  
Christian Moestl  
Dr. Christian Möstl Scientist T +43 (316) 4120 - 519 Christian.Moestl(at)oeaw.ac.at Room 2.b.10 Curriculum Vitae Publications Twitter Research Interests Solar coronal mass ejections (Exo-)planetary space weather Planetary magnetospheres Real-time space weather prediction Interplanetary CubeSats Career Summary 2009              Ph.D. Physics, University of Graz, Austria 2010              PostDoc, Institut für Weltraumforschung, ÖAW, Austria 2011              PostDoc, University of Graz, Austria 2011-2012   Marie Curie fellow, University of California, Berkeley, CA, USA 2012-2013   Marie Curie fellow, University of Graz, Austria 2014-2017   Working package leader (EU HELCATS), University of Graz, Austria since 2014    Research Associate, Institut für Weltraumforschung, ÖAW, Austria since 2014    Research project PI, Institut für Weltraumforschung, ÖAW, Austria Publications Refereed Articles: 87 (First Author: 15) Citations in SCI: 2743 (Hirsch Index: 30) Selected List: Prediction of the In Situ Coronal Mass Ejection Rate for Solar Cycle 25: Implications for Parker Solar Probe In Situ Observations Möstl, C., A.J. Weiss, et al. (2020), Astrophys. J. Forward Modeling of Coronal Mass Ejection Flux Ropes in the Inner Heliosphere with 3DCORE Möstl, C., T. Amerstorfer, et al. (2018), Space Weather Strong coronal channelling and interplanetary evolution of a solar storm up to Earth and Mars Möstl, C., T. Rollett, et al. (2015), Nat. Comm. Observations of an extreme storm in interplanetary space caused by successive coronal mass ejections Liu, Y.D. et al. (2014), Nat. Comm. Modeling observations of solar coronal mass ejections with heliospheric imagers verified with the Heliophysics System Observatory Möstl, C. et al. (2017) Space Weather ElEvoHI: A Novel CME prediction tool for heliospheric imaging combining an elliptical front with drag-based model fitting Rollett, T., C. Möstl, et al. (2016), Astrophys. J. Multi-point shock and flux rope analysis of multiple interplanetary coronal mass ejections around 2010 August 1 in the inner heliosphere Möstl, C. et al. (2012), Astrophys. J. Recognition 2016   Arne Richter Award for Outstanding Young Scientists, European Geophysical Union 2011   Josef Krainer Award for young researchers, Austria 2008   Award of the governor of Styria for young researchers, Austria 2008   Young Scientist Outstanding Poster Presentation Award, European Geophysical Union Projects EU: Marie Curie EU: HELCATS FWF: P 26174-N27 FWF: P 31521-N27 FWF: P 31659-N27 On the Web ADS Figshare GitHub Google Scholar ORCID Twitter Young Science Youtube  
Rumi Nakamura  
Doz. Rumi Nakamura Group Leader T +43 (316) 4120 - 573 Rumi.Nakamura(at)oeaw.ac.at Room 2.b.5 Publications Research Interests Space plasma physics, based on data analysis from satellites and ground-based measurements Career Summary 1990-1991    Research Associate, National Institute of Polar Research, Tokyo, Japan 1991-1993    Research Associate, NASA Goddard Space Flight Center, USA 1993-1998    Assistant Professor, Solar-Terrestrial Environment Laboratory, Nagoya University, Japan 1998-2001    Senior Scientist, Max-Planck-Institut für extraterrestrische Physik, Germany since 2001     Group Leader, Institut für Weltraumforschung, ÖAW, Austria since 2010     Lecturer, Institute of Physics, University of Graz, Austria Publications Refereed Articles: 426 (First Author: 45) Citations in SCI: 14813 (Hirsch Index: 60) Recognition 2005    Woman Researcher of the Month, Ministry for Transport, Innovation & Technology, Austria 2005    TanakadateAward, Society of Geomagnetism & Earth, Planetary & Space Sciences, Japan 2011    Full Member, International Academy of Astronautics 2014    Julius-Bartels Medal, European Geophysical Union 2018    Member, European Academy of Sciences and Arts 2019    Corresponding Member, Austrian Academy of Sciences 2019    Member of Academia Europaea Editorial/Advisory Boards 2007-2009    Associate Editor, Geophysical Research Letters 2007-2013    Editor, Annales Geophysicae 2008-2012    Associate Editor, Journal of Geophysical Research 2011-2013    International Space Science Institute, Science Committee 2015-2017    ESA Solar System Exploration Working Group since 2017     International Academy of Astronautics, Board of Trustee, Basic Science Section Member since 2019     ESA, Voyage 2050 senior committee Projects FWF: P 23862-N16 FWF: I 429-N16 FWF: I 2016-N20 FP7: ECLAT FFG: 847969 - MMS-ASPOC FFG: 873685 - MMS-ASPOC 2  
Luca Fossati  
Doz. Luca Fossati Group Leader T +43 (316) 4120 - 601 Luca.Fossati(at)oeaw.ac.at Room E.b.3 Publications Research Interests My research interests span from exoplanets to stars. In the exoplanet field my research concentrates mostly on the observational and theoretical study of planet atmospheric escape and of the star-planet interaction phenomenon. My research covers also the characterisation of planetary atmospheres. In the stellar field my research interests cover the photometric and spectroscopic characterisation of stellar atmospheres, the study of stellar evolution, and the detection of magnetic fields for stars across the whole Hertzsprung-Russell diagram. Career Summary 2009-2012     Postdoctoral Research Assistant at the Open University, UK since 2012      Research visiting fellow, Open University, Milton Keynes, UK 2012-2014     Postdoc, Argelander Institut für Astronomie, University of Bonn, Germany 2014-2015     Alexander von Humboldt fellow, Argelander Institut für Astronomie, University of Bonn, Germany since 2015      Group Leader, Institut für Weltraumforschung, ÖAW, Austria Publications Refereed Articles:  193 (First Author: 27) Citations in SCI:  5008 (Hirsch Index: 38) Projects FFG: TAPAS4CHEOPS FFG: ACUTEDIRNDL  
Manfred Steller  
Dr. Manfred Steller Group Leader T +43 (316) 4120 - 541 Manfred.Steller(at)oeaw.ac.at Room 1.a.3 Research Interests Space instrumentation Micro Electrical and Mechanical Systems (MEMS) Automation and control technology Career Summary since 1984    at Institut für Weltraumforschung, ÖAW, Austria 1989-2000    Freelancer at the Institute for Applied Systems Technology, Joanneum Research, Austria since 2002    Group Leader, Institut für Weltraumforschung, ÖAW, Austria Publications 39 Refereed Articles (First Author: 2) Project Participation Co-Principal Investigator: Solar Orbiter (RPW) Co-Investigator: Cassini/Huygens (ACP) Magnetospheric MultiScale (EDI) Board Member: CHEOPS (BEE) Technical Manager: Phobos (TAUS) Austromir (DATAMIR) Rosetta (MIDAS) CoRoT (BEX) PLATO (RDCU) SMILE (SXI) ATHENA (WFI)  
Werner Magnes  
Dr. Werner Magnes Deputy Director, Group Leader T +43 (316) 4120 - 562 Werner.Magnes(at)oeaw.ac.at Room 1.d.8 Research Interests Design and development of space-borne magnetic field instruments Digital signal processing Career Summary 1994             Diploma in acoustic and electrical engineering, Graz University of Technology, Austria 1999             PhD, Graz University of Technology, Austria since 1992   at Institut für Weltraumforschung, ÖAW, Austria since 1996   Teaching at Graz University of Technology, Austria since 2002   Group Leader, Institut für Weltraumforschung, ÖAW, Austria since 2015   Deputy Director, Institut für Weltraumforschung, ÖAW, Austria Publications 147 Articles (First Author: 5, Refereed Articles: 136) Project Participation Co-Investigator: Magnetometer Rosetta Lander DoubleStar Venus Express BepiColombo / MPO and MMO Magnetospheric Multiscale JUICE / J-MAG Solar Orbiter Comet Interceptor Technical/Project Manager: BepiColombo / MMO Magnetometer Front-end ASIC Chimag and SEGMA ground based networks China Seismo-Electromagnetic Satellite (CSES) / Coupled Dark State Magnetometer GEO-KOMPSAT-2A / Service Oriented Spacecraft Magnetometer Other Missions and Projects involved: Themis Cluster  
Untersuchung exoplanetarer Atmosphären mit ARIEL  
Ein Webinar im Rahmen des Science-Programms der Wiener Volkshochschulen  
SMILE  
SMILE (Solar wind Magnetosphere Ionosphere Link Explorer) ist eine gemeinsame Mission der Europäischen Weltraumorganisation ESA und der Chinesischen Akademie der Wissenschaften (CAS), die die Wechselwirkung zwischen dem Sonnenwind und der Erdmagnetosphäre näher erforschen soll. Der Start ist für 2024 geplant. Obwohl bereits viele Satelliten - wie zum Beispiel Cluster, MMS und STEREO - die Sonne und ihren Einfluss auf die Erde beobachten, ist keine dieser Missionen in der Lage, diese Wechselwirkung in ihrer Gesamtheit zu betrachten. Vielmehr werden nur einzelne, lokale Prozesse und individuelle Wettergeschehnisse untersucht. SMILE wird diese Lücke füllen und unsere Magnetosphäre auf globaler Ebene erforschen. Damit erwartet man sich ein besseres Verständnis der Beziehung zwischen Sonne und Erde. Das IWF ist mit Hardware am Soft X-ray Imager (SXI) und wissenschaftlich am Magnetometer (MAG) beteiligt. Weitere Informationen zu SMILE findet man bei der ESA.  
Helmut Lammer  
Leitung  
Woher weht der Sonnenwind?  
In einer Studie, die soeben im Astrophysical Journal erschienen ist, hat ein internationales Team unter der Leitung des Instituts für Weltraumforschung (IWF) der Österreichischen Akademie der Wissenschaften erstmals ermittelt, welche Unterschiede bei der automatisierten Lokalisierung des Ursprungs des Sonnenwindes auftreten können.  
Home  
Interaction of escaping atmospheres of close-orbit exoplanets with stellar winds Principal Investigator Dr. Maxim Khodachenko E-Mail maxim.khodachenko[at]oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 01.05.2016 Project duration Start: 01.08.2016   End: 31.12.2020 Scientific field(s) 103 (Physics, Astronomy): 100%  
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Energy transport and release in the solar atmosphere: effects of background flow (Energietransport in der Sonnenatmosphäre: Hintergrundflüsse) Principal Investigator Dr. Maxim Khodachenko E-Mail maxim.khodachenko[at]oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 01.05.2014 Project duration Start: 01.08.2014   End: 30.09.2017 Scientific field(s) 103 (Physics, Astronomy): 100%  
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Manifestations of deep convection in stellar photometry (Manifestationen von Tiefenkonvektion in stellarer Photometrie) Principal Investigator Dr. Maxim Khodachenko E-Mail maxim.khodachenko[at]oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 01.03.2013 Project duration Start: 01.08.2013   End: 31.07.2017 Scientific field(s) 103 (Physics, Astronomy): 100%  
Lehre  
Mitarbeiterinnen und Mitarbeiter des IWF sind als Lehrbeauftragte an folgenden Universitäten und Fachhochschulen tätig: Universität Graz Technische Universität Graz Universität Wien Technische Universität Braunschweig FH Joanneum FH Wiener Neustadt Seit Herbst 2011 wird das Masterstudium "Space Sciences and Earth from Space" der NAWI Graz angeboten. Den Studierenden wird eine technisch-naturwissenschaftliche Ausbildung auf dem Gebiet der Weltraumwissenschaften und ihrer Anwendungen in drei einander ergänzenden Vertiefungsfächern: Solar System Physics Satellite Systems Earth System from Space Das Studium entspricht dem Prinzip der forschungsgeleiteten Lehre und profitiert dabei von der Bündelung der standortspezifischen Kompetenzen der Universität Graz, der TU Graz, des Instituts für Weltraumforschung der ÖAW und der Forschungsgesellschaft Joanneum Research. Die Sommeruniversität "Graz in Space" wird gemeinsam von der Kommission für Astronomie und dem Institut für Weltraumforschung der ÖAW sowie dem Institut für Physik der Universität Graz veranstaltet und findet im Zwei-Jahres-Rhythmus unter der wissenschaftlichen Leitung von Helmut Rucker statt.  
Software-Partnerschaft  
As an Academic Partner of Visual Paradigm, Austrian Academy of Sciences is issued software tools for educational use, which cover UML, BPMN, Agile story mapping, etc.  
Comics 4 Kids  
Die ÖAW hat vier neue Wissenschaftscomics für Kinder herausgebracht. In Band 8 geht es um "Das Geheimnis der Sternwarte".  
Manfred Stachel  
Dipl.-Ing. Manfred Stachel Engineer T +43 (316) 4120 - 412 Manfred.Stachel(at)oeaw.ac.at Room 2.d.6  
Maxim Khodachenko  
Dr. Maxim Khodachenko Scientist T +43 (316) 4120 - 661 Maxim.Khodachenko(at)oeaw.ac.at Room E.c.4 Curriculum Vitae Publications Research Interests Extrasolar planets: Stellar-planetary interactions, habitability, search algorithms, exoplanetary magnetospheres Planetary Magnetospheric/atmospheric/surface physics: Io-Jupiter electrodynamic interaction, Mercury, Earth paleo-magnetosphere, exoplanets Solar/stellar physics: Solar/stellar activity and winds; Dynamics of solar/stellar plasma-magnetic structures; flares; prominences; CMEs; waves Radio astronomy: radiation mechanisms, data analysis Plasma physics: MHD and kinetic theories in application to astrophysical and aerospace problems Laboratory astrophysics: experimental study of space plasma processes Scientific research management: Project coordination; EU FP6, FP7, Horizon 2020; European Research Area (ERA) and Research Infrastructures Current research summary (since 2015) CAREER SUMMARY 1989-1999: Research Scientist, Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod, RU; (full-time) 1999-2001: Senior Research Fellow, Max-Planck-Institut für Extraterrestrische Physik, Garching, DE (fellowship; full-time) 2001-2014: Postdoctoral Research Fellow, Space Research Institute, Austrian Academy of Sciences, Graz, Austria (full-time) Since 2014: Research Scientist, Space Research Institute, Austrian Academy of Sciences, Graz, Austria (permanent; full-time) Project FP7: IMPEx FP7: JRA3-EMDAF in Europlanet RI FP7: ETFLA in ASTRONET FWF: S11606-N16 I FWF: S11606-N16 II FWF: I2939-N27 FWF: P25640-N27 FWF: P25587-N27 FWF: P 21197-N16  
Final Report  
Information on the development of the research project Overall scientific concept and goals:           A distinctive feature of hot close-orbit exoplanets consists in the expansion and outflow of their upper atmospheres, ionized and heated by the UV and soft X-ray radiation of the parent stars. The outflowing partially ionized atmospheric material, interacting with the surrounding stellar wind plasma, forms a dynamical plasmasphere around the planet. Such plasmaspheres are a new object for astrophysics, which involves the photochemistry and collisional hydrodynamics of the planetary gas, as well as the specifics of the fast and collisionless stellar wind. The study and detailed modelling of the dynamics and structure of plasmaspheres of hot exoplanets is of high interest for the interpretation of the measured stellar radiation spectra absorbed by transiting exoplanets, as it significantly expands the possibilities for probing of a variety of physical and chemical characteristics of both the planets and their stars. Since 2003, the modeling of physical processes related with the mass loss of upper exoplanetary atmospheres passed a long way of development, from simple quasi-empirical analytical estimations to complex kinetic and (magneto)hydrodynamic numerical  codes. The achieved level of modelling enables interpretation of the measured transit absorption in the lines of various elements and characterizing of the composition and dynamics of the escaping atmospheres of close-orbit ‘hot Jupiters and Neptunes’. At the same time, while the task of revealing of atmospheric composition is solved relatively straight forward - by the detection of particular spectral lines, which change their intensity during the planet transits, the characterization of escaping atmospheric flows and quantifying of the abundances of detected elements depend on the quality and capacity of the applied computational models and the adopted assumptions. On the other hand, the ability of numerical model to reproduce observations serves as verification of the model itself, validating its scientific consistency.           The project was aimed at the investigation and characterization of different regimes of the exoplanetary and stellar winds interaction, paying attention to their observational manifestations and the possible role of planetary magnetic field. Special focus was made on the simulation of complex dynamic environments of exoplanets, and interpretation of the real transmission spectroscopy data acquired in course of the project by partner astronomer teams. Usually, to fit the numerical simulations to observations, different artificial assumptions are made either regarding the stellar radiation flux, which to significant extend is a measurable parameter constrained by the nature of the star, or about the specifics of interaction of the stellar and planetary material flows, as well as on the role of different physical effects to be included in the modelling. In contrast, the global fully self-consistent 3D multi-fluid model, developed in the project, which simulates the escaping atmosphere of hot close-orbit exoplanets and the surrounding stellar wind, is free of such assumptions. Were there changes in research orientation between the beginning and the end of the project? If so, what form did the change take, what effect did it have on the work?           The research plan initially described in the proposal has been extended towards more extensive simulation and interpretation of the newly obtained observational data (HST, WASP) regarding the transit absorption of different exoplanets and probing of their atmospheric composition as well as the structure of the escaping planetary wind flows. As a result, the modelling and visualization tools were developed to simulate and analyze the dynamics of major atmospheric elements and their ions, taking into account the whole range of plasma photo-chemistry reactions, particle collisions, and basic driving forces. The extended scope of studies included the simulation of mass loss and interpretation of the measured in-transit spectral absorption in various lines for the exoplanets HD 209458b (Lyα, OI, CII, SiI, MgI, MgII); WASP-12b (MgII); WASP-107b (HeI); π Men c (Lyα); GJ3470b (Lyα, HeI), and GJ436b (Lyα). Besides of that, the performed research revealed the limitations of the initially planned 2D model for the considered exoplanets. Their exospheres are extended over very large distances (> 10 planet radii), where the structure of the escaping planetary wind is affected by essentially 3D factors such as interaction with the stellar wind and the Coriolis force. Therefore the intended 2D modelling approach was upgraded to the global 3D simulations, which along with the aeronomy of the expanding upper atmospheres of exoplanets, included also the modelling of stellar winds. The real stellar radiation spectra (when available) were used in the modelling instead of the initially announced solar analog spectrum. As an additional direction, the methods for analysis of border regions of the transit light curves provided by the Kepler Space Telescope were developed, that enabled the probing of dusty structures possibly present the planetary and stellar material flows in the vicinity of some exoplanets. Most important results and brief description of their significance Contribution to the advancement of the field           The developed in project numerical modelling approaches, analysis methods, and obtained results open a new dimension in the simulation and interpretation of the phenomena of exoplanetary transmission photometry and spectroscopy. Based on the chemical code CHROME, the model of a multicomponent planetary atmosphere has been created, applicable to a wide range of exoplanets. It was integrated in the multi-fluid (M)HD models of the escaping exoplanetary upper atmospheres to enable the calculation of complete photo-chemistry reactions chain. The original 2D models were upgraded to the global 3D numerical code, which for the first time enabled a self-consistent simulation of the stellar winds and aeronomy of the expanding upper atmospheres of exoplanets in their mutual interaction. The actual version of the 3D multi-fluid model solves the equations of continuity, momentum, and energy for each atomic, molecular and ionized component. The main processes of particle interconversion are photoionization, electron impact, recombination, and charge exchange. Photoionization also leads to the heating of material by the generated photoelectrons. For each particular star, an appropriate XUV spectrum in the range of 10-912 Å is used. The transmission and attenuation of the XUV flux is calculated in each spectral interval in accordance with the wavelength-dependent absorption cross section. Besides of the radiative heating, the model includes also the cooling effect due to excitation of atomic hydrogen and infrared radiation of the H3+ molecule. The momentum exchange between various components occurs due to ion-atom and Coulomb collisions. The upper atmosphere of modelled giant exoplanets is taken to consist of H, H+, H2, H2+, H3+, He, and He+ components. In addition, the energetic neutral hydrogen atoms (ENAs), generated by charge-exchange between the planetary hydrogen and stellar wind protons, are considered as a separate component. At the same time, the model admits the inclusion of additional species, like, e.g., in the study of absorption by heavy minor species for HD 209458b (OI, CII, SiI, MgI, MgII) and WASP-12b (MgII). Besides of the escaping planetary atmosphere, the model also simulates (based on the same algorithms) the expanding stellar wind, enabling a self-consistent global view of the interacting planetary and stellar material flows (Fig.1). The code is implemented in a non-inertial spherical frame, centred at the planet and rotating in phase with its orbital motion. However, the planet itself can rotate with any period. The non-inertial forces are introduced via the generalized gravitational potential and the Coriolis force. The stellar radiation pressure force is also taken into account. The code’s solver is fully parallelized for performing on HPC. This model appears a cornerstone of the project goals, its major innovation and achievement. For the terrestrial type exoplanets the N2 and CO2 dominated atmospheres were modelled with the improved version of 1D Kompot Code, based on first-principles, taking into account the hydrodynamics and the main chemical and thermal processes in the upper atmosphere of a planet.                  Along with the elaboration of the global 3D multi-fluid model, a dedicated Python script was developed, based on the library provided by the Visualization Toolkit (VTK, https://www.vtk.org), that proprietary reads formats of the model. The script enables the creation of a 3D structured-grid-point file that can be imported into the Paraview (https://www.paraview.org - an application based on the VTK library), providing the volume rendering to visualize the 3D data (e.g. Fig.1). The script and its performance can be further customized using a number of (optional) parameters that are explained in detail in a ReadMe file available on Google Drive along with the script (https://drive.google.com/open?id=1CALA7JU4KecPPdMlgVMlLZZ740hEwJIo). The ReadMe file also explains the setup process as well as the visualization pipeline to use in Paraview in order to produce 3D visualizations.             Within the direction, dedicated to the analysis of the transit light curves, provided by the Kepler Space Telescope, to detect the photometric manifestations of possible optically opaque dusty structures in the streams of escaping planetary wind, a special technique was developed for analyzing the pre- and post-transit parts of the light curves. It is based on the calculation and statistic comparison of the flux gradients before and after the transit for the time intervals, which characterize different regions near the transiting object. New scientific/scholarly advances (1) Revealing of basic trends of the stellar and planetary winds interaction: The interaction of escaping upper atmosphere of a hydrogen rich non-magnetized hot Jupiter with the stellar wind of its host G-type star at different orbital distances was simulated using the self-consistent 2D multi-fluid hydrodynamic model and the realistic Sun-like spectrum of XUV. Two different regimes of the planetary and stellar winds interaction have been modelled. These regimes are: 1) the “captured by the star” regime, when the tidal force and pressure gradient drive the planetary material beyond the Roche lobe forming a two-stream structure of the flow with one stream directed towards the star and another outwards, and 2) the “blown by the wind” regime, when sufficiently strong stellar wind confines the escaping planetary atmosphere and channels it into the tail. It was shown that for the typical for solar-type stars, the escaping planetary wind of a typical hot Jupiter appears in the "captured by a star" regime. However, under an extreme stellar wind conditions with an order of magnitude higher ram pressure, or at sufficiently large orbital distances, leading to decrease of the tidal forces, the planetary wind turns to the "blown by the wind" regime. In this case, a shock wave is formed around the exoplanet within the Roche lobe. The detailed simulation of the structure and composition of multi-component planetary and stellar wind flows in the interaction region for both regimes was done for the first time (Published in Saikhislamov et al. 2016). (2) Modelling of the ENAs generation around exoplanets and Lyα absorption: For the first time, the cloud of ENAs formed by charge exchange between the planetary H atoms and stellar wind protons was simulated using the self-consistent multi-fluid hydrodynamic description, including all four components involved in the interaction: the planetary hydrogen, its ions, stellar protons, and ENAs. It was shown for the first time that the escaping planetary wind remains essentially collisional and strongly coupled up to distances of tens of planetary radii, due to the charge exchange reaction between the H atoms and ions and Coulomb collisions. The revealed location and shape of the ENA cloud in 3D, either as a paraboloid shell between ionopause and bowshock (for the “blown by the wind” regime), or as a turbulent layer at the contact boundary between the planetary stream and stellar wind (for the “captured by the star” regime) appeared of importance for the modelling and interpretation of Lyα absorption in exoplanetary transits (Published in Saikhislamov et al. 2016, Khodachenko et al. 2017). (3) Conclusion on the role of stellar radiation pressure in the acceleration of ENAs and HeI: It was shown for the first time, with the numerical modeling and analytical estimates, that Lyα radiation pressure, which was traditionally considered as the main mechanism for the production of ENAs, does not work for the typical hot exoplanets. The escaping planetary wind in fact remains dense even at long distances from the planet, and Lyα radiation does not penetrate deep into it, being absorbed in a thin transition layer. Therefore, the radiation force acts as just a surface pressure, similar to the ram pressure of the stellar wind, which is usually much higher. Besides of that, the planetary wind flow remains strongly coupled, with the momentum exchange between atoms and protons taking place (mainly due to the charge-exchange) at much smaller scales than the characteristic size of the system. This redistributes the radiation pressure force, acting on H atoms, over a much larger number of particles, and reduces its effect. Altogether, the main source of ENAs, and related significant absorption in the blue wing of Lyα, line is the charge-exchange reaction between the planetary H atoms and stellar wind protons (Published in Saikhislamov et al. 2016, 2020b, Khodachenko et al. 2017, 2019, Kislyakova et al. 2019). At the same time the stellar radiation pressure may appear crucial factor in the dynamics of other species in the planetary wind. In particular, it was shown in Khodachenko et al. (2021) that the radiation pressure acting on metastable HeI strongly affects the shape of the absorption profiles of WASP-107b. (4) Characterization of the dynamic plasmaspheres of exoplanets: For the first time, a self-consistent multi-component, global modelling of the energized by stellar radiation outflowing atmospheres of HD 209458b, WASP-12b, WASP-107b, π Men c, GJ3470b, GJ436b and the surrounding stellar winds was performed in 3D. The absorption in main resonance lines (Lyα, HeI, OI, CII, SiI, MgI, MgII) was simulated and fitted to observations (Hubble and WASP) enabling the probing of atmospheric composition, stellar radiation, and plasma environments (Published in Saikhislamov et al. 2018a,b, 2020a,b,c, Khodachenko et al. 2019, 2021, Dwivedi et al. 2019, Berezutsky et al. 2019). (5) Basic study of the stellar wind and planetary magnetic field effects: In continuation of the self-consistent 2D MHD modelling of the escaping planetary wind of a magnetized hot Jupiter, which in the case of a perpendicular to the orbital plane magnetic dipole of the planet revealed the formation of an equatorial magnetodisk (Khodachenko et al. ApJ 2015), the structure of the planetary wind flow was for the first time calculated for the case when the immersed in the stellar wind, planetary dipole is pointed towards the star. The current sheet of magnetodisk was also formed in this case, but it had the form of a cylinder surface extended along the planet-star axis. The surface of the current sheet was located near the magnetopause separating the stellar wind and planetary plasmas. Besides of that, using the 3D MHD model, the influence of magnetic field of the stellar wind on its interaction with the exosphere of a non-magnetized hot Jupiter and the generation of ENAs was investigated. A layer of an induced magnetic field of high intensity was found to form in the sub-Alfvénic stellar wind. It resulted in a significant displacement of the magnetosphere boundary towards the planet. Comparison of the model calculations with observations allowed estimating of the magnetic moment of HD 209458b at the level of 10–20% of the Solar System’s Jupiter value (Published in Erkaev et al. 2017). Further, the modelled magnetospheric plasma parameters and field topology were used to study the possibility of observing of the radio emission from hot Jupiters. It was found that the dense and strongly ionized exosphere around the planets significantly restricts the generation and propagation of the cyclotron radiation, as the plasma frequency is usually higher than the electron cyclotron frequency (Published in Weber et al. 2017a,b). (6) Escape and mass loss of the terrestrial type atmospheres: The transonic hydrodynamic escape of atmosphere was calculated for the first time for an Earth analog planet at 1AU orbit around a young active solar-mass star, using the Kompot Code. The escaping planetary wind dominated by atomic N and O, and their ions was shown to provide mass loss rates, which would erode the modern Earth’s atmosphere in less than 0.1 Myr. Such extreme mass loss suggests that an Earth-like atmosphere cannot form on the planet within the habitable zone (HZ) of an active star. Instead, such an atmosphere can only form after the activity of the star has decreased to a much lower level (Published in Johnstone et al. 2019). Besides of that, the Lyα transit signatures of a hypothetic Earth-sized planet placed in the HZ of the M dwarf GJ 436 were modelled and investigated for the cases of H- and N- dominated atmospheres, as well as for N-dominated atmosphere with an amount of H equal to that of the Earth. The multi-species Direct Simulation Monte Carlo (DSMC) code was used to simulate the planetary exosphere. The modelling revealed that only an Earth-like planet with H-dominated atmosphere can be detected in the HZ of GJ 436 by the present day Space Telescope Imaging Spectrograph on board of Hubble. Neither a pure nitrogen, nor the present Earth analog atmospheres are detectable (Published in Kislyakova et al. 2019). Additionally, the evolution of the polar ion outflow from the open magnetic field line bundle, which is the dominant escape mechanism for the modern Earth, was investigated using the DSMC simulations. The corresponding estimations of the upper limit on the escape rate for the Earth, starting from 3 Gyr ago to present, were made for different mixing ratios of oxygen. According to this study, the main factors that governed the polar outflow in the considered time period are the evolution of the solar XUV radiation and the atmosphere's composition. The evolution of the Earth's magnetic field plays a less important role (Published in Kislyakova et al. 2020). (7) Detection of dusty phenomena in the vicinity of giant exoplanets: Using linear approximation of pre- and post- transit parts of the light curves of 118 Kepler objects of interest (KOIs) after their preliminary whitening and phase-folding, the corresponding flux gradients G1 and G2, were calculated before and after the transit border for two different time intervals: (a) from 0.03 to 0.16 days and (b) from 0.01 to 0.05 days, which characterize the distant and adjoining regions near the transiting object, respectively. While in the distant region all flux gradients clustered around zero, revealing the absence of obscuring matter there, significantly negative gradients G1 were found in the adjoining region of 17 hot Jupiters, whereas G2 remained ~0. This effect was also reproduced with the models, using a stochastic obscuring precursor ahead the planet. The sporadic nature of the discovered phenomenon explains that it was not found earlier, and only the analysis of phase-folded transit light curves, prepared on the basis of the whole duration of observations, made its detection possible. Such phenomena may be caused by dusty atmospheric outflows, erosion and tidal decay of moonlets, or background circumstellar dust accumulated in electrostatic or magnetic traps in front of the mass-losing exoplanets (Published in Arkhypov et al. 2019). Additionally, the elaborated analysis method and the transit light curve modelling approaches were used to detect possible deviations of the shape of transiting exoplanetary shadows from the circular ones and to search in this way for the photometric manifestations of the non-spherical dusty obscuring structures near the planets (e.g., exorings). The key element of this methodology consists in using the derivatives of the transit light curve during the ingress and egress phases. Of 23 preselected candidate exoplanets, 7 objects were found to have peculiar non-circular shadows. Among them, Kepler-45b and Kepler-840b are the most intriguing, with the strongly elongated shadows (Published in Arkhypov et al. 2021). (8) Electric current dissipation effects in the partially ionized magnetized plasmas: As applied to hot exoplanets, namely HD 209458b, the presence of the planetary magnetic field and the escaping flow of the partially ionized upper atmospheric material should cause, due to Cowling conductivity, an additional dissipation of the transverse electric currents. At the same time, since the dissipated electric current is generated due to the motion of the escaping planetary wind across the magnetic field, and since the slip between protons and atoms is small, in particular because of the continuously going photo-ionization and charge exchange resulting in the strong coupling of the ionized and neutral components, the energy released due to Cowling dissipation accounts for only a small fraction of the kinetic and thermal energy of the planetary wind. However, this type of dissipation might be important in the localized regions of dynamically changing magnetic fields, e.g., at the points of the magnetodisk reconnection (Published in Ballester et al. 2018). Most important hypotheses / research questions developed (i) Revealing and characterizing of basic regimes of the stellar and planetary winds interaction; (ii) Conclusion on the role of the stellar radiation pressure in the acceleration of ENAs and HeI; (iii) Revealing of the 3D shape and location of the ENA cloud and production region; (iv) Explanation and simulation of the spectral lines’ absorption profiles and related mechanisms. Development of new methods (i) Global 3D multi-fluid self-consistent model of the interacting stellar and planetary winds; (ii) Simulation tool for the transmission spectroscopy phenomena on the basis of 3D (M)HD modelling; (iii) Visualization tool for the 3D simulated data. Added value of the international collaboration The implementation of the project was based solely on the cooperation of the Austrian and Russian teams. The Russian team was specializing on the development of (M)HD codes, performing calculations and analysis of the results, whereas the Austrian team provided its expertise in the physics of exoplanetary atmospheres and magnetospheres, atmospheric photo-chemistry, stellar winds, and analysis of observational data, taking the lead in selection of exoplanetary targets for the modelling and publishing of the project results in the high-ranking journals. Scientific formulation of the research tasks, interpretation of the simulation results, and preparation of the materials for publications, as well as their presentation at conferences, were done by both teams jointly. The whole project benefited from the availability of the powerful HPC resources on the side of the Russian partner, e.g., the Siberian Supercomputing Center (SSCC) and the Supercomputer of the Novosibirsk State University. Altogether, the joint project resulted in creation of the most advanced and complete numerical code for the global self-consistent modelling of escaping exoplanetary atmospheres interacting with the stellar winds, and the simulation of related transmission spectroscopy phenomena. Effects of the project in other areas of science and beyond the scientific field (A) The advanced global multi-fluid model developed in the project opens a way for the simulation of stellar weather processes in variety of stellar-planetary systems and to study the evolution of not only planetary objects, but also the astrosphere phenomena, like, e.g., stellar tori and secondary disks. The transmission spectroscopy simulator, integrated in the model, is of potential use for the search and analysis of possible biomarkers in exoplanetary systems. (B) The created 3D visualization tool can be used to analyse any 3D data.  (C) The elaborated methodology for the analysis of ingress and egress parts of the transit light curves enabled revealing and correction of the discrepancies in the definition of parameters of transiting exoplanets in the Kepler database, obtained with traditional methods. (D) Besides of the research work, the project participants took part in the RTD consortium the European H2020 project Europlanet-2020-RI. Publications   I.  Papers in peer-reviewed Journals:                     Khodachenko, M. L., Shaikhislamov, I. F., Fossati, L., Lammer, H., Rumenskikh, M.S., Berezutsky, A. G., Miroshnichenko, I. B., Efimof, M.A., Simulation of 10830 Å absorption with a 3D hydrodynamic model reveals the solar He abundance in upper atmosphere of WASP-107b, MNRAS: Letters, 2021, slab015 (DOI: https://doi.org/ 10.1093/mnrasl/slab015) Arkhypov, O.V., Khodachenko, M.L., Hanslmeier, A., Revealing of peculiar exoplanetary shadows from transit light-curves, Astron. & Astrophys., 2021, 646, A136 (DOI: https://doi.org/10.1051/0004-6361/202039050). Owen, J.E., Shaikhislamov, I.F., Lammer, H., Fossati, L., Khodachenko, M.L., Hydrogen Dominated Atmospheres on Terrestrial Mass Planets: Evidence, Origin and Evolution, Space Sci. Rev., 2020, 216, 129 (DOI: https://doi.org/10.1007/s11214-020-00756-w) Shaikhislamov, I. F., Fossati, L., Khodachenko, M. L., Lammer, H., García Muñoz, A., Youngblood, A., Dwivedi, N. K., Rumenskikh, M. S., Three-dimensional hydrodynamic simulations of the upper atmosphere of π Men c: comparison with Lyα transit observations, Astron. & Astrophys., 2020a, 639, A109 (https://doi.org/10.1051/0004-6361/202038363). Shaikhislamov, I.F., Khodachenko, M.L., Lammer, H., Berezutsky, A.G., Miroshnichenko, I.B., Rumenskikh, M.S., Three-dimensional modelling of absorption by various species for hot Jupiter HD 209458b, MNRAS, 2020b, 491, 3435–3447 (DOI: https://doi.org/10.1093/mnras/stz3211, Open Access) Shaikhislamov, I. F., Khodachenko, M. L., Lammer, H., Berezutsky, A. G., Miroshnichenko, I. B., Rumenskikh, M. S., Global 3D hydrodynamic modeling of absorption in Lyα and He 10830 Å lines at transits of GJ3470b. MNRAS, 2020c, 500(1), 1404-1413 (DOI: 10.1093/mnras/staa2367). Kislyakova, K. G., Johnstone, C. P., Scherf, M., Holmstroem, M., Alexeev, I. I., Lammer, H., Khodachenko, M. L., Guedel, M., Evolution of the Earth’s polar outflow from mid-Archean to present, JGR Space Phys., 2020, 125, e2020JA027837, (DOI: https://doi.org/10.1029/2020JA027837). Arkhypov, O.V., Khodachenko, M.L., Hanslmeier, A., Dusty phenomena in the vicinity of giant exoplanets, Astron. & Astrophys., 2019, 631, A152 (DOI: https://doi.org/10.1051/0004-6361/201936521) Khodachenko, M.L., Shaikhislamov, I.F., Lammer, H., Berezutsky, A.G., Miroshnichenko, I.B., Rumenskikh, M.S., Kislyakova, K.G., Dwivedi, N.K., Global 3D hydrodynamic modeling of in-transit Lyα absorption of GJ436b, ApJ, 2019, 885:67 (DOI: https://doi.org/10.3847/1538-4357/ab46a4, Open Access) Dwivedi, N. K., Khodachenko, M.L., Shaikhislamov, I. F., Fossati, L., Lammer, H. Sasunov, Y.L., Berezutskiy, A. G. Miroshnichenko, I. B., Kislyakova, K. G., Johnstone, C. P., Guedel, M., Modelling atmospheric escape and Mg II near-ultraviolet absorption of the highly irradiated hot Jupiter WASP-12b, MNRAS, 2019, 487, 4208–4220 (DOI: 10.1093/mnras/stz1345). Berezutsky, A. G., Shaikhislamov, I. F., Miroshnichenko, I. B., Rumenskikh, M. S., Khodachenko, M.L., Interaction of the Expanding Atmosphere with the Stellar Wind around Gliese 436b, Solar System Research, 2019, 53, No.2, p.138–145 (in Russian appeared in Astronomicheskii Vestnik, 2019, 53, p.147–154, ISSN 0038-0946) (DOI: 10.1134/S0038094619020011) Johnstone, C. P., Khodachenko, M.L., Lüftinger, T., Kislyakova, K. G., Lammer, H., Güdel, M., Extreme hydrodynamic losses of Earth-like atmospheres in the habitable zones of very active stars, Astron. & Astrophys., 2019, 624, L10 (DOI: https://doi.org/10.1051/0004-6361/201935279, Open Access). Kislyakova, K. G., Holmström, M., Odert, P., Lammer, H., Erkaev, N. V., Khodachenko, M. L., Shaikhislamov, I. F., Dorfi, E., Güdel, M., Transit Lyman-α signatures of terrestrial planets in the habitable zones of M dwarfs, Astron. & Astrophys., 2019, 623, id.A131 (DOI: 10.1051/0004-6361/201833941). Shaikhislamov, I.F., M.L. Khodachenko, H. Lammer, A. G. Berezutsky, I. B. Miroshnichenko, M. S. Rumenskikh, 3D Aeronomy modelling of close-in exoplanets, MNRAS, 2018a, 481, 5315–5323 (DOI: 10.1093/mnras/sty2652) Shaikhislamov, I. F., Khodachenko, M. L., Lammer, H., Fossati, L., Dwivedi, N., Güdel, M., Kislyakova, K.G., Johnstone, C.P., Berezutsky, A. G., Miroshnichenko, I. B., Posukh, V.G., Erkaev, N.V., Ivanov, V.A., Modeling of absorption by heavy minor species for the hot Jupiter HD 209458b, Astrophysical Journal, 2018b, 866:47 (DOI: https://doi.org/10.3847/1538-4357/aadf39 Open access). Ballester, J.L., Alexeev, I.I., Collados, M., Downes, T., Pfaff, R.F., Gilbert, H., Khodachenko, M.L., Khomenko, E., Shaikhislamov, I.F., Soler, R., Vázquez-Semadeni, E., Zaqarashvili, T., Partially Ionized Plasmas in Astrophysics, Space Sci. Rev. 2018, 214:58 (DOI: https://doi.org/10.1007/s11214-018-0485-6) Génot, V., Beigbeder, L., Popescu, D., Dufourg, N., Gangloff, M., Bouchemit, M., Caussarieu, S., Toniutti, J.-P., Durand, J., Modolo, R., André, N., Cecconi, B., Jacquey, C., Pitout, F., Rouillard, A., Pinto, R., Erard, S., Jourdane, N., Leclercq, L., Hess, S., Khodachenko, M.L., Al-Ubaidi, T., Scherf, M., Budnik, E., Science data visualization in planetary and heliospheric contexts with 3DView, Planetary and Space Science, 2018, 150, 111–130 (Open Access:  https://doi.org/10.1016/j.pss.2017.07.007) Khodachenko, M.L., Shaikhislamov, I.F., Lammer, H., Kislyakova, K.G., Fossati, L., Johnstone, C.P., Arkhypov, O.V., Berezutsky, A.G., Miroshnichenko, I.B., Posukh, V.G., Lyα Absorption at Transits of HD 209458b: A Comparative Study of Various Mechanisms Under Different Conditions, Astrophysical Journal, 2017, 847:126 (DOI: https://doi.org/10.3847/1538-4357/aa88ad) Weber, C., Lammer, H., Shaikhislamov, I. F., Chadney, J. M., Khodachenko, M. L., Grießmeier, J.-M., Rucker, H. O., Vocks, C., Macher, W., Odert, P., Kislyakova, K. G., How expanded ionospheres of Hot Jupiters can prevent escape of radio emission generated by the cyclotron maser instability, MNRAS, 2017a, 469, p.3505-3517 (DOI: 10.1093/mnras/stx1099). Erkaev N.V., Odert P., Lammer H., Kislyakova K.G., Fossati L., Mezentsev A.V., Johnstone C.P., Kubyshkina D.I., Shaikhislamov I.F., Khodachenko M.L., Effect of stellar wind induced magnetic fields on planetary obstacles of non-magnetized hot Jupiters, MNRAS, 2017, 470(4), 4330-4336 (DOI: 10.1093/mnras/stx1471) Shaikhislamov, I.F., Khodachenko, M.L., Lammer, H., Kislyakova, K.G., Fossati, L., Johnstone, C.P., Prokopov, P.A., Berezutsky, A.G., Zakharov, Yu.P., Posukh, V.G., Two regimes of interaction of a Hot Jupiter’s escaping atmosphere with the stellar wind and generation of energized atomic hydrogen corona, The Astrophysical Journal, 2016, 832, art.id. 173 (DOI: http://dx.doi.org/10.3847/0004-637X/832/2/173) Erkaev, N.V., Lammer, H., Odert, P., Kislyakova, K.G., Johnstone, C.P., Güdel, M., Khodachenko, M.L., EUV-driven mass-loss of protoplanetary cores with hydrogen-dominated atmospheres: the influences of ionization and orbital distance, Monthly Notices of the Royal Astronomical Society, 2016, 460, 1300-1309 (DOI:10.1093/mnras/stw935)    II. Papers in Proceedings of Conferences: Kislyakova, K., C. Johnstone, M. Scherf, M. Holmström, I. Alexeev, H. Lammer, M.L.Khodachenko, M. Güdel, Earth’s polar outflow evolution from mid-Archean to present, European Planetary Science Congress 2020, Göttingen, Sep 2020 (DOI: https://doi.org/10.5194/epsc2020-200). Shaikhislamov, I.F., Khodachenko M.L., Global 3D hydrodynamic modeling of GJ3470b and transit absorption in Lyα and He 10830 Å lines, European Planetary Science Congress 2020, Göttingen, Sep 2020 (DOI: https://doi.org/10.5194/epsc2020-147). Dwivedi, N.K., Khodachenko, M.L., Shaikhislamov, I.F., Berezutsky, A.G., Miroshnichenko, I.B., Fossati, L., Lammer, H., Sasunov, Y., Kislyakova, K.G., Johnstone, C.P., Güdel, M., 2020, A Hydrodynamic Modelling of Atmospheric Escape and Absorption Line of WASP-12b, in: IAU Symposium, p. 301–303 (DOI: 10.1017/S1743921319001480) Dwivedi, N.K., Khodachenko, M.L., Shaikhislamov, I.F., Al-Ubaidi, T., Fossati, L., Lammer, H., Berezutskiy, A.G., Miroshnichenko, I.B., Sasunov, Y., Güdel, M., A self-consistent three-dimensional aeronomy simulation of highly irradiated WASP-12b, EPSC-DPS Joint Meeting 2019, Genf, Sep 2019, p. EPSC-DPS2019-451. (https://meetingorganizer.copernicus.org/EPSC-DPS2019/EPSC-DPS2019-451-1.pdf). Khodachenko, M.L., O. Arkhypov, M. Güdel: Border variability of transit light-curves, EPSC-DPS Joint Meeting 2019, Genf, Sep 2019 (https://meetingorganizer.copernicus.org/EPSC-DPS2019/EPSC-DPS2019-119-1.pdf). Khodachenko, M.L., O. Arkhypov, M. Güdel: Dusty phenomena in vicinity of exoplanets, EPSC-DPS Joint Meeting 2019, Genf, Sep 2019 (https://meetingorganizer.copernicus.org/EPSC-DPS2019/EPSC-DPS2019-120-1.pdf). Khodachenko, M.L., O. Arkhypov, M. Güdel: Revealing of silhouette of an exoplanet from its transit light-curve, EPSC-DPS Joint Meeting 2019, Genf, Sep 2019 (https://meetingorganizer.copernicus.org/EPSC-DPS2019/EPSC-DPS2019-121-1.pdf). Shaikhislamov, I.F., Khodachenko, M.L., Berezutsky, A.G., Miroshnichenko, I.B., Rumenskikh, M.S., Dwivedi, N.K., Interpretation of transit observations of GJ436b by 3D gasdynamic modeling, EPSC-DPS Joint Meeting 2019, Genf, Sep 2019 (https://meetingorganizer.copernicus.org/EPSC-DPS2019/EPSC-DPS2019-72-1.pdf). Dwivedi, N., Shaikhislamov, I., Khodachenko, M.L., Fossati, L., Lammer, H., Kislyakova, K., Johnstone, C., Güdel, M., Sasunov, Y., 2018, Multi-fluid modeling of upper atmosphere mass loss and absorption line for WASP-12b, in: European Planetary Science Congress, p. EPSC2018-303 (https://meetingorganizer.copernicus.org/EPSC2018/EPSC2018-303.pdf). Khodachenko, M.L., Shaikhislamov, I., Dwivedi, N., Lammer, H., Kislyakova, K., Fossati, L., Johnstone, C., Arkhypov, O., Berezutsky, A., Miroshnichenko, I., Posukh, V., 2018, In-transit Ly-alpha absorption by HD 209458b under different regimes of the planetary and stellar winds interaction, in: European Planetary Science Congress, p. EPSC2018-281 (https://meetingorganizer.copernicus.org/EPSC2018/EPSC2018-281.pdf). Miroshnichenko, I.B., Shaikhislamov, I.F., Khodachenko, M.L., Lammer, H., Berezutsky, A.G., 2018, Modeling of the UV absorption by OI and CII in exosphere of the hot jupiter HD 209458b, in: European Planetary Science Congress, p. EPSC2018-158 (https://meetingorganizer.copernicus.org/EPSC2018/EPSC2018-158.pdf). Shaikhislamov, I.F., Khodachenko, M.L., Al-Ubaidi, T., Lammer, H., Berezutsky, A.G., Miroshnichenko, I.B., Rumenskikh, M.S., 2018, Global 3D multi-fluid aeronomy simulation of the HD 209458b, in: European Planetary Science Congress, p. EPSC2018-151 (https://meetingorganizer.copernicus.org/EPSC2018/EPSC2018-151.pdf). Weber, C., Lammer, H., Shaikhislamov, I., Chadney, J.-M., Erkaev, N., Khodachenko,M.L., Griessmeier, J.-M., Rucker, H.O., Vocks, C., Macher, W., Odert, P., Kislyakova, K.-G., On the Cyclotron Maser Instability in Magnetospheres of Hot Jupiters - Influence of ionosphere models, in: Planetary Radio Emissions VIII, Proceedings of the 8th International Workshop Held at Seggauberg, Austria, October 25-27, 2016, Edited by G. Fischer, G. Mann, M. Panchenko, and P. Zarka. Austrian Academy of Sciences Press, Vienna, 2017b, pp. 317-329. (DOI: 10.1553/PRE8s317)  
Wechselwirkung von entweichenden Atmosphären von close-orbit Exoplaneten mit Sternwinden  
Die Nähe vieler bekannter Exoplaneten zu ihren Wirtssternen führt zu einer intensiven Erwärmung und Ionisierung der oberen Atmosphäre durch Sternröntgen- und EUV-Strahlung. Infolgedessen dehnt sich das teilweise ionisierte Material der oberen Atmosphäre aus und bildet eine Art entweichenden Planetenwind. Auf größeren Höhenlagen interagiert diser Planetenwind, der durch die Druckkräfte der Gravitations-, Zentrifugal-, MHD- und Sternstrahlung angetrieben wird, und wird mit dem gesamten Sternwind entweder weggeblasen oder auf dem Stern angehäuft. Dies bildet die Essenz des planetaren Massenverlustes. Der entweichende Planetenwind, meistens ein Überschallwind, beeinflusst das gesamte Sternensystem und führt zu einer Vielzahl von bisher unerforschten Prozessen.                   In Übereinstimmung mit seinem Forschungsprogramm zielte das Projekt auf die Untersuchung und Charakterisierung verschiedener Regime exoplanetarer und stellarer Windwechselwirkungen ab, wobei deren Beobachtungsmanifestationen und die mögliche Rolle des planetaren Magnetfelds berücksichtigt wurden. Besonderes Augenmerk wurde auf die Simulation komplexer dynamischer Umgebungen von Exoplaneten und die Interpretation von realen Transmissions-Spektroskopie Daten gelegt, die im Rahmen des Projekts von Partnerteams aus Astronomen erfasst wurden.           Um die Projektziele zu erreichen, wurden mehrere numerische Codes entwickelt und aktualisiert. Basierend auf dem chemischen Code CHROME wurde das Modell einer Mehrkomponenten-Planetenatmosphäre erstellt, das auf eine Vielzahl von Exoplaneten anwendbar ist. Das Modell berechnet die chemischen Reaktionen in den ausgearbeiteten hydrodynamischen und MHD Modellen des austretenden exoplanetaren Materials der oberen Atmosphäre, welche  erweitert wurden, um die Dynamik vieler Elemente und ihrer Ionen (z. B. H, H2, H3, He, C, O, Mg, Si, N2, CO2) zu berechnen. Dabei werden alle Bereiche von Plasma-Photochemie-Reaktionen, Partikelkollisionen und grundlegenden Antriebskräften berücksichtigt. Die ersten 2D Modelle wurden im Verlauf des Projekts auf die globalen numerischen 3D Codes aktualisiert, die erstmals die selbstkonsistenten Simulationen der Sternwinde und der Aeronomie der expandierenden oberen Atmosphären von Exoplaneten in ihrer gegenseitigen Wechselwirkung ermöglichten. Die entwickelten Modelle wurden zur Simulation des Massenverlusts und zur Interpretation der in-transit spektralen Absorption benutzt. Gemessen wurden in verschiedenen Linien die Exoplaneten: HD 209458b (Lyα, OI, CII, SiI, MgI, MgII); WASP-12b (MgII); WASP-107b (HeI 10830 Å); π Men c (Lyα); GJ3470b (Lyα, HeI 10830 Å) und GJ436b (Lyα). Darüber hinaus, um die Atmosphärenentwicklung erdähnlicher Planeten in der Nähe aktiver Sterne zu untersuchen, wurden die hydrostatischen Mehrkomponentenmodelle von N2- und CO2-dominierten Atmosphären ausgearbeitet (1D Kompot Code). Als zusätzliche Richtung entwickelt das Projekt Methoden zur Analyse von Grenzbereichen der Transitlichtkurven, die vom Kepler-Weltraumteleskop bereitgestellt werden, und auf diese Weise zur Diagnose von staubigen Strukturen dienen, welche in unmittelbarer Nähe einiger Exoplaneten vorhanden sein können.  
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Magnetospheric electrodynamics of exoplanets Principal Investigator Dr. Maxim Khodachenko E-Mail maxim.khodachenko[at]oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 30.11.2015 Project duration Start: 01.03.2016   End: 30.04.2021 Scientific field(s) 103 (Physics, Astronomy): 100%  
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Magnetospheric electrodynamics of exoplanets Principal Investigator Dr. Maxim Khodachenko E-Mail maxim.khodachenko[at]oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 04.11.2011 Project duration Start: 01.03.2012   End: 29.02.2016 Scientific field(s) 103 (Physics, Astronomy): 100%  
Final Report  
Magnetospheric electrodynamics of exoplanets (I) Summary Investigation of key factors and physical mechanisms which determine the structure, topology and dynamics of exoplanetary magnetospheres at close orbits, formed the primary focus of the project. This topic is connected with the study of the whole complex of stellar-planetary interactions, as well as internal processes, including consideration of stellar radiation, plasma flows (e.g., stellar wind, coronal mass ejections), and radiative energy deposition at the upper atmospheric layers, as well as planetary and stellar winds interaction. Special attention was paid to the development of a set of modelling tools and approaches for the description and simulation of exoplanetary magnetospheres and their basic elements, taking into account the specifics of exoplanetary conditions at close to host star orbits, such as the expanding upper atmospheric material (escaping planetary wind) heated and ionized by the stellar XUV, and formation in some cases under the conditions of planetary intrinsic magnetic dipole field, of an equatorial current-carrying plasma disk (Khodachenko et al. 2012). The work within SP6 was based on the inputs regarding the stellar radiation and wind conditions from SP4, whereas the resulting exoplanetary magnetosphere estimations were used jointly with SP7 for the modelling of exoplanetary ENA coronas (Holmström et al. 2008, Ekenbäck et al. 2010) and related diagnostics of stellar winds and planetary magnetic fields (Kislyakova et al. 2014a). The approach of the first four years of the project, consisted in simultaneous research in two basic directions: 1) the investigation of inner structure and large-scale features of the exoplanetary magnetospheres, taking into account the effects of expanding and escaping planetary upper atmospheric material, and interaction of such magnetospheres with the stellar winds; 2) the development of deep insight into fine structure and fundamental physics of the global magnetospheric current systems, e.g., thin current sheets of magnetodisk and magnetotail, with the methods of plasma kinetic theory. Besides of that, the experimental (laboratory) simulation of magnetodisk formation during the plasma outflow from the region with the central magnetic dipole was performed (Antonov et al. 2013). The facility used for this study was the vacuum chamber KI-1 at the Institute of Laser Physics of the Russian Academy of Sciences. The typical disk-type distribution of the electric current magnetic field and plasma dynamics were measured in the experiment. Altogether the experimental results confirmed the theoretical and numerical modelling predictions regarding the inner structure and topology of exoplanetary magnetosphere under the conditions of escaping planetary plasma wind. All the obtained results were published in refereed scientific media and reported on specialized national and international meetings.  Scientific Background / State of the art The constantly growing number of discovered exoplanets and accumulation of data regarding their physical and orbital characteristics provide an empirical platform for a more detailed study of general principles and major trends of the formation and evolution of planets and planetary systems (including the potential habitability aspect). More than a half of known exoplanets have orbits around their host stars shorter than 0.6 AU. By this, an evident maximum in the orbital distribution of exoplanets takes place in the vicinity of 0.05 AU, with two well pronounced major populations there, corresponding to the giant type planets (0,2MJ < Mp < 8MJ ), so called Hot Jupiters (HJs), which comprise about 30% of the total number of known exoplanets, and less massive (0,008MJ < Mp < 0,08MJ ) Neptune- and Earth- type planets. Here MJ stays for the mass of Jupiter. The fact of presence of exoplanets (especially HJs) at close orbital distances opens questions regarding their mass loss, evolution, and related to that, upper atmosphere structure, its interaction with extreme stellar wind plasma flows (Yelle 2004, Holmström et al. 2008, Ekenbäck et al. 2010) and stability against escape of atmospheric gas (e.g., Guillot et al. 1996). The stellar X-ray/EUV (XUV) radiation energy deposition results in heating ionization and consequent expansion of the planetary atmosphere which contributes to the so-called atmosphere thermal escape and related mass loss (Lammer et al. 2003, 2013, Yelle 2004, García Muñoz 2007, Guo 2011, 2013, Koskinen et al. 2010, 2013). Above the exobase and the magnetopause (if it exists), i.e. in the regions of direct interaction of the expanding atmosphere with the stellar wind, the escaping particles are picked up by the stellar wind plasma flow resulting in a non-thermal mass loss. The planetary magnetic field appears a crucial factor which influences both, thermal and non-thermal types of the mass loss of close-orbit exoplanets. In general, this influence has two major aspects. First, the related with the planetary magnetism, large-scale magnetic field and electric currents, form in the surrounding space plasma the planetary magnetosphere which acts as a barrier for the upcoming stellar wind and protects the ionosphere and upper atmosphere of a planet against direct impact of stellar plasmas and energetic particles, which constitute the major factors of the non-thermal mass loss (Khodachenko et al. 2007a, Khodachenko et al. 2007b). Second, the internal magnetic field of the planetary magnetosphere strongly affects the thermal mass loss by influencing the outflow of the expanding planetary plasma and its further interaction with the stellar wind (Adams 2011, Trammell et al. 2011, 2014, Owen and Adams 2014, Khodachenko et al. 2015). Therefore, the processes of material escape and planetary magnetosphere formation have to be considered jointly in a self-consistent way in their mutual relation and influence. The expanding planetary wind interacts with intrinsic magnetic dipole field and appears a strong driver in formation of exoplanetary magnetosphere, which in its turn influences the overall mass loss of a planet. For the efficient magnetospheric protection of a planet, the size of magnetosphere should be sufficiently large to prevent direct erosion of the atmosphere by stellar wind (Grießmeier et al. 2004). However, early the estimates showed that an intrinsic magnetic dipole moment of a tidally locked close-orbit exoplanet is very likely too weak to build alone a sufficiently large magnetosphere which could protect the planetary upper atmosphere against erosion by the stellar wind (Khodachenko et al. 2007b). To explain the survival of HJs in extreme conditions near their host stars, Khodachenko et al. (2012) proposed a more generic view of an exoplanetary magnetosphere which takes into account the expanding upper atmospheric gas heated and ionized by the stellar XUV radiation. The interaction of outflowing partially ionized planetary plasma wind with the rotating planetary magnetic dipole field leads to the development of a current-carrying magnetodisk. By this, two major regions with different topology of the magnetic field (Mestel, 1968, Trammell et al. 2011) can be distinguished in the magnetosphere driven by the escaping plasma flow. In the so-called “dead-zone” the magnetic force is strong enough to lock plasma with the planet and to keep the field lines closed. In the “wind-zone” the expanding plasma drags and opens the magnetic field lines, leading to appearance of a thin current-carrying magnetodisk. The field of magnetodisk under typical conditions of a close-orbit HJ’s, by far exceeds the dipole field. Altogether, this leads to the development of a new type of magnetodisk-dominated magnetosphere (Khodachenko et al., 2012). Such expanded magnetospheres of HJs have been shown to be up to 40-70% larger, as compared to the traditionally estimated dipole-type ones (Griemeier et al., 2004; Khodachenko et al., 2007a,b). That enabled to resolve a problem of better magnetospheric protection of close-orbit HJs against of the non-thermal erosive action of the stellar winds (Khodachenko et al., 2012). Note, that the specifics and even existence of magnetodisks by lower mass exoplanets (e.g., Neptune- or Terrestrial type), under different stellar wind and radiation conditions, is still a subject for further investigation. Two basic processes, acting simultaneously, are responsible for the formation of exoplanetary magnetodisk and related structuring of the whole magnetosphere: 1) thermal expansion of the escaping planetary plasma wind, heated by the stellar radiation, and 2) centrifugal acceleration of plasma by rotating planetary magnetic field in the co-rotation region, with subsequent release of material in the vicinity of a centrifugal Alfvénic surface (a so-called “sling” mechanism) (Alekseev et al. 1982, Khodachenko et al., 2012). A simultaneous self-consistent description of both mechanisms represents an important and complex physical problem, and so far these processes are treated separately. That is possible in the case of close-orbit tidally locked planets which are subject to strong radiative energy deposition whereas rotational effects are usually much weaker, as the planetary rotation is synchronized with the orbital revolution (Antonov et al. 2013, Shaikhislamov et al. 2014). In this case, the radial expansion of the hot planetary plasma dominates the corotation in the inner magnetosphere. Besides of a qualitative as well as numerical treatment of the inner (dipole-dominated) and outer (magnetodisk-dominated) parts of an exoplanetary magnetosphere (Adams 2011, Trammell et al. 2011, 2014, Khodachenko et al. 2012, 2015,  Shaikhislamov et al. 2014), the formation of magnetodisk by plasma outflow in a dipole field was demonstrated in laboratory experiment (Antonov et al. 2013). The development of a self-consistent model of an exoplanetary magnetosphere which properly includes all the basic physical effects and conditions still remains a challenging task. Self-consistent treatment based on 2D MHD codes has been recently performed by (Trammell et al. 2014, Owen and Adams 2014) in which “dead-” and “wind-zones” have been shown to form in the expanding planetary wind. However, the thermosphere heating and the hydrodynamic flow initiated close to the planetary surface were simulated with rather simplified models, assuming a mono-energetic XUV flux, homogenous (e.g., Trammell et al. 2014), or empirically estimated gas temperature, and variable boundary conditions at the planet surface. Note, that the last are known to influence the expanding planetary wind solution (Adams 2011, Trammell et al. 2011, Shaikhislamov et al. 2014). As a result, the obtained estimations for the magnetic field, at which the planetary wind of HD209458b is significantly suppressed, vary in different papers by more than an order of magnitude. Moreover, despite of the recognition of importance of the “dead-” and “wind-zones” in the context of the planetary magnetosphere topology and related atmospheric mass loss, another important structure – magnetodisk – which is closely associated with these regions and influences the global size of the magnetosphere (Khodachenko et al. 2012), has not been sufficiently modelled and investigated so far. A special group of unsolved questions relates the macro- and micro- scaling of exoplanetary magnetospheric current systems, including those of the magnetodisk, magnetotail and magneopause regions. Their global configuration and topology depend significantly on the conditions of incoming stellar wind (Grießmeier et al. 2004, Khodachenko et al. 2012), whereas the internal scaling and fine structure are defined by the specifics of particle kinetics in self-consistent field of a current sheet. Their detailed study requires a separate treatment with development of special methods and approaches (Alexeev and Malova 1990, Zelenyi et al. 2011, Sasunov et al., 2015a,b,c), which go beyond the traditional MHD used for the description of escaping magnetized planetary winds. Results and Discussion The work during the first four project years (PYs) was performed in line with the proposed research plan. It comprised simultaneous research in two basic directions: First, the investigation of inner structure and large-scale features of the exoplanetary magnetospheres, taking into account the effects of expanding and escaping planetary upper atmospheric material heated by stellar radiation, and interaction of such magnetospheres with the stellar winds; Second, the development of deep insight into fine structure and fundamental physics of the global magnetospheric current systems, e.g., thin current sheets of magnetodisk and magnetotail, mainly with the methods of plasma kinetic theory. Within the scope of the first direction, the primary goal was to gain better understanding of the physics of the exoplanetary magnetodisk formation. At the time of the project begin, only a simplified semi-qualitative treatment of the case (Kodachenko et al. 2012) has been done, and the whole idea of the disk appearance around a close-orbit giant planet needed its check. In that respect, assuming a close-orbit tidally locked slowly rotating exoplanet with the dominating thermal expansion mechanism of the escaping planetary wind (as compared to the centrifugal one) (Antonov et al. 2013, Shaikhislamov et al. 2014) two research approaches were undertaken during the PY1. (A) To consider a pure case of interaction between the planetary magnetic dipole field and outflowing plasma, a numerical MHD modelling of a simple case of the expanding isothermal plasma in the presence of the background dipole field, without inclusion of planetary and stellar effects (e.g., gravity, radiation, stellar wind, atmospheric composition, etc.) has been performed. (B) Along with MHD modelling, also the experimental (laboratory) simulation of magnetodisk formation during the plasma outflow from the region occupied by the magnetic dipole field was done (Antonov et al. 2013). The experimental facility used for this study was the vacuum chamber KI-1 at the Institute of Laser Physics of the Russian Academy of Sciences. Both, experimental and simple MHD simulations confirmed the theoretically expected (Mestel 1968, Alexeev 1982, Kodachenko et al. 2012) specific distortion of the dipole field topology by the expanding plasma with the appearance of a thin equatorial current-carrying disk, which begins beyond the Alfvénic distance (where the flow becomes super-Alfvénic). However, the obtained results of the experimental and numerical modelling, due to some oversimplifications imposed, which ignore several crucial effects, in spite of giving a general picture of the exoplanetary magnetosphere structure, could not be directly applied for the quantitative characterization of real exoplanets. To make a step forward on that way, SP6 developed in the PYs 2 and 3 an advanced numerical model which simulates in a self-consistent way the processes of XUV heating, ionization and expansion of the exoplanetary upper atmosphere including the consequent interaction of the escaping planetary plasma  wind with the magnetic field of planetary dipole. The primary goal of this modelling work, besides of the revealing the details of exoplanetary magnetosphere structure, was to simulate and to quantify the process of thermal mass loss of a close-orbit exoplanet and to conclude about the role of planetary intrinsic magnetic field in that respect. The investigation of exoplanetary magnetospheres by means of numerical simulations requires an efficient and well organized model capable to support a comparative study of different physical effects and processes which contribute to the formation and shaping of the magnetosphere. To investigate all the relevant physical effects and the role of planetary intrinsic magnetic field in the process of atmospheric material escape and mass loss, as well as formation and structuring of planetary inner magnetosphere in a self-consistent way, we adopt a two-step modeling strategy, starting (as a first step) with a hydrodynamic (HD) model of atmosphere expansion driven by the stellar XUV (Shaikhislamov et al. 2014). After having developed a comprehensive model for an expanding upper atmosphere of an exoplanet, we performed, as a next step, the magnetohydrodynamic (MHD) modeling (Khodachenko et al. 2015), with the inclusion of planetary intrinsic magnetic dipole field and studied its role in formation of the inner magnetosphere and atmospheric thermal mass loss. Therefore, in PY2 we started with a 1D non-isothermal HD model of an upper atmosphere expansion driven by the stellar XUV (Shaikhislamov et al. 2014). While considering a simple hydrogen atmosphere model of a close-orbit HJ, we focused on self-consistent inclusion of the effects of radiative heating and ionization of the atmospheric gas with its consequent expansion in the outer space. Primary attention was paid to investigation of the role of specific conditions at the inner and outer boundaries of the simulation domain, under which different regimes of material escape (free- and restricted- flow) are formed. Comparative study of different processes, such as XUV heating, material ionization and recombination,  cooling, adiabatic and Lyman-alpha cooling, Lyman-alpha reabsorption was performed. The basic consistence of the outcomes of our HD modeling with the results of other similar models of expanding planetary atmospheres was confirmed (see Fig.4.5.1). We obtained that under the typical conditions of an orbital distance 0.05 AU around a Sun-type star a HJ’s plasma envelope may reach maximum temperatures up to ~9000K with a hydrodynamic escape speed ~ 9 km/s resulting in the mass loss rates ~  . In the range of considered stellar-planetary parameters and XUV fluxes that is close to mass loss in the energy limited case. During the PYs 2 and 3 our “first-step” 1D HD model (Shaikhislamov et al. 2014) was further improved and extended to the 2D geometry case, which is needed (at least) for MHD simulation of the magnetized planetary wind (Khodachenko et al. 2015). Besides of the geometry, the model improvement comprised the inclusion of a realistic solar-type XUV spectrum for calculation of intensity and column density distribution of radiative energy input, account of the one-side illumination of a planet by its host star, incorporation of basic hydrogen chemistry for the appropriate calculation of major gas species in HJ’s upper atmosphere and related radiative energy deposition, as well as H3+ and Lyα cooling processes. The improved model also takes into account gravitational and rotational forces acting in a tidally locked planet-star system. As a next step, in-line with the adopted two-step model development approach, the improved 2D HD model of the HJ’s expanding hydrogen atmosphere was generalized in the PY3 to include the effects of intrinsic planetary magnetic field (Khodachenko et al. 2015). This axisymmetric 2D MHD model, which due to self-consistent inclusion of the major effects and processes, appears the most advanced model of that kind nowadays, was used to demonstrate that the interaction between the expanding atmospheric plasma and the intrinsic planetary magnetic dipole field leads to the formation of a current-carrying magnetodisk and the specific regions inside the magnetosphere, e.g., “dead-zone” and “wind-zone” (Fig.4.5.2a) which all play an important role for topology and scaling of the whole exoplanetary magnetosphere. As an essentially new feature, a cyclic character of the magnetodisk behaviour, comprised of consequent phases of the disk formation and following magnetic reconnection with ejection of a ring-type plasmoid has been discovered and investigated. It has been found that the mass loss rate of an analog of HD209458b planet is only slightly affected by equatorial surface field of 0.3 G, but is suppressed by order of magnitude at a field of 1 G with the consequent decrease for higher surface field values (Fig.4.5.2b). The advanced 2D MHD model enabled for the first time the detailed investigation of fine structure, as well as plasma dynamics and force balance in the “dead-“ and “wind-zone”, which appear of special importance as a source of potentially observable effects and phenomena. Another set of investigations within the first research direction of the SP6 concerned the characterization of planetary global magnetospheric obstacle under different planetary and stellar wind conditions. This in particular includes the study of paleo-terrestrial magnetosphere with the generalized paraboloid magnetosphere model (PMM) elaborated in Khodachenko et al. (2012) under different conditions of the young solar wind, taking into account the recently reported paleo-geological data regarding terrestrial magnetism, which estimate the terrestrial magnetic field as ~50 to 70% that of the present-day field (Tarduno et al. 2010). The goal of this investigation which will be performed during the PY4 jointly with SP4 and SP7, is to conclude about the role of paleo-terrestrial magnetosphere in the long-term evolution of the terrestrial atmosphere and formation of its present-day conditions. Besides of that, since the end of the PY3 (according to proposed plan) the development of a combined PMM and hybrid HYB model for the describtion of planetary magnetosphere interaction with a stellar wind has been started. As a test object for the development of such a synthetic model and a prototype of a moderately close-orbit exoplanet, the solar system planet Mercury has been taken. The preliminary result of the synthetic model run (low resolution) is shown in Fig. 4.5.3. The new model appears a unique tool for the investigation of planetary magnetosphere large-scale shaping which combines the advantages of its basic components, PMM and hybrid modelling platform HYB. Within the scope of the second research direction, the scaling of inner edges of different types of astrophysical disks, including exoplanetary magnetodisks, was studied during the PY1 with a purpose to detect their common features caused by magnetic field of the disk hosting object (Belenkaya & Khodachenko 2012). After that, during PY2, the motion of particles in the region of a symmetric thin current sheet (TCS) has been investigated within a cold plasma assumption, i.e. neglecting the effects of the velocity thermal dispersion. The analytical solutions for the electric current density and plasma parameters in the TCS were obtained. Further on, in PY3, the analysis of particle motion has been extended to the case of a non-monochromatic particle population (Sasunov et al. 2015a). Based on the analysis of particle trajectories, the distributions of the electric current density and plasma parameters in the TCS were calculated analytically and numerically. A set of theoretical approaches for the self-consistent description of a TCS and surrounding plasma has been suggested.  A crucial point here is that the initial current and magnetic field configuration are created by a special population of electrons or suprathermal ions, whereas the majority of partcles then are self-consistently distributed to support the initial configuration. The analysis of amplitude of the current and particle number density in a TCS for different distribution functions of pitch-angle enabled estimation of its characteristic scale, as a function of particle pitch angle. It was shown that the structure of the current sheet depends strongly on pitch-angle distribution function and is determined by two competing currents: diamagnetic and paramagnetic ones. The obtained analytic expression for the TCS scaling has been shown to agree in the limiting cases with known estimates derived under more general assumptions. The comparison of scaling of the observed natural current sheets and the results of analytical calculation was made in Sasunov et al. (2015b). Along with that, as a proxy of reconnection processes in exoplanetary magnetospheres and stellar winds, a detailed analysis of reconnection layers in the solar wind has been performed. The process of reconnection was studied by solving Riemann problem. To compare the obtained analytical solutions with real data, 51 cases of reconnection in solar wind (satellite Wind 1995 - 2005) were analyzed. The results show good qualitative and quantitative agreement (Sasunov et al. 2015c). 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Final Report  
Magnetospheric electrodynamics of exoplanets (II) Summary Investigation of key factors and physical mechanisms which determine the structure, topology and dynamics of exoplanetary magnetospheres and their role in the evolution of planetary atmospheric environments and habitability, formed the focus of project. This goal is connected with the study of the whole complex of stellar-planetary interactions, as well as additional factors, e.g. stellar radiation and wind, circumplanetary dust, planetary magnetic field, considered over the planet history time scales. Special attention was paid to development of theoretical approaches and modelling tools for simulation of exoplanetary magnetized environments and understanding of their observational manifestation. The work in SP06 comprised simultaneous research in two basic directions. First direction includes the investigation of structure and large-scale features of exoplanetary magnetospheres, taking into account the effects of escaping planetary upper atmospheric material and its interaction with the stellar winds. This work involved application of the paraboloid magnetosphere model (PMM) of an exoplanet (Khodachenko et al. 2012) complimented with a dedicated study of upper atmosphere aeronomy related with the expansion and mass loss. The latter was based on hydrodynamic and magnetohydrodynamic (HD/MHD) models of the expanding exoplanetary atmospheres in the presence planetary magnetic field and stellar wind flow. Second direction deals with development of deep insight into physics and fine structure of the magnetospheric current system, e.g., thin current sheets of magnetodisk and magnetotail, using the methods of plasma kinetic theory. This required elaboration of special approaches (Sasunov et al., 2015a,b,c), which go beyond the traditional MHD used for the description of escaping magnetized planetary winds. As result, a way for analytic self-consistent description of charged particles motion in key regions of exoplanetary magnetosphere current systems has been elaborated (Sasunov et al. 2015b, 2017, 2018). Regarding possible observational manifestations of the dynamical processes in exoplanetary magnetospheres and near-by plasma environments, the transit spectral absorption features (e.g., Khodachenko et al. 2017) and the efficiency of the electron cyclotron maser instability (ECMI) mechanism of radio emission, as well as the conditions for its escape, were investigated (Weber et al. 2017). The need to quantify the stellar XUV impact on exoplanetary environments lead to development of a proxy approach for the stellar X-ray/EUV luminosity (Arkhypov et al. 2018), whereas complex dynamical multicomponent media around exoplanets and especially the circumplanetary dust contaminations were probed by the analysis of anomalous features and asymmetries in the optical transit light-curves. This project work was done jointly with other NFN subprojects (e.g., SP04, SP07) and collaborating FWF projects (P25587-N27, I2939-N27). Scientific background and aims of research The close location of giant exoplanets, so-called hot Jupiters (HJs), to host stars leads to intensive heating and ionization of their upper atmospheres by the stellar X-ray/EUV (XUV) radiation, resulting sometimes in hydrodynamic (HD) escape of the ionized atmospheric material in the form of expanding planetary wind (PW), which contributes to the so-called thermal mass loss of the planetary atmosphere. In the region of interaction of the expanding PW with the stellar wind (SW) the escaping particles are picked up by the SW, resulting in a non-thermal mass loss. In fact, both kinds of the mass loss operate together and have to be treated simultaneously in a unified manner, taking into account the self-consistent generation of the escaping PW and its interaction with the incoming SW, including the effects of the planetary and stellar magnetic fields and gravitational force. This constitutes the global problem, which was tacked within SP06. The expanded atmospheres and escaping PW have been studied by means of HD models in Yelle (2004), Tian et al. (2005), García Muñoz (2007), Erkaev et al. (2005, 2007), Murray-Clay et al. (2009), Guo (2011, 2013), and Koskinen et al. (2010, 2013).. The work of SP06 in that respect was aimed at development of a set of fully self-consistent 1D, 2D and 3D multi-fluid HD models, which include the hydrogen and helium plasma photo-chemistry, self-consistent XUV radiation energy input to the upper atmosphere of planets, effects of gravity, and the SW plasma flow. The present day extensive study of the Solar system planetary magnetospheres provides important background for investigation of exoplanetary magnetospheres. However, the ‘solar’-‘extrasolar’ analogy still remains very limited and must be applied with caution. The influence of magnetic field has two major aspects. First, the large-scale fields and related electric currents form the planetary magnetosphere which acts as a barrier for SW and protects the ionosphere and upper atmosphere of planet against direct impact of SW plasma (Khodachenko et al. 2007a,b; Khodachenko et al. 2012). Second, the magnetic field in inner part of planetary magnetosphere affects the expanding PW plasma and its further interaction with SW, being at the same time influenced by the moving plasma (Trammell et al. 2011; Owen and Adams 2014; Khodachenko et al. 2015). Detailed investigation of these processes in the context of escaping planetary atmospheres and mass loss was among the strategic goals, aimed in SP06. Particular attention was paid to evaluation of the role of the magnetosphere scaling and the equatorial magnetodisk, as well as the associated “dead-“ / “wind-“ zones (Mestel 1968; Trammel et al. 2014; Owen and Adams 2014; Khodachenko et al. 2015) in the planetary mass loss. The treatment of magnetic field effects in the context of interacting PW and SW requires development of a global self-consistent multi-fluid 3D MHD model of the stellar-planetary system, hitherto not existing. The work performed in SP06 (jointly with FWF project I2939-N27) on development of such kind 3D HD model (Shaikhislamov et al. 2018a), as well as the combined modelling approach based on 3D hybrid and PMM numerical concepts (Parunakian et al. 2017; Alexeev et al. 2018), together with the 2D MHD model by Khodachenko et al. (2015) appear a crucial step on this way. The development of a consistent approach to the description and modelling of exoplanetary magnetospheres with inclusion of an appropriate physics requires an account of multi-scale specifics of the problem. HD/MHD models give only a global large-scale picture of the stellar-planetary interaction and roughly indicate the location and topology of major elements of the planetary magnetospheric current system (e.g., magnetotail, magnetopause, magnetodisk), not being able to resolve their real fine structure. The kinetic effects of magnetized charged particles motion appear of crucial importance for the structuring, scaling and energetics of these fundamental magnetospheric components. The particular goal of SP06 in that respect was to understand the macro- and micro- scalings in exoplanetary magnetospheres in their mutual relation. The research scope included comparative study of the magnetosphere sizes (macro-scale) under different stellar activity and SW conditions, to conclude on magnetospheric protection and possible evolution scenarios for the terrestrial planets’ atmospheres, as a crucial factor of planetary habitability. This approach was applied to ancient Terrestrial and Martian magnetospheres under the conditions of young Sun to shed light on the atmospheres’ evolutional pathways. Complimentary to that, a novel approach, based on the analysis of charged particles trajectories in the self-consistent magnetic field (Sasunov et al. 2015a,b, 2017, 2018) has been elaborated in SP06, to investigate physical backgrounds and fine structure (micro-scale) of current sheets of exopanetary magnetotails, and magnetodisks, confirmed with laboratory experiments and MHD models (Antonov et al. 2013; Khodachenko et al. 2015). Another challenge concerns a possibility of observational characterization of exoplanetary magnetospheric phenomena. In that respect the task for scientists consists in further identification and investigation of the potential observables, among which planetary radio emission (e.g., Zarka 2007) and in-transit spectral absorption (e.g., Linsky et al. 2010; Vidal-Madjar et al. 2013) are considered. SP06, jointly with SP04, SP07 and the partner FWF project I2939-N27, studied the efficiency of ECMI mechanism of radio emission on HJs and the conditions for the radiation escape (Weber et al. 2017). Another direction was the model-based characterization the in-transit spectral absorption (Kislyakova et al. 2014; Khodachenko et al. 2017; Shaikhislamov et al. 2018b; Dwivedi et al., 2019) Results and discussion of results The work in SP06 went in two basic directions: First, investigation and modelling of the dynamics and large-scale structuring of exoplanetary near-by multicomponent plasma environments taking account of magnetic field effects, stellar radiation and SW; Second, the development of deep insight in fine structure and electrodynamics of the magnetospheric current system elements. In both cases, special attention was paid to identifying and characterization of the potentially observable phenomena. Within the scope of first direction, primary goal was to gain better understanding of the large-scale structure of close-orbit exoplanetary magnetospheres affected by the expanding PWs. Magnetodisk-dominated magnetospheres of HJs and their macro-scaling. A more complete view of magnetosphere of a close-orbit giant exoplanet, based on the Paraboloid Magnetospheric Model (PMM), was proposed (Khodachenko et al. 2012). Besides of intrinsic planetary magnetic dipole, PMM includes the electric current systems of magnetotail, magnetopause, and wagnetodisk. The key novel element of the considered model consists in the account of effects of HJ’s expanding upper atmosphere heated by stellar XUV radiation. The escaping atmospheric material is ionized and builds an extended magnetodisk around the planet which determines the magnetosphere size. A slower, than dipole-type decrease of the magnetic field with distance constitutes an essential specifics of the magnetodisk-dominated magnetospheres of HJs, which are 40 - 70 % larger, as compared to the traditionally considered dipole-type magnetospheres. Such larger magnetospheres provide better protection of close-orbit planets against extreme SWs. Additionally, the scaling of inner edges of different types of astrophysical disks, incl. exoplanetary magnetodisks, was studied to conclude on their common features caused by magnetic field of disk hosting object (Belenkaya & Khodachenko 2012, Belenkaya et al. 2012, 2015). Laboratory simulations of HJ’s magnetodisk formation. To verify the idea of an inflated magnetodisk-dominated magnetosphere of HJ, formed under conditions of an expanding PW in the background planetary dipole magnetic field, a dedicated laboratory experiment has been performed (Antonov et al. 2013). The vacuum chamber KI-1 at the collaborating partner Institute of Laser Physics of the Russian Academy of Sciences was used for this study. The measured magnetic field, electric current, and plasma density (Fig.SP06-1) indicate formation of a thin current disk extending beyond the Alfvénic point. At the edge of disk, the induced magnetic field was found to be several times larger than the field of dipole source. This experiment confirms the theoretically expected (Mestel 1968, Kodachenko et al. 2012) specific distortion of the dipole field topology in the magnetosphere of HJ under the conditions of expanding PW. Self-consistent HD/MHD modelling of the HJs’ PW and plasma environments. A series of numerical self-consistent models has been developed in SP06 to simulate the processes of XUV heating, ionization and expansion of exoplanetary upper atmospheres including the consequent interaction of escaping PW with the magnetic field of planetary dipole and SW. Besides of revealing of details of exoplanetary magnetosphere structure, the goal was to simulate the dynamics of complex multicomponent environments of close-orbit exoplanets and their mass loss. To investigate the role of different physical effects and conditions, potentially affecting the process of atmospheric escape, formation of inner magnetosphere, and mass loss, SP06 started with 1D HD multi-fluid model of an expanding upper atmosphere (Shaikhislamov et al. 2014). The focus was on self-consistent inclusion of the XUV radiative heating and ionization of the atmospheric gas with its consequent escape in the outer space with the inclusion of H3+ cooling, adiabatic and Lyα cooling, Lyα reabsorption and radiation pressure effects. As a next step, the HD model of expanding exoplanetary atmosphere was generalized to the case of a magnetized planet, to study the topology of inner magnetosphere, escaping PW, and mass loss. This self-consistent axisymmetric 2D MHD model, besides of the above mentioned features of 1D model, includes the basic hydrogen chemistry, realistic solar-type XUV spectrum, as well as the gravitational and rotational forces acting in the tidally locked planet-star systems (Khodachenko et al. 2015). The formation of a current-carrying magnetodisk and its cyclic behavior were discovered and investigated (Fig. SP06-2). The mass loss rate of a typical HJ, analogous to HD209458b, but was found to be strongly affected by m.field exceeding 0.3 Gauss. To investigate the effect of incoming SW on the escape regimes of expanding PW for sufficiently close star-planet systems, the self-consistent multi-fluid 1D HD model was upgraded to the 2D one with the inclusion of SW plasma flow (Shakhislamov et al. 2016, Khodachenko et al. 2017, Dwivedi et al., 2019). This work, as well as further development of a global 3D HD model of the whole star-planet system with self-consistent aeronomy and SW modelling blocks (Shakhislamov et al. 2018a, Berezutsky et al., 2018, Khodachenko et al. 2019) has been done in collaboration with FWF-RFBR project I2939-N27. It has been shown for the first time that the ENAs, crucial for the interpretation of Lyα in-transit absorption of HJs and warm Neptunes, produced due to charge exchange between PW atoms and SW protons, are generated in the region between the ionopause and bow-shock (Fig.SP06-3) where high densities of the interacting components are provided (Khodachenko et al. 2017). Terrestrial-type PMM – implications to atmospheric evolution. The PMM of Terrestrial paleo-magnetosphere for the late Hadean eon (~4.1 Gyr ago) was developed. The model runs were performed with different measured ancient Terrestrial dipole field varying between 12% and 100% of the present day value (Tarduno et al. 2010) with account of ancient SW data. The simulations show that Terrestrial magnetopause stand-off distance, RsE, was significantly smaller (as compared to the present-day value), varying from 3.43RE for the most extreme Hadean conditions (i.e., small dipole field, fast and dense SW) to 9.17RE for the least extreme case. The modelling also reveals that the polar caps were significantly broader than at present day and they affected the ion outflow via the poles. The latter was in the range from 20 to 500 times of the present day value for the slow rotating Sun and present day dipole and fast rotating Sun and 12% of the present day dipole, respectively. The PMM was also adapted to perform analogous simulations of the ancient Martian magnetosphere for 4.1-3.6 Gyr ago, depending on rotation rate of the early Sun and the strength of the ancient dipole field. The obtained results are relevant to the terrestrial type exoplanets in the habitable zones of Sun-like stars. Combined 3D PMM-Hybrid model of planetary magnetospheres. A novel approach to 3D modelling of planetary magnetospheres that involves a combination of the hybrid modelling concept (kinetics - for ions and heavy particles, fluid approximation - for electrons) and the PMM model has been elaborated jointly with the international cooperating partners from Moscow State University (Russia) and Aalto University (Finland). While both of the individual models have been applied in the past, their combination enabled overcoming of the known difficulty of hybrid models in revealing of self-consistent magnetic field and compensated the lack of plasma simulation in PMM. The combined model has been shown to reproduce the magnetosphere and magnetosheath of Mercury (as a prototype of a moderately close-orbit magnetized rocky exoplanet) controlled by the interplanetary medium conditions (Parunakian et al. 2017, Alexeev et al. 2018). The locations of bowshock and magnetopause determined in the simulations (Fig.SP06-4) were compared with measurements of the MESSENGER on-board magnetometers. The combined PMM-hybrid model was further applied to study plasma environment of ancient Mars and its magnetosphere under the conditions of slow rotating Sun for ~4.3 Gyr and ~3.8 Gyr ago, with 20 and 10 times higher EUV flux than that of the present day, respectively. The losses of C and O from the ancient Martian atmosphere were shown to increase with the increasing solar EUV flux. Within the scope of second research direction, the motion of particles inside a symmetric current sheet (CS) has been investigated. Particle trajectory method for self-consistent thin current sheets. Based on particle trajectories analysis, analytic solutions for the electric current density and plasma parameters in a thin current sheet (TCS) were obtained and compared with the results of numerical simulations. The particle trajectories have been initially calculated for a cold plasma assumption, i.e. neglecting the effects of the velocity thermal dispersion, and later were extended to the case of hot plasma (Sasunov et al. 2015a). It was shown that the TCS structure strongly depends on particle pitch-angle distribution and is determined by the competing diamagnetic and paramagnetic currents. The obtained analytic expression for TCS scaling agreed in the limiting cases with known estimates derived under more general assumptions. The proposed model describes well the observed characteristics of plasma layer in case when its current is created by contrstreaming particles with the same pitch-angle (Sasunov et al. 2015b). Based on conservation of particle magnetic moment, an analytic relation between the incoming particles flow velocity and plasma density in a TCS was obtained. This relation was confirmed with a dedicated PIC modeling (Sasunov et al. 2017). Further on, the particles motion in a strong gradient of magnetic field has been investigated. By inclusion of the effects of velocity thermal dispersion in the self-consistent description it was possible to generalize the TCS models to the case of arbitrary particle distribution functions. Self-consistent description of particle kinetics in CS. A new system of differential equations for the particle pitch-angle and rotation phase was derived from the analysis of particle trajectory in a given magnetic field (Sasunov et al. 2018). These equations provide an opportunity for analytic study of particle motion in arbitrary magnetic field, enabling an easy description of planetary magnetosphere CSs. The obtained self-consistent solutions for tangential CS reveal strong bifurcated profiles for the electric current and plasma density, with the bifurcation, controlled by the particle pitch-angle φ0 value (see Fig. SP06-5). This fact has been confirmed with modeling of an ensemble of non-interacting moving particles. The performed analysis gives a relation between two characteristic scales of the problem, thermal Larmor radius and inertial length. This relation, together with conservation of total pressure across TCS, allows predicting of TCS macro parameters, e.g., particle density and magnetic field. The obtained solutions for a self-consistent CS allow the reconstructing of particle distribution function on the basis of the corresponding electric current profile. This opens a way to probe particle distribution function and the related moments in the CS, using just the measured electric current distribution. The proposed methodology reveals also that in case of a down-dusk electric field the particle motion conserves the magnetic moment on specific segments of trajectory. It was shown that the current sheet can play a role of a lens, which focuses particles to specific pitch-angle values. The gained energy of accelerated particles in a TCS was found to depend linearly on the module of their TCS entry speed. Starspot variability as an X-ray radiation proxy. Stellar X-ray emission plays important role in the study of exoplanets as a proxy for stellar winds and as a basis for the prediction of EUV flux, unavailable for direct measurements, which in their turn are important factors for the mass-loss of planetary atmospheres. In spite of detection thresholds, limiting the number of stars with the directly measured X-ray fluxes, the known connection between sunspots and X-ray sources allows using of the starspot variability as an accessible proxy for the stellar X-ray emission. To realize this approach, the light curves of 1729 main-sequence stars with rotation periods 0.5d<P<30d and effective temperatures 3236K<Teff<7166K observed by Kepler mission were analyzed. It was found that the squared amplitude of the 1st rotational harmonic of stellar light-curve may be used as an activity index. This index reveals practically the same relation with the Rossby number as the ratio, Rx, of X-ray to bolometric luminosity. Thus, the regressions for the stellar X-ray luminosity Lx(P, Teff) and its related EUV analogue LEUV were obtained for the main-sequence stars (Fig. SP06-6). Cooperation within and outside of the NFN The national and international cooperation in SP06 included regular communication and exchange visits with world leading experts from the project topical area for the experience exchange and expert support. In some cases, short-term subcontracts for performing of project related tasks (e.g., computational model runs, codes development and expert support) were issued. The circle of national collaboration of SP06 involved SP04, SP07, SP08 teams of NFN consortium. The modelling of interaction of the expanding PW with the intrinsic planetary magnetic dipole field, and the aeronomy studies under different conditions of stellar XUV radiation and SW, as well as laboratory simulation of HJ’s magnetodisk  were performed in cooperation with scientists from the Institute of Laser Physics (ILP) of the Russian Academy of Sciences (RAS) in Novosibirsk, Russia. 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IWF Annual Report 2020  
Der jüngste Jahresbericht des IWF ist im PDF-Format erhältlich.
 
Scientists  
Dr. Stefan Kiehas (lead) Dr, Daniil Korovinskiy (PostDoc)  
Main Results  
Investigate the stability of a bent cross-tail current sheet We investigated the magnetotail’s current sheet stability to the cross-tail transversal mode utilizing analytical, as well as 2.5D linear (Korovinskiy et al., 2018c) and 3D non-linear MHD simulations (Korovinksiy et al., 2019). It is found that in plane current sheets, stable and unstable branches of the solution coexist. With increasing tilt angle, the growth rate rises and for sufficiently large tilt angles (~0.5 fmax), the stable solution becomes unobservably small compared to the unstable mode (see Fig. 1). For the maximum possible value of f ( ~40°, consisting of maximum of 33° from dipole tilt angle and 8° from non-radial propagation of the solar wind), the growth rate is 2.25 times bigger compared to the growth rate in a plane current sheet. Furthermore, it was found that the so-called double gradient instability corresponds to the compressible ballooning mode developing in a strongly stretched tail region. With downtail distance the velocity perturbation vector is rotating from the horizontal to the vertical direction, indicating the transition from the conventional ballooning mode to the double gradient mode. Investigate the interplay of kink and sausage modes in a bent current sheet In a 2.5D numerical simulation (Korovinskiy et al., 2018c), it was found that the symmetry of the solution of MHD equations in a bent current sheet is lost (cf. Fig. 2). For a plane current sheet (f=0), perturbations can be either symmetric (i.e., kink) or anti-symmetric (i.e., sausage) with respect to the current sheet center. In a bent current sheet, the solutions are asymmetric, consisting of a symmetric kink part and an anti-symmetric sausage part. With growing tilt angle the ratio of amplitudes of these two modes tends to unity. It was found that the asymmetry is most pronounced for f=20° and that perturbations are localized in the magnetotail’s summer hemisphere (for negative tilt angles, as used in the simulation). With this, in a bent current sheet, both kink and sausage modes coexist. Investigate the relation of bent current sheets to substorms In a statistical analysis (Kubyshkina et al., 2018) it was found that substorms occur almost two times more frequent when the IMF and solar wind parameters Bx and vz have the same sign as Bz. Since the magnetospheric current sheet bends for non-zero Bx and vz, one can derive a relation of current sheet bending and substorm onset out of this finding. In a 2.5D simulation (Korovinskiy et al., 2018c) the perturbation of the potential energy (δW) in plane and bent current sheet configurations is studied. Over the course of time, a concurrence of stable (δW>0) and unstable (δW<0) modes is found (see Fig. 3). For a plane current sheet the unstable mode dominates after ~ 1.5 to 2 hours, which is rather long compared to substorm timescales. However, in bent current sheets, the unstable mode dominates much faster – for the maximum possible tilt angle (~40°) it dominates after about 5 minutes. Hence, if bending is induced on a current sheet, it becomes fully unstable after a time period that is consistent with substorm onset time scales. The same situation is also found in 3D non-linear simulations (Korovinskiy et al., 2019). Investigate the influence of reconnection on the evolution of instabilities In a 3D nonlinear MHD simulation it was found that reconnection enhances the growth rate of the double gradient mode for a factor of about 2, but it does not shift the threshold of non-linear stabilization of the mode (see Fig. 4). With this, reconnection affects the growth rate but not the maximum amplitude of the perturbation. Investigate the relation of instabilities with entropy The field line entropy (S) was calculated in Korovinskiy et al. (2018c) for different angles of current sheet bending. S demonstrates a smooth monotonic profile along the current sheet center and increases tailward for any value of tilt angle f. Hence, the stability of a Kan-like current sheet to the transversal mode is not governed by the entropy criterion. Generalization of the instability criterion to bent current sheets Analogous to the characteristic flapping frequency (Equation (7) in Erkaev et al., 2007) we derived the necessary instability criterion for bent current sheets, reflected in Equation (41) in Korovinskiy et al., 2019. Under the simplifying assumptions of the Double Gradient Model, Equation (41) turns into the characteristic flapping frequency of that model.  Since Equation (41) includes several previously neglected terms, it is applicable in the near-Earth region (|vx|>|vz|) and also for bent current sheets. With this, equation (41) allows a representation for a much broader range of situations. Furthermore, this generalization allowed us to understand that the instability is controlled by the second derivative of the total pressure after ∂x ∂z in the near Earth region (where|vx|>|vz|) and by the second derivative of the total pressure after ∂z² more tailward (where| vx|<|vz|). Because the spatial variation of the total pressure is larger in the near-Earth region, the overall instability is controlled mainly by the mixed derivative of the total pressure. Energy budget of double gradient/ballooning instability The temporal energy evolution (kinetic, internal, magnetic, total energy) was investigated by means of a 3D non-linear MHD simulation (Korovinskiy et al. 2019). Three stages could be found: An initial settling phase, followed by a phase of exponential growth and finally a phase of non-linear stabilization. It is found that the kinetic energy is growing during the linear stage at the expense of the internal energy (see Fig. 6). The increase in magnetic energy is small compared to the increase of the kinetic energy and can therefore be neglected. The energy conservation within the computational box allowed the application of the energy principle of Bernstein (1958) and the mode identification  (compressible ballooning mode). Applicability of the Kan model In Korovinskiy et al. (2018b), a generalized Kan-like model was compared with the empirical T96 Tsyganenko model. It was found that parameters in the analytical model can be adjusted to fit a wide range of averaged magnetotail configurations (see Fig. 8). The best agreement between analytical and empirical models is obtained for the midtail at distances beyond 10–15 RE at high levels of magnetospheric activity. The essential model parameters (current sheet scale, current density) are compared to Cluster data of magnetotail crossings. The best match of parameters is found for single-peaked current sheets with mediu Field line curvature-related stability criterion for plane current sheets In the course of studies of the influence of the local total pressure maximum on current sheet stability (Korovinskiy et al., 2018a), a new criterion – related to the field line curvature – was derived. The plane current sheet is stable with respect to the MHD flapping mode, if the magnetic field curvature radius is decreasing in tailward direction before the X-line and increasing behind it. This criterion does not contradict the Schindler-Birn criterion (Schindler and Birn, 2004). Instead, it has advantages over it since it provides the necessary and sufficient condition for the mode stability and is more local, since it requires calculations only along the sheet center and not within the entire domain. Generalization of the double gradient model to oblique waves In Korovinskiy and Kiehas (2016) The double-gradient model of magnetotail flapping oscillations/instability is generalized for the case of oblique propagation in the equatorial plane. The transversal direction Y (in GSM reference system) of the wave vector is found to be preferable, showing the highest growth rates of kink and sausage double-gradient unstable modes (see Fig. 8). Growth rates decrease with the wave vector rotating toward the X direction. It is found that neither waves nor instability with a wave vector pointing toward the Earth/magnetotail can develop. These findings explain why flapping waves are observed in the Y-direction. Dispersion curve of flapping oscillations in plane current sheet In the simple double gradient model, the phase velocity is monotonically decreasing with wavenumber. However, by solving the exact solutions of linearized MHD equations (Korovinskiy et al. 2018a), it was found in that the dispersion curve of flapping oscillations can have a local maximum and hence the phase velocity as function of wave number can have a local maximum as well (see Fig. 9). Such behavior was observationally confirmed by Rong et al. (2018). Occurrence rate of fast flows observed by ARTEMIS In Kiehas et al., 2018, a five year statistical ARTEMIS study was conducted to investigate the occurrence rate of earthward and tailward fast flows near lunar orbit. It was found that a significant fraction of fast flows is directed earthward, comprising 43% (vx >400 km/s) to 56% (vx >100 km/s) of all observed flows (see Fig. 10). This suggests that near-Earth and midtail reconnection are equally probable of occurring on either side of the ARTEMIS downtail distance. For fast convective flows (vx >400 km/s), this fraction of earthward flows is reduced to about 29%, which is in line with reconnection as source of these flows and a downtail decreasing Alfvén velocity. Dawn-dusk asymmetry of fast flows observed with ARTEMIS More than 60% of tailward convective flows occur in the dusk sector (as opposed to the dawn sector), while earthward convective flows are nearly symmetrically distributed between the two sectors for low AL (>−400 nT) and asymmetrically distributed toward the dusk sector for high AL (< −400 nT) (see Fig. 11). This indicates that the dawn-dusk asymmetry is more pronounced closer to Earth and moves farther downtail during high geomagnetic activity. This is consistent with similar observations pointing to the asymmetric nature of tail reconnection as the origin of the dawn-dusk asymmetry of flows and other related observables. We infer that near-Earth reconnection preferentially occurs at dusk, whereas midtail reconnection (X >−60 RE) likely occurs symmetric across the tail during weak substorms and asymmetric toward the dusk sector for strong substorms, as the dawn-dusk asymmetric nature of reconnection onset in the near-Earth region progresses downtail.  
Outreach  
OUTREACH 2020: Contribution to European researchers night, 27 Nov 2020: A.J. Weiss: „Weltraumplasmaphysik" Press release for Möstl, C. et al. 2020, ApJ: https://www.derstandard.at/story/2000121809194/prognose-bis-zu-fuenf-sonnenstuerme-koennten-pro-monat-die-erde https://science.apa.at/site/natur_und_technik/detail.html?key=SCI_20201118_SCI39471352457555534 https://www.oeaw.ac.at/detail/news/wie-viele-stuerme-bringt-der-naechste-sonnenzyklus https://science.apa.at/rubrik/natur_und_technik/Neuer_Sonnenzyklus_IWF-_Forscher_rechnen_mit_mehr_Sonnenstuermen/SCI_20201118_SCI39391351457557682 https://science.orf.at/stories/3203014/ https://kurier.at/wissen/wissenschaft/neuer-zyklus-forscher-tippen-auf-mehr-sonnenstuerme/401101422 https://www.oe24.at/newsfeed/neuer-sonnenzyklus-iwf-forscher-rechnen-mit-mehr-sonnenstuermen/454550492 https://www.msn.com/de-at/nachrichten/other/neuer-zyklus-forscher-tippen-auf-mehr-sonnenst%c3%bcrme/ar-BB1b7VFV 2019: “When the Sun turns the power off”, Austrian Science Fund FWF project of the week, mentions C. Möstl, T. Amerstorfer, December 2019: https://scilog.fwf.ac.at/en/environment-and-technology/10647/when-the-sun-turns-the-power-off appeared in: https://science.apa.at/site/medizin_und_biotech/detail?key=SCI_20191216_SCI39471352452234340 http://m.raumfahrer.net/news/29122019161112.shtml https://phys.org/news/2019-12-in-silico-solar-storms-early.html  
Zusammenfassung  
Für den Onset geomagnetischer Teilstürme wird im Allgemeinen eine Instabilität in der Stromschicht des geomagnetischen Schweifs angenommen, die in der Übergangszone von schweifartigen zu dipolartigen magnetischen Feldlinien auftritt. Kandidaten für diese Instabilität sind die Ballooning/Interchange Instabilität (BICI) und Double-Gradient Instabilität (DGI). Bis dato wurden Untersuchungen dieser Instabilitäten unter der Annahme einer symmetrischen Stromschicht angenommen. Das interplanetare Magnetfeld, der Sonnenwind sowie die Neigung des geomagnetischen Dipols beeinflussen allerdings die Form und Inklination der Stromschicht. Unter realistischen Bedingungen ist die Stromschicht also geneigt und nicht symmetrisch. Dieser Effekt wurde bisher nicht in Betracht gezogen. Ziel dieses Projekts ist es, den Effekt einer geneigten Stromschicht auf den Onset von Teilstürmen und die Formation und Evolution von BICI und DGI zu untersuchen. Zu diesem Zweck wollen wir Antworten auf die folgenden wissenschaftlichen Fragen finden: (1) Begünstigt eine geneigte Stromschicht die Formation von Instabilitäten? (2) Können Instabilitäten in einer geneigten Stromschicht schneller anwachsen? (3) Begünstigt eine geneigte Stromschicht den Onset von Teilstürmen? (4) Beschleunigt magnetische Rekonnexion das Anwachsen von Instabilitäten? Somit wollen wir eine geneigte Stromschicht bezüglich (1) ihrer Stabilität (2) des Zusammenspiels verschiedener Wellentypen (3) ihrer Relation zu Teilstürmen und (4) den Einfluss von Rekonnexion auf die Evolution von Instabilitäten untersuchen. Um diese Ziele zu erreichen, planen wir analytische und numerische Methoden zu verwenden, sowie die Auswertung von Satellitendaten in enger Zusammenarbeit mit unseren internationalen Partnern miteinzubeziehen. Um die Bedeutung von Elektronenströmen und kinetischer Effekte während der Entstehung von Instabilitäten zu erforschen, planen wir ein analytisches Hall-MHD (HMHD) Modell der DGI für symmetrische und gebogene Stromschichtkonfigurationen zu verwenden. Diese Untersuchungen werden ergänzt durch nichtlineare 3D MHD und HMHD sowie 3D PIC Simulationen. Die nichtlineare BICI/DGI Evolution in symmetrischen und gebogenen Stromschichten wird mittels zuvor genannter 3D Simulationen (MHD/HMHD/PIC) durchgeführt. Das Zusammenspiel von unterschiedlichen Wellentypen wird mittels eines „magnetic filament“ Ansatzes gelöst um die gemeinsame zeitliche Entwicklung und mögliche Dominanz eines Wellentyps zu untersuchen. Für Untersuchungen des Zusammenspiels von Rekonnexion mit Instabilitäten wird ein 2.5D Elektronen-Hall MHD entwickelt um die Stabilität einer realistischen Magnetschweifkonfiguration zu untersuchen und die Elektronenstromschicht zu rekonstruieren. Die analytischen und numerischen Untersuchungen werden von Beobachtungen der THEMIS und MMS Missionen unterstützt. Diese Multi-Raumsonden-Missionen erlauben uns Instabilitätsstrukturen gleichzeitig von unterschiedlichen Beobachtungspunkten und über unterschiedliche Skalen – von der Elektronen zur MHD Skala – zu studieren. Es wird also ein umfassender Zugang gewählt, der theoretischen und numerische Studien sowie Datenanalyse unter einer realistischen Magnetschweifkonfiguration – die in bisherigen Studien nicht berücksichtigt wurde – kombiniert. Dieser Zugang kann Aufschluss über die Formation und Entwicklung von Teilsturm-relevanten Instabilitäten und die Rolle einer geneigten Stromschicht auf den Onset von Teilstürmen geben.  
Scientists  
Christian Möstl (lead) Andreas J. Weiss (PhD student)  
Publications  
Peer-reviewed PEER-REVIEWED in preparation Weiss, A.J., C. Möstl, T. Amerstorfer, R.L. Bailey, M. A. Reiss, J. Hinterreiter, U. V. Amerstorfer, M. Bauer, Multi-point analysis of coronal mass ejection flux ropes using combined data from Solar Orbiter, Bepi Colombo and Wind, A&A Solar Orbiter special issue, in prep., 2021. Möstl, C., Andreas J. Weiss, Erika Palmerio, Rachel L. Bailey, Martin A. Reiss, Tanja Amerstorfer, Jürgen Hinterreiter, Ute V. Amerstorfer, Maike Bauer, Noé Lugaz, Miho Janvier, and Pascal Demoulin, Dependency of in situ magnetic field signatures on the spacecraft trajectory through 3D flux rope solar coronal mass ejections, ApJ, in prep. 2021. D. Telloni, C. Scolini, C. Möstl, G. P. Zank, L. Zhao, Andreas J. Weiss, Martin A. Reiss et al., Study of two interacting Interplanetary Coronal Mass Ejections encountered by Solar Orbiter during its first perihelion passage, A&A Solar Orbiter special issue, in prep., 2021. O’Kane, J., Lucie M. Green, Emma E. Davies, Christian Möstl, Jürgen Hinterreiter, Johan L. Freiherr von Forstner, Andreas J. Weiss, David M. Long, and Tanja Amerstorfer, Origins of a stealth CME detected at Solar Orbiter, A&A Solar Orbiter special issue, in prep., 2021. E. Palmerio, E. K. J. Kilpua, M. Mierla, A. N. Zhukov, D. Barnes, O. Witasse, T. Nieves-Chinchilla, C. Möstl, L. Rodriguez, A. Isavnin, Beatriz Sanchez-Cano, E. Roussos, A. Masters, and N. P. Savani, Magnetic Structure and Propagation of a Solar Flux Rope from the Sun to Saturn, in prep., 2020. A. Isavnin, E. Palmerio, J. Magdalenic, C. Scolini, J. Pomoell, R. M. Winslow, E. K. J. Kilpua, C. Möstl, and S. Poedts, Multipoint 3D analysis of CME–CME–CME interaction,  A&A, in prep., 2020. submitted / in revision / revised Davies, E. E., C. Möstl, M.J. Owens, A.J. Weiss, T. Amerstorfer, J. Hinterreiter, M. Bauer, R.L. Bailey, M.A. Reiss, R.J. Forsyth, T.S. Horbury, H. O’Brien, V. Evans, V. Angelini, D. Heyner, I. Richter, H-U. Auster, W. Magnes, W. Baumjohann, D. Fischer, D. Barnes, J.A. Davies, and R.A. Harrison, In-Situ Multi-Spacecraft and Remote Imaging Observations of the First CME Detected by Solar Orbiter and Bepi Colombo, Astronomy & Astrophysics, revised, 2021. Freiher von Forstner, J., M. Dumbovic, C. Möstl, et al., Radial Evolution of the April 2020 Stealth Coronal Mass Ejection between 0.8 and 1 AU- A Comparison of Forbush Decreases at Solar Orbiter and Earth, Astronomy & Astrophysics, revised, 2021. published Möstl, C., Weiss, A. J., Bailey, R. L., Reiss, M. A., Amerstorfer, T., Hinterreiter, J., Bauer, M., McIntosh, S. W., Lugaz, N., & Stansby, D., Prediction of the In Situ Coronal Mass Ejection Rate for Solar Cycle 25: Implications for Parker Solar Probe In Situ Observations, Astrophys. J., 903, 92, 557 doi:10.3847/1538-4357/abb9a1, 2020. Weiss, A. J., Möstl, C., Amerstorfer, T., Bailey, R. L., Reiss, M. A., Hinterreiter, J., Amerstorfer, U. A., & Bauer, M., Analysis of Coronal Mass Ejection Flux Rope Signatures Using 3DCORE and Approximate Bayesian Computation, The Astrophysical Journal Supplement Series, 252, 1, 9, 2021. arXiv:2009.00327, https://ui.adsabs.harvard.edu/abs/2021ApJS..252....9W E. Palmerio, E. K. J. Kilpua, O. Witasse, D. Barnes, B. Sanchez-Cano, A. J. Weiss, T. Nieves-Chinchilla, C. Möstl, L. K. Jian, M. Mierla, A. N. Zhukov, J. Guo, L. Rodriguez, P. J. Lowrance, A. Isavnin, L. Turc, Y. Futaaja, M. Holmström, CME Magnetic Structure and IMF Preconditioning Affecting SEP Transport, Space Weather, in press, 2021. https://arxiv.org/abs/2102.05514  https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020SW002654 Dumbović, M., Vršnak, B., Guo, J., Heber, B., Dissauer, K., Carcaboso, F., Temmer, M., Veronig, A., Podladchikova, T., Möstl, C., Amerstorfer, T., & Kirin, A., Evolution of Coronal Mass Ejections and the Corresponding Forbush Decreases: Modeling vs. Multi-Spacecraft Observations, Solar Phys., 295, 104, doi:10.1007/s11207-020-01671-7, 2020. Dumbovic, M., J. Guo, M. Temmer, M. L. Mays, A. Veronig, S. Heinemann, K. Dissauer, S. Hofmeister, J. Halekas, C. Möstl, T. Amerstorfer, J. Hinterreiter, S. Banjac, K. Herbst, L. Holzknecht, M. Leitner, Unusual plasma and particle signatures at Mars and STEREO-A related to CME-CME interaction, Astrophys. J., 880, 18, 2019. doi:10.3847/1538-4357/ab27ca https://arxiv.org/abs/1906.02532 https://iopscience.iop.org/article/10.3847/1538-4357/ab27ca Good, S.W., E.K.J. Kilpua, A.T. LaMoury, R.J. Forsyth, J.P. Eastwood, C. Möstl, Self-Similarity of ICME Flux Ropes in the Inner Heliosphere, Solar Physics, 124, 4960-4982, 2019.  doi:10.1029/2019JA026475  https://arxiv.org/abs/1905.07227 https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2019JA026475 Talks at international conferences Andreas Weiss, Christian Möstl,  Mathew James Owens, Emma Davies, Timothy Simon Horbury, Helen O'Brien, Vincent Evans, Virginia Angelini, Werner Magnes, Tanja Amerstorfer, Martin Reiss, Rachel Bailey, Jürgen Hinterreiter and Maike Bauer, Multi-point magnetic flux rope analysis for the 2020 April 19 CME observed in situ by Solar Orbiter and Wind, AGU fall meeting (virtual), San Francisco, talk, Dec 2020. Noé Lugaz, Christina O Lee, David W Curtis, Daniel Cosgrove, Antoinette Broe Galvin, Robert J Lillis, Christian Möstl, Reka Moldovan Winslow, Nada A Al-Haddad, Charles J Farrugia, Davin Larson, Charles William Smith, Phyllis L Whittlesey, Roberto Livi, Lan Jian and Errol J Summerlin, A Smallsat Platform for Large-scale Interplanetary Studies (SPLIS): Rideshare Opportunities and Pathway to Sub-L1 Space Weather Missions, AGU fall meeting (virtual), talk, Dec 2020. Johan Lauritz Freiherr von Forstner, Mateja Dumbovic, Christian Möstl, Robert Elftmann, Zigong Xu, Jingnan Guo, Robert F Wimmer-Schweingruber, Tanja Amerstorfer, Jürgen Hinterreiter, Maike Bauer, Andreas Weiss, Javier Rodriguez-Pacheco, George C Ho, Timothy Simon Horbury0, Werner Magnes and The Solar Orbiter EPD Team, First CME and Forbush decrease observed at Solar Orbiter using EPD, AGU fall meeting (virtual), San Francisco, poster, Dec 2020. Noé Lugaz, Christina Lee, Toni Galvin, and Christian Möstl, A Smallsat Platform for Large-scale Interplanetary Studies (SPLIS), talk, European Space Weather Symposium (virtual), Belgium, Nov 2020. Mateja Dumbovic , Bojan Vrsnak , Jingnan Guo , Bernd Heber , Karin Dissauer , Fernando Carcaboso , Manuela Temmer, Astrid Veronig , Tatiana Podladchikova, Christian Möstl, Tanja Amerstorfer , and Anamarija Kirin, Evolution of coronal mass ejections and the corresponding Forbush decreases: modelling vs. multi- spacecraft observations, talk, European Space Weather Symposium (virtual),  Belgium, Nov 2020. Emma Davies, Mathew James Owens, Christian Möstl, Timothy Simon Horbury, Robert J Forsyth, Helen O'Brien, Vincent Evans, Virginia Angelini, Andreas Weiss, Martin Reiss, Rachel Bailey, Tanja Amerstorfer, Jürgen Hinterreiter, Ute Amerstorfer, Maike Bauer and Werner Magnes, In-Situ Multi-Spacecraft and Remote Imaging Observations of the First CME Detected by Solar Orbiter,  AGU fall meeting (virtual), poster,  Dec 2020. Mateja Dumbovic, Bojan Vrsnak, Jingnan Guo, Bernd Heber, Karin Dissauer, Fernando Carcaboso-Morales, Manuela Temmer, Astrid Veronig, Tatiana Podladchikova, Christian Möstl, Tanja Amerstorfer and Anamarija Kirin, Evolution of coronal mass ejections and the corresponding Forbush decreases: modelling vs. multi-spacecraft observations, AGU fall meeting (virtual), San Francisco, poster, Dec 2020. Palmerio, E., O.G. Witasse, T. Nieves-Chinchilla, D. Barnes, M. Mierla, A.J. Weiss, C. Möstl, A. Zhukov, L. Jian, B. Sanchez-Cano, L. Rodriguez, J. Guo, E. Roussos, A. Masters, G. Provan, A. Isavnin, P.J. Lowrance, L. Turc, K.E.J. Kilpua: Following the evolution of coronal mass ejections across the heliosphere, AGU Fall Meeting 2019, San Francisco, Dec 2019. Plaschke, F., T. Karlsson, C. Götz, C. Möstl, I. Richter, M. Volwerk, A. Eriksson, E. Behar, R. Goldstein: Magnetic holes at comet 67P, EGU General Assembly 2019, Wien, Apr 2019. Posters at international conferences Christian Möstl, Andreas Weiss, Martin Reiss, Rachel Bailey, Ute Amerstorfer, Tanja Amerstorfer, Jürgen Hinterreite, Maike Bauer, Scott William McIntosh, Noé Lugaz and David Stansby, Prediction of the In Situ Coronal Mass Ejection Rate for Solar Cycle 25: Implications for Parker Solar Probe In Situ Observations, AGU fall meeting, San Francisco (virtual),, poster, Dec 2020. Cyril Simon Wedlund, Martin Volwerk, Christian Mazelle, Christian Möstl, Diana Rojas-Castillo, Jared Espley, and Jasper Halekas, On Mirror Mode Waves at Mars: Results from MAVEN, European Planetary Science Congress, Sep 2020. Emma Davies, Christian Möstl, Mathew Owens, Timothy Horbury, Robert Forsyth , Helen O'Brien, Vincent Evans, Virginia Angelini, Andreas Weiss, Martin Reiss, Rachel Bailey, Tanja Amerstorfer, Jürgen Hinterreiter,  Ute Amerstorfer, Maike Bauer and Werner Magnes, In-situ multi-spacecraft and remote imaging observations of the first CME detected by solar orbiter and its geomagnetic impact, poster, European Space Weather Symposium (virtual), Belgium, poster, Nov 2020. Christian Möstl, Andreas J. Weiss, Rachel L. Bailey, Martin A. Reiss, Tanja Amerstorfer, Jürgen Hinterreiter, Maike Bauer, Scott W. McIntosh, Noe Lugaz, and David Stansby, Prediction of the in situ coronal mass ejection rate for solar cycle 25: Implications for Parker Solar Probe in situ observations, poster, European Space Weather Symposium (virtual), Belgium, poster, Nov 2020. Andreas Weiss, Christian Möstl, Tanja Amerstorfer, Rachel Bailey, Martin Reiss, Jürgen Hinterreiter, Maike Bauer, and Ute Amerstorfer, Analysis of coronal mass ejection flux rope signatures using 3DCORE and approximate Bayesian computation, poster, European Space Weather Symposium (virtual), Belgium, poster, Nov 2020. Dumbovic, M., Vrsnak, B., Guo, J., Heber, B., Dissauer, K., Carcaboso-Morales, F., Temmer, M., Veronig, A., Podladchikova, T., Möstl, C., Amerstorfer, T., & Kirin, A., CME evolution and the corresponding Forbush decrease: modelling vs multi-spacecraft observation, EGU General Assembly (virtual), Vienna, Apr 2020. Weiss, A., Möstl, C., Nieves-Chinchilla, T., Amerstorfer, T., Palmerio, E., Reiss, M., Bailey, R., Hinterreiter, J., Amerstorfer, U., & Bauer, M., Modelling coronal mass ejection flux ropes signatures using Approximate Bayesian Computation: applications to Parker Solar Probe, EGU General Assembly, Vienna, Apr 2020. Weiss, A. J., Möstl, C., Amerstorfer, U. V., Reiss, M. A., Amerstorfer, T., Hinterreiter, J., Bailey, R. L., Inferring initial conditions of coronal mass ejections using a fast data generative model and approximate bayesian computation, Machine Learning in Heliophysics 2019, Amsterdam, Sep 2019. Forstner, J., J. Guo, R.F. Wimmer-Schweingruber, M. Temmer, M. Dumbović, A. Veronig, C. Möstl, D. M. Hassler, C.J. Zeitlin, B. Ehresmann:  ICMEs propagating towards Mars observed in heliospheric imagers and their associated Forbush decreases at MSL/RAD, EGU General Assembly 2019, Wien, Apr 2019. Good, S., E. Kilpua, A. LaMoury, R. Forsyth, J. Eastwood, C. Möstl: Self-similarity of ICME flux ropes in the inner heliosphere, EGU General Assembly 2019, Wien, Apr 2019. Möstl, C., T. Amerstorfer, M.A. Reiss, R.L. Bailey, J. Hinterreiter, U.V. Amerstorfer, N. Lugaz: Predicted statistics of coronal mass ejections observed by Parker Solar Probe and forward modeling of their in situ magnetic field, EGU General Assembly 2019, Wien, Apr 2019. Open source materials and codes Codes Downloading and handling data from various space missions: Weiss, A. J., Heliosat, https://github.com/ajefweiss/HelioSat Creating solar storm catalogs from spacecraft data: Möstl, C., heliocats, https://github.com/cmoestl/heliocats Animations Möstl, C., et al., Parker Solar Probe double crossings simulations: https://www.youtube.com/watch?v=VNC2lsw-UtU Möstl, C., et al. Spacecraft Data and positions: https://www.youtube.com/watch?v=py5h_nNIcjQ&t=6s Möstl, C., Predicted orbits of Parker Solar Probe, BepiColombo, and Solar Orbiter 2018-2025 (HCI, HEEQ), figshare. Media, 2019. https://doi.org/10.6084/m9.figshare.7364132.v1 also available on youtube: https://www.youtube.com/watch?v=UZ0ISGJXA_M&t=122s https://www.youtube.com/watch?v=0ybvOYEl9VU&t=79s Data sets: Material for Möstl et al. 2020 ApJ: https://figshare.com/articles/journal_contribution/Data_and_code_for_the_paper_M_stl_et_al_2020_ApJ/12563765 Solar wind data suitable for machine learning: https://figshare.com/articles/dataset/Solar_wind_in_situ_data_suitable_for_machine_learning_python_numpy_arrays_STEREO-A_B_Wind_Parker_Solar_Probe_Ulysses_Venus_Express_MESSENGER/12058065 Solar wind data suitable for catalog production: https://figshare.com/articles/dataset/Coronal_mass_ejection_in_situ_data_for_creating_catalogs_and_statistics_MESSENGER_VEX_Wind_STEREO-A_B_MAVEN_PSP_2007-2019/11973693 STEREO heliospheric imagers CME arrival catalog: https://helioforecast.space/arrcat https://figshare.com/articles/dataset/Arrival_catalog_of_coronal_mass_ejections_observed_with_STEREO_Heliospheric_Imagers_HELCATS_ARRCAT_2_0_/12271292   ICME catalog: https://helioforecast.space/icmecat https://figshare.com/articles/dataset/HELCATS_Interplanetary_Coronal_Mass_Ejection_Catalog_v2_0/6356420 Möstl, C., T. Amerstorfer, A. J. Weiss, R. L. Bailey, M. A. Reiss, J. Hinterreiter, N. Lugaz, U.V. Amerstorfer, Poster for EGU 2019: Predicted statistics of coronal mass ejections observed by Parker Solar Probe and forward modeling of their in situ magnetic field. figshare. Dataset and media. https://doi.org/10.6084/m9.figshare.7901786.v2  
Zusammenfassung  
Die Sonne produziert sogenannte Sonnenstürme, Wolken aus Plasma die starke Magnetfelder enthalten und die immer wieder aus ihrer äußersten Schicht ausgestoßen werden. Sie werden im Sonnenwind zwischen den Planeten gebremst und expandieren stark. Falls sie auf die Erde treffen werden Nordlichter deutlich intensiviert, doch ihr Impakt kann sogar in seltenen Fällen zu Problemen mit der Stromversorgung und globalen Navigations-Systemen führen. In diesem Projekt arbeiten wir an einem besseren Verständnis der Magnetfelder in deren Kern, die eine relativ geordnete Struktur aufweisen und die im Kontrast stehen zur turbulenten Umgebung des Sonnenwinds in dem sie sich ausbreiten. Wenn so ein Kern auf das Erdmagnetfeld trifft, muss das Magnetfeld in die korrekte Richtung zeigen um Energie auf das Erdmagnetfeld übertragen zu können. Daher müssen diese geordneten Strukturen in den Kernen besser verstanden werden, um ihre Effekte auf die Erde und andere Planeten besser vorhersagen zu können.  Wir werden eine neue Art von Simulation weiterentwickeln welche diese Kerne beschreibt, basierend auf der Hypothese dass es sich um extrem grosse gebogenen Röhren handelt, die eine spezielle Struktur des Magnetfelds beinhalten. Dies hat mehrere Vorteile - unter anderem können unsere Berechnungen sehr schnell erfolgen womit die Bereiche von vielen Parametern getestet werden können. Auch ist das Modell auf eine Art und Weise entworfen sodass es zukünftig direkt für die Vorhersage von Sonnenstürmen verwendet werden kann. Die erst kürzlich neu verfügbaren Daten von vielen Raumsonden im Sonnenwind zwischen Sonne und Erde werden in unserem Projekt zu bahnbrechenden neuen Erkentnissen führen, weil wir unser Modell zum ersten mal mit mehreren Beobachtungen desselben Sonnensturms, zum Beispiel bei Merkur, Venus und Erde, testen können. Dies erlaubt die freien Parameter der Simulation stark einzugrenzen um robuste Resultate zur Ausbreitung und Entwicklung von Sonnenstürmen zwischen Sonne und Erde zu finden. Als Bonus wird 2018 voraussichtlich die erste Raumsonde gestartet welche sich zeitweise zwischen der Sonne und Merkur befinden wird – die Parker Solar Probe. Dies könnte zu noch nie dagewesenen Beobachtungen von Sonnenstürmen nahe an der Sonne führen. Unsere Simulation ist perfekt geeignet diese Beobachtungen zu interpretieren, die entscheidende Hinweise darauf geben könnten wie Sonnenstürme auf der Sonne entstehen und wie sie sich danach bis zur Erde ausbreiten.  
Nano-analysis of cometary dust – uncovering the building blocks of the Solar System  
Project Leader Dr. Thurid Mannel Pricipial Investigator Dr. Thurid Mannel E-Mail thurid.mannel[at]oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 05.10.2015 Project duration Start: 01.03.2016   End: 31.10.2020 Scientific field(s) 1223 (Space Science): 60%   1245 (Nano Technology): 20%   1238 (Surface Physics): 20% Keywords Cometary Dust   Atomic Force Microscopy   Rosetta   Morphology   Size distribution   Magnetic force microscopy  
Multi-scale analysis of magnetotail dipolarizations  
Project Leader Dr. Martin Volwerk Pricipial Investigator Dr. Daniel Schmid E-Mail martin.volwerk[at]oeaw.ac.at   daniel.schmid[at]oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 06.05.2013 Project duration Start: 01.10.2013   End: 31.12.2016 Scientific field(s) 103 (Physics, Astronomy): 100% Keywords Space Physics   Magnetotail   Dipolarization  
Electron dynamics and magnetotail structure  
Principal Investigator Dr. Rumi NAKAMURA E-Mail rumi.nakamura[at]oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 06.10.2014 Project duration Start: 01.05.2015   End: 29.02.2020 Scientific field(s) 103 (Physics, Astonomy): 80%   102 (Informatics): 10%   101 (Mathematics): 10% Keywords Magnetotail   Current Sheet   Magnetic Reconnection   bursty bulk flows   Cluster, MMS  
LIGHTNING ON PLANETS WITH FOCUS ON SATURN  
...imagine a thunderstorm with a diameter around 3000 km and lightning bolts whose radio signals are 10.000 times stronger compared to their terrestrial counterparts. These are the SEDs (Saturn Electrostatic Discharges) which are investigated in this project... And in December 2010 a giant thunderstorm started in Saturn's northern hemisphere with a latitudinal extension of 10,000 km (see below)!  
ANALYSIS OF FINE STRUCTURES IN AURORAL RADIO EMISSIONS  
In the frame of this international Austrian-Czech research project we will jointly investigate spectral fine structures of planetary auroral radio emissions seen in high temporal resolution data from three different spacecraft at three different planets:       Cluster satellites at Earth       Juno spacecraft at Jupiter       Cassini spacecraft at Saturn  
Thin Current Sheets in the Earth's Magnetotail  
Principal Investigator Dr. Rumi NAKAMURA E-Mail rumi.nakamura[at]oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 22.04.2010 Project duration Start: 20.06.2010   End: 19.02.2014 Scientific field(s) 1223 (Space exploraton): 40%   1228 (Plasma physics): 40%   1151 (Numerical computation): 20% Keywords Magnetotail   Plasma Sheet, Current Sheet   Magnetic Reconnection   Cluster, THEMIS  
Determination of the three dimensional geometry of the magnetic reconnection ion diffusion region  
Principal Investigator Dr. Rumi NAKAMURA E-Mail rumi.nakamura[at]oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 30.12.2011 Project duration Start: 01.04.2012   End: 31.12.2015 Scientific field(s) 1228 (Plasma physics): 50%   1223 (Space exploraton): 30%   1505 (Geophysics): 10%   1205 (Astrophysics): 10% Keywords Magnetic Reconnection   Multi-point data analysis Ions diffusion region   Hall current, Magnetotail current sheet   Cluster  
The evolution of solar storms in the inner heliosphere  
Principal Investigator Dr. Christian Möstl E-Mail christian.moestl[at]oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 30.09.2013 Project duration Start: 01.03.2014   End: 28.02.2019 Scientific field(s) 103 (Physics, Astronomy): 100% Keywords coronal mass ejections   geomagnetic storms   STEREO   Heliospheric Imagers   solar-terrestrial relations   space weather  
Magnetic Rossby waves on the Sun  
Principal Investigator Dr. Teimuri ZAQARASHVILI E-Mail teimuri.zaqarashvili[at]oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 01.06.2009 Project duration Start: 01.09.2009   End: 31.07.2013 Scientific field(s) 1205 (Astrophysics): 30%   1223 (Space Research): 25%   1228 (Physics of plasma): 40%   1151 (Numerical computation): 5% Keywords solar chromosphere and corona   MHD waves and oscillations   partially ionized plasmas   energy transport and release in solar atmosphere  
Study of the energy transport and release processes in the solar chromosphere and corona with inclusion of the effects of partially ionized helium  
Principal Investigator Dr. Maxim L. KHODACHENKO E-Mail maxim.khodachenko[at]oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 01.06.2009 Project duration Start: 01.09.2009   End: 31.07.2013 Scientific field(s) 1205 (Astrophysics): 30%   1223 (Space Research): 25%   1228 (Physics of plasma): 40%   1151 (Numerical computation): 5% Keywords solar chromosphere and corona   MHD waves and oscillations   partially ionized plasmas   energy transport and release in solar atmosphere  
Multispacecraft observations of Jovian DAM  
Principal Investigator Dr. Mykhaylo Panchenko E-Mail mykhaylo.panchenko[at]oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 04.12.2011 Project duration Start: 01.02.2012   End: 31.05.2015 Scientific field(s) 103 (Physik, Astronomie): 95%   102 (Informatik): 5% Keywords Jupiter's magnetosphere   Periodic bursts of non-Io DAM, Jovian Decametric radio emission (DAM)   Nonthermal planetary radio emission, Solar wind   Internal magnetospheric dynamics  
Bent current sheet: A possible catalyzer to trigger substorm onset  
Principal Investigator Dr. Stefan Kiehas E-Mail Stefan.kiehas[at]oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 23.06.2014 Project duration Start: 01.07.2015   End: 31.07.2019 Scientific field(s) 123 ( 50%) 1228 (20%) 1222(20%) 1601 (10%) Keywords Double gradient instability   Interchange instability   Bent current sheet   Magnetospheric substorms   Ballooning instability   Magnetic reconnection  
Outreach  
2019: U.V. Amerstorfer, Space Weather, talk for school-children, GIBS school Graz, Austria, June 2019  
Home  
MODELING THE MAGNETIC CORES OF SOLAR STORMS Principal Investigator Dr. Christian Möstl E-Mail christian.moestl[at]oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 25.06.2018 Project duration Start: 01.02.2019   End: 31.01.2022 Scientific field(s) 103 (Physics, Astronomy): 100% Keywords solar coronal mass ejections   Heliophysics System Obersvatory   heliophysics   interplanetary magnetic fields   magnetic flux ropes   space weather  
Scientists  
Christian Möstl (lead) Rachel Bailey (PostDoc at at IWF and later at national collaborator ZAMG) Martin Reiss (PostDoc)  Ute Amerstorfer (PostDoc)  Roman Leonhardt (national collaborator, ZAMG)  
Publications  
PEER-REVIEWED in preparation Bailey, R.L, et al. GICs, 2021 Reiss, M. A., C. Möstl, R.L. Bailey, Amerstorfer, U.V., A.J. Weiss, M.A. Reiss, T. Amerstorfer, J. Hinterreiter, M. Bauer, Predicting the magnetic flux rope fields at the Sun-Earth L1 point, Space Weather, in prep., 2021. submitted / in revision / revised Bailey, R. L., Reiss, M. A., Arge, C. N., Möstl, C., Owens, M. J., Amerstorfer, U. V., Henney, C. J., Amerstorfer, T., Weiss, A. J., & Hinterreiter, J., Improving ambient solar wind model predictions with machine learning, Space Weather, revised, 2021. https://arxiv.org/abs/2006.12835 Reiss, M.A., K. Muglach, C. Möstl, C. Arge, R. L. Bailey, et al., The Observational Uncertainty of Coronal Hole Boundaries in Automated Detection Schemes, ApJ Letters, submitted, 2021. published / in press Allen, R. C., G. C. Ho, G. M. Mason, L. K. Jian, S. K. Vines, S. D. Bale, A. W. Case, M. E. Hill, C. J. Joyce, J. C. Kasper, K. E. Korreck, D. M. Malaspina, D. J. McComas, R. McNutt, C. Möstl, D. Odstrcil, N. Raouafi, and M. L. Stevens, SIR/CIRs in the Parker Solar Probe Era, Astronomy & Astrophysics, in press, 2021. Bailey, R. L., Möstl, C., Reiss, M.  A., Weiss, A. J., Amerstorfer, U. V., Amerstorfer, T., et al., Prediction of Dst during solar minimum using In situ measurements at L5, Space Weather, 18, e2019SW002424, 2020. https://doi.org/10.1029/2019SW002424  (open access) https://arxiv.org/abs/2005.00249 Reiss, M. A., MacNeice, P. J., Muglach, K., Arge, C. N., Möstl, C., Riley, P., Hinterreiter, J., Bailey, R. L., Weiss, A. J., Owens, M. J., Amerstorfer, T., & Amerstorfer, U., Forecasting the Ambient Solar Wind with Numerical Models. II. An Adaptive Prediction System for Specifying Solar Wind Speed near the Sun, The Astrophysical Journal, 891, 2, 165, 2020. https://doi.org/10.3847/1538-4357/ab78a0/      https://arxiv.org/abs/2005.00249 Talks at international conferences Martin Reiss, Peter J MacNeice, Karin Muglach,, Charles Nickolos Arge, Christian Möstl, Pete Riley, Rachel Bailey, Jürgen Hinterreiter, Andreas Weiss, Mathew James Owens, Carl J Henney, Ute Amerstorfer and Tanja Amerstorfer, An Adaptive Prediction System for Specifying Solar Wind Conditions Near the Sun, AGU fall meeting (virtual), San Francisco, poster, Dec 2020. Martin A. Reiss: Ensemble modeling techniques in ambient solar wind modeling, iSWAT meeting, Feb 2020, Cape Canaveral, USA. Eastwood, J.P., C.M. Carr, C. Palla, W. Magnes, G. Berghofer, A. Valavanoglou, R. Nakamura, C. Möstl: Magnetic field measurements at L5 and development of the Lagrange magnetometer, Transitioning Research and Instrument Expertise in Heliophysics into Space Weather Monitoring Capabilities at L1 and L5, London, Jun 2019.   Posters at international conferences Maria Kuznetsova, Anna Belehaki, Mario Mark Bisi, Sean Bruinsma, Shing F Fung, Alexi Glover, Manuel Grande, Jingnan Guo, Insoo Jun, Jon Linker, Ian Robert Mann, Arnaud Masson, Anne Michelle M Mendoza, Sophie A. Murray, Dibyendu Nandy, Hermann J Opgenoorth, Alexei A Pevtsov, Christina Plainaki, Martin Reiss, Eric K Sutton, Manuela Temmer, Ilya G Usoskin, Zhonghua Yao, Stephanie Yardley, Yihua Zheng and Nandi, Dibyendu, COSPAR International Space Weather Action Teams: Addressing Challenges Across the Field of Space Weather, AGU fall meeting (virtual), poster, Dec 2020. Rachel Bailey, Roman Leonhardt, Christian Möstl, Martin Reiss, Andreas Weiss, Dennis Albert, Philipp Schachinger and Georg Achleitner, Predicting GICs from L solar wind data using geophysical methods in combination with machine learning, AGU fall meeting (virtual), poster, Dec 2020. Rachel Bailey, Martin Reiss, Christian Möstl, Ute Amerstorfer, Cyril Simon Wedlund, Tanja Amerstorfer, Andreas Weiss, Jürgen Hinterreiter, Jingnan Guo, Johan von Forstner, David Barnes, Jackie Davies, and Richard Harrison, A comprehensive catalogue of solar wind properties and events in the inner heliosphere, European Planetary Science Congress, Sep 2020. Alexander Lavrukhin, David Parunakian, Dmitry Nevskiy, Ute Amerstorfer, Andreas Windisch, Sahib Julka, Christian Möstl, Martin Reiss, and Rachel Bailey, Automatic detection of magnetopause and bow shock crossing signatures in MESSENGER magnetometer data, European Planetary Science Congress, Sep 2020. Hannah Rüdisser, Andreas Windisch, Ute V. Amerstorfer, Tanja Amerstorfer, Christian Möstl, Rachel L. Bailey, Automatic Detection and Classification of ICMEs in Solar Wind Data, poster, European Space Weather Symposium (virtual), Belgium, poster, Nov 2020. Martin Reiss, Manuela Temmer, Karin Muglach, Maria Kuznetsova, Peter MacNeice, Richard Mullinix, Rui Pinto, Charles N. Arge, Sergio Dasso, Chiu Wiegand, Lan Jian, Christian Möstl, Evangelia Samara, Camilla Scolini, Barbara Perri, Mathew Owens, Pete Riley, and Rachel Bailey, The COSPAR ISWAT initiative for  open validation analysis of ambient solar wind models, poster, European Space Weather Symposium (virtual), Belgium, poster, Nov 2020. Rachel Bailey, Roman Leonhardt, and Christian Möstl, Forecasting local GICs from solar wind data using a combination of geophysical and machine learning methods, poster, European Space Weather Symposium (virtual), Belgium, poster, Nov 2020. Reiss, M., Bailey, R., Arge, N., Möstl, C., Owens, M., & Henney, C., Improving Ambient Solar Wind Model Predictions for Earth Using Machine Learning, AAS/Solar Physics Division Meeting (virtual), poster, Aug 2020. Möstl, C., Bailey, R. L., Amerstorfer, U. V., Amerstorfer, T., Weiss, A. J., Reiss, M. A., Hinterreiter, J., & Bauer, M., HelioCast - a  real time test environment to enhance space weather prediction at Earth, EGU General Assembly (virtual), Vienna, Apr 2020. Reiss, M., MacNeice, P., Muglach, K., Arge, N., Möstl, C., Riley, P., Hinterreiter, J., Bailey, R., Weiss, A., Owens, M., Amerstorfer, T., & Amerstorfer, U., An Adaptive Prediction System for Specifying Solar Wind Conditions Near the Sun, EGU General Assembly (virtual), Vienna, Apr 2020. Bailey, R., Möstl, C., Reiss, M., Weiss, A., Amerstorfer, U., Amerstorfer, T., Hinterreiter, J., & Bauer, M., Forecasting the Dst index from L5 in-situ data using PREDSTORM: accuracy and applicability, EGU General Assembly, Vienna, Apr 2020. Amerstorfer, U., Möstl, C., Bailey, R., Weiss, A., Reiss, M., Amerstorfer, T., Hinterreiter, J., & Bauer, M., Predicting the magnetic flux rope fields at the Sun-Earth L point, EGU General Assembly (virtual), Vienna, Apr 2020. Reiss, M., P.J. MacNeice, K. Muglach, M.S. Kirk, C.N. Arge, C. Möstl: Assessing the uncertainty of coronal hole boundary locations, AGU Fall Meeting 2019, San Francisco, Dec 2019. Möstl, C., U.V. Amerstorfer, R.L. Bailey, A.J. Weiss, T. Amerstorfer, J. Hinterreiter, M.A. Reiss: PREDSTORM - a new L1 solar wind and magnetic storm prediction system, Machine Learning in Heliophysics 2019, Amsterdam, Sep 2019. Bailey, R.L., C. Möstl, U.V. Amerstorfer, T. Amerstorfer, A.J. Weiss, J. Hinterreiter, M.A. Reiss, D. Albert: PREDSTORM and SOLARWIND2GIC: Forecasting of space weather effects and geomagnetically induced currents with Python, Machine Learning in Heliophysics 2019, Amsterdam, Sep 2019. Amerstorfer, U.V., C. Möstl, R.L. Bailey, A.J. Weiss, T. Amerstorfer, J. Hinterreiter, M.A. Reiss, M. Bauer: Forecasting of magnetic flux rope fields at the Sun- Earth L1 point, Machine Learning in Heliophysics 2019, Amsterdam, Sep 2019. Amerstorfer, U.V., C. Möstl, R.L. Bailey, A. J. Weiss, T. Amerstorfer, J. Hinterreiter: PREDSTORM - an empirical magnetic storm forecast pipeline, Towards Future Research on Space Weather Drivers, San Juan, Jul 2019. Bailey, R.L., C. Möstl, U.V. Amerstorfer, T. Amerstorfer, A.J. Weiss, R. Leonhardt: Predicting GICs from L1 solar wind data using recurrent neural networks, EGU General Assembly 2019, Wien, Apr 2019. Talks at project meetings Magnes, W., G. Berghofer, C. Möstl, R. Bailey, C. Carr, J. Eastwood, C. Palla, T. Horbury: Lagrange ISRR Kick-Off MAG Presentation, LAGRANGE Mission Intermediate System Requirements Review (ISRR), Noordwijk, Jul 2019. Session convening Martin Reiss: Coronal Hole Boundary Working Team Session, COSPAR ISWAT Inaugural Working Meeting, Cape Canaveral, Feb 2020. https://docs.google.com/document/d/1lNcB7qfBnVq30hE0-BhlkRNMwdIKmcST6Fk96hv13PE/edit?usp=sharing Martin Reiss, Manuela Temmer: Ambient Solar Wind Validation Team Session, COSPAR ISWAT Inaugural Working Meeting, Cape Canaveral, Feb 2020. https://docs.google.com/document/d/1VHZt3OEe17zxb8pAcRKWQNDeecbYNGO-bY6r-KQ4tZ0/edit Martin Reiss, Christina Kay, Manuela Temmer: CME propagation through evolving ambient solar wind, COSPAR ISWAT Working Meeting, Cape Canaveral, Feb 2020. https://docs.google.com/document/d/1-sOw9uEFjbBsbLURQhbl_RMMQ2bpUPOnKztzrBA8GTA/edit Open source materials and codes Code for the results and figures presented in Bailey et al. 2020: https://github.com/helioforecast/Papers/tree/master/Bailey2020_L5DstPrediction PREDSTORM prediction technique for the solar wind with data from STEREO-A, L1 or a future possible L5 mission: https://github.com/helioforecast/Predstorm Aurora model OVATION Prime 2010 as open source (update to 2013 version under development): https://github.com/helioforecast/auroramaps SIR catalog: https://helioforecast.space/sircat https://figshare.com/articles/dataset/Helio4Cast_SIRCAT_1_0/12416906 Aurora prediction: https://helioforecast.space/aurora Solar wind prediction: https://helioforecast.space/solarwind Solar cycle predictions: https://helioforecast.space/solarcycle  
Zusammenfassung  
Das Ziel dieses Projekts ist die Vorwarnzeit für die Effekte von Sonnenstürmen bei der Erde zu verbessern. Denken sie an die Meteorologie – doch unsere Forschungen drehen sich nicht um das Wetter das wir tagtäglich erfahren, sondern wir machen Vorhersagen für den Sonnenwind, der um das Erdmagnetfeld fließt. Sonnenstürme sind Wolken aus Plasma und Magnetfeldern die aus der Sonnenatmosphäre mit Geschwindigkeiten von Millionen Kilometern pro Stunde ausgeworfen werden. Falls so ein solarer Super-Sturm die Erde trifft, was schätzungsweise alle 100 Jahre passiert, könnten Infrastrukturen wie Stromnetze und Satelliten ausfallen, und Flug-Personal und Astronauten wären erhöhter Strahlung ausgesetzt. Sonnenstürme können ein Teil ihrer Energie auf das Erdmagnetfeld übertragen, und ein geomagnetischer Sturm entsteht. Dies kann wunderschöne Nordlichter hervorrufen, aber auch Technologien beeinträchtigen, die für unser tägliches Leben von hoher Wichtigkeit sind, wie die Stromversorgung und GPS. Um diese potentiell destruktiven Effekte besser zu vermeiden ist eine Vorhersage des Sonnenwinds am Sonne-Erde L1 Punkt von größter Wichtigkeit, und kann als Schlüsseltechnologie in diesem Feld angesehen werden, ähnlich wie wiederverwertbare Raketen oder Gen-Scheren in anderen Wissensgebieten. In diesem Projekt nutzen wir die Verfügbarkeit von über 40 Jahren an Sonnenwind-Daten, womit wir die Ergebnisse unserer eigenen Simulationen von Sonnenstürmen mit maschinellem Lernen verknüpfen können. Damit können wir die Simulationen automatisch auswählen welche die Realität am besten beschreiben. Dies wird eine Vorhersage der Entwicklung eines geomagnetischen Sturms mit einer Vorwarnzeit von bis zu 2 Tagen ermöglichen. Wir werden diese Ergebnisse mit einem bestehenden Modell für Nordlichter verbinden, welches der Öffentlichkeit ermöglichen wird besser vorauszusehen wann und wo die Aurora zu sehen sein wird. Weiters werden wir die Sonnenwind-Vorhersagen mit einem Modell der Zentralanstalt für Meteorologie und Geodynamik für geomagnetisch induzierte Ströme verknüpfen, welches wiederum helfen könnte Stromausfälle zu vermeiden. Die Vorhersagen werden zuerst mit bereits bestehenden Daten entwickelt und getestet, und danach in Echtzeit angewendet. Weiters werden wir mit bereits bestehenden Daten mögliche, zukünftige interplanetary Kleinsatelliten (CubeSats) auf ihre Tauglichkeit prüfen unsere Vorhersagen weiter zu verbessern. Eine Unterstützung dieses Projekts würde daher Österreichs Rolle einer international führenden Nation in der Vorhersage und Modellierung des Weltraumwetters konsolidieren und weiter ausbauen.  
Scientists  
Tanja Amerstorfer (lead) Maike Bauer (master student) Jürgen Hinterreiter (PhD student)  
Verbesserte Vorwarnzeit für geomagnetische Stürme  
Principal Investigator Dr. Christian Möstl E-Mail christian.moestl[at]oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 26.11.2018 Project duration Start: 01.03.2019   End: 28.02.2023 Scientific field(s) 103 (Physics, Astronomy): 40%   105 (Geosciences): 30%   102 (Informatics): 30% Keywords space weather forecasting   aurora   geomagnetically induced currents   geomagnetic storms   solar coronal mass ejections   solar wind  
Abstract  
During the last years, alerts of solar storms on their way to Earth have been frequently sent out by the media. Solar storms or so-called coronal mass ejections (CMEs), are formations consisting of charged particles and an embedded magnetic field structure. While slow CMEs need three to five days, the fastest can reach the Earth’s magnetosphere within one day or less, having impact speeds of up to 10 million kilometers per hour. The consequences of these impacts are geomagnetic storms, which can damage satellites as well as lead to large-scale power outages on the ground, to name only two possible effects. Accurately predicting arrival times and speeds of CMEs is quite difficult. Because of limited observational possibilities, errors in the arrival time of 10–20 hours are common. Besides the high prediction errors, false alarms are an even more important issue. False positive alarms are alerts where CMEs predicted to arrive Earth actually miss, false negative alarms are CMEs that are not predicted to arrive but actually hit. The goal of this project is the enhancement of a CME prediction tool, that currently assumes an elliptical shape of the CME front and a uniform, unstructured background solar wind, which causes a deceleration or acceleration of the CME. The basis of this prediction tool are observations from the NASA mission “Solar TErrestrial RElations Observatory” (STEREO) and its heliospheric imagers. These heliospheric imagers are wide-angle cameras that provide a side view on the CME during its journey through interplanetary space. The aim of this project is to uncouple the tool from the rigid ellipse shape and to include a variable background solar wind speed. By allowing a variation of the CME shape during propagation, possible influences of high speed solar wind streams or other CMEs can be taken into account when forecasting a CME arrival. Another important improvement is the applicability of the tool to observations of polarized light that can be directly related to the shape of the CME, which is further incorporated into the prediction utility. We expect a significant reduction of the prediction errors in CME arrival time and speed at Earth as well as a decrease of today’s false alarm rate.  
Scientists  
Takuma Nakamura (Lead) Rumi Nakamura (Staff Scientist) Ferdinand Plaschke (Staff Scientist)  
International collaborations  
Hiroshi Hasegawa (ISAS/JAXA) Kevin Genestreti (SwRI) Yi-Hsin Liu (Dartmouth College)  
Predicting solar storm arrivals at Earth (Die Vorhersage von Sonnenstürmen bei der Erde)  
Principal Investigator Dr. Tanja Amerstorfer E-Mail tanja.amerstorfer[at]oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 07.05.2018 Project duration Start: 01.07.2018   End: 30.06.2021 Scientific field(s) 103 (Physics, Astronomy): 100% Keywords space weather forecasting   space weather   heliospheric evolution of coronal mass ejections   predicting solar storms, polarized heliospheric imaging   future space missions  
Erika Kaufmann  
Dr. Erika Kaufmann Scientist T +43 (316) 4120 - 653 Erika.Kaufmann(at)oeaw.ac.at Room 2.a.9  
Andrea Stefania Acaro Narvaez  
Andrea Stefania Acaro Narvaez, BSc MSc Student T +43 (316) 4120 - 579 Andrea.Acaro(at)oeaw.ac.at Room 1.d.2  
Home  
Energy transfer across magnetospheric boundary layers Principal Investigator Dr. Takuma Nakamura E-Mail takuma.nakamura@oeaw.ac.at Address Schmiedlstrasse 6, 8042 Graz, AUSTRIA Research Institution Space Research Institute of the Austrian Academy of Sciences Approval date 30.09.2019 Project duration Start: 01.03.2020   End: 29.02.2024 Scientific field(s) 103 (Physics, Astronomy): 95%   105 (Geosciences): 5% Keywords boundary layer   multi-scale observationr   MMS mission   kinetic simulation   space plasma   energy transfer  
Zusammenfassung  
Der Bereich außerhalb der Erdatmosphäre ist im Großen und Ganzen durch ionisiertes Gas, sogenanntes Plasma, erfüllt. Meist ist die Dichte dieses Weltraum-Plasmas gering genug um die Viskosität zu vernachlässigen, d.h. Stöße zwischen den ionisierten Teilchen sind untergeordnet. Damit ergibt sich ein wesentlicher Unterschied zu neutralen, viskosen Flüssigkeiten, z.B. zu Luft oder Wasser. In solch einem stoßfreien Plasma-System spielen die Grenzschichten zwischen Regionen mit unterschiedlichen Plasmaeigenschaften eine zentrale Rolle für den Energieübertrag und die Dynamik des Systems ganz generell. Ziel dieses Projektes ist das Verstehen des Energietransfers über Grenzschichten des stoßfreien Plasmas hinweg. Diese fundamental wichtige Fragestellung der Weltraumplasmaphysik wurde in der Vergangenheit bereits von einigen Studien adressiert, allerdings blieben quantitative Aspekte des realitätsnahen Energie-Transferprozesses großteils unverstanden. Der Grund dafür liegt im weiten Umfang räumlicher und zeitlicher Skalen, auf denen Energietransfers in stoßfreien Plasmen stattfinden, beginnend mit der kinetischen Skala (Betrachtung von Einzelteilchen) bis hin zur globalen Beschreibung des Systems. Der Umfang der Skalen kann durch Labor- und Satelliten-Messungen allein nicht abgedeckt werden. Aktuelle Fortschritte bei numerischen Simulationen ermöglichen quantitativ umfangreichere Abschätzungen der Transferprozesse, allerdings bleiben bis dato einige unrealistische Annahmen bestehen. Vor diesem Hintergrund ist der wissenschaftliche Fokus dieses Projektes die Quantifizierung des Energietransfer-Prozesses in genauerer Weise als bisher; die Berücksichtigung aller notwendigen Skalen erfolgt durch Plasma-Simulationen auf dem neuesten Stand der Technik, kombiniert mit Plasmamessungen durch in-situ und Fernerkundungs-Methoden. Die Einzigartigkeit des Projektes liegt in der Betrachtung unterschiedlicher Typen von Plasma-Grenzschichten der Erdmagnetosphäre (jener Bereich des Weltraums, in dem das terrestrische Magnetfeld der dominierende Faktor ist). Damit können unterschiedliche Faktoren und Skalen des Energie-Transferprozesses über Grenzschichten hinweg abgedeckt werden – die Erdmagnetosphäre fungiert hierbei als großes Experiment zur Erkundung der Physik von Grenzschichten. Speziell für dieses Projekt wird eine Reihe von umfangreichen Plasma-Teilchensimulationen repräsentativer Grenzschichten der Magnetosphäre durchgeführt. Verwendet wird dafür einer der weltgrößten Supercomputer – „MareNostrum“ – unter Berücksichtigung realistischer Simulationsbedingungen wie sie von hochaufgelösten in-situ Messungen der aktuellen Magnetospheric Multiscale (MMS) Satellitenmission vorliegen. Die Simulationsresultate werden mit den MMS Messungen, mit umfangreichen Datensätzen anderer Satellitenmissionen und mit Bodenbeobachtungen verglichen. Das erlaubt sowohl die lokale Betrachtung der Physik an Grenzschichten als auch die globale Kopplung dieser lokalen Prozesse. Basierend auf den Projektresultaten ergibt sich nicht nur ein quantitatives Verständnis der Physik von Grenzschichten der Magnetosphäre auf verschiedenen Skalen, sondern erstmals auch eine umfangreiche, systematische Sichtweise auf die Physik von Grenzschichten in stoßfreien Plasmen generell. Diese neuen Erkenntnisse erlauben die Anwendung auf zahlreiche weitere planetare und astrophysikalische Objekte und unterstützen somit zukünftige Weltraummissionen.  
Weltraumschrott  
Der zunehmende Weltraumschrott stellt in der heutigen Zeit eine immer größer werdende Gefahr für aktive Satelliten dar. Neben derzeit ca. 1000 aktiven Satelliten und mehr als 1000 alten, nicht mehr aktiven Satelliten befinden sich ca. 40000 mit Radar vermessene und mehr als 500000 Teile (Durchmesser <1 cm) in einer Umlaufbahn um unseren Planeten. Diese Schrottteilchen sind hauptsächlich  Oberstufen von alten Raketen, Teile von explodierenden Satelliten (verursacht durch alternde Akkumulatoren oder Treibstoffreste) oder Trümmer von Kollisionen. Je nach Abstand des Satelliten von der Erde können diese Teile sehr lang in einer Umlaufbahn verbleiben. Während zum Beispiel eine alte Raketenstufe in einer Höhe von 1000 km "schon" nach wenigen tausend Jahren in der Atmosphäre verglüht, wird ein alter Satellit in einem 6000-km-Orbit für die nächsten Millionen Jahre die Erde umrunden. Die Grazer SLR-Station hat auf diesem Gebiet eine internationale Vorreiterstellung eingenommen und beschäftigt sich unter anderem mit den nachstehenden wissenschaftlichen Forschungsgebieten. Bei der multistatischen Distanzmessung zu Weltraumschrott sendet die Grazer SLR-Station mit einem 20-Watt-Laser Photonen zu Weltraumschrott. Das ausgesendete Licht wird an diesem Laser diffus reflektiert und über Mitteleuropa verteilt. Die reflektierten Grazer Photonen können nun von anderen Stationen empfangen werden. In einem bislang einzigartigen Experiment sendete Graz mit einem grünen Laser und Wettzell in Deutschland mit einem infraroten Laser zugleich Photonen aus. Die von Graz ausgesendeten Photonen wurden von Graz und Wettzell empfangen, die von Wettzell ausgesendeten Photonen von Wettzell, Graz und Stuttgart. Die Datenanalyse von solchen gemeinsamen (multistatischen) Experimenten ergab eine signifikante Steigerung der Genauigkeit der Orbitvorhersagen von Weltraumschrott. Bei Stare & Chase beobachtet ("stare") ein einfaches und kostengünstiges Kamerasystem mit einem Gesichtsfeld von ca. 10° einen beliebigen Ausschnitt des Nachthimmels. Dabei werden Sterne bis zur 9. Größenordnung dargestellt. Aus dem Sternenhintergrund wird die Richtung der Kamera in Himmelskoordinaten berechnet. Sobald sich ein von der Sonne beleuchteter Weltraumschrott durch das Gesichtsfeld der Kamera bewegt, wird dieser automatisch detektiert und seine Himmelskoordinaten werden bestimmt. Nur aus diesen Richtungsinformationen des Satelliten wird – ohne vorab vorhandenen Orbitvorhersagen – ein Orbit berechnet und damit direkt eine laserbasierte Distanzmessungen gestartet ("chase"). Der gesamte Prozess von der erstmaligen optischen Erfassung bis zur erfolgreichen Entfernungsmessung kann innerhalb weniger Minuten erfolgen. Für die Bestimmung der Umdrehungsdauer und Drehachse von Weltraumschrott werden Lasermessungen und Lichtkurven miteinander kombiniert. Bei bekannter Geometrie der Retroreflektoren am Satelliten lassen sich aus den Laserdistanzmessungen genaue Informationen zu Spin und Drehachse ermitteln. Der Umweltsatellit Envisat besitzt beispielsweise eine Pyramide mit insgesamt 8 Retroreflektoren. Durch die Rotation des Satelliten nähern und entfernen sich die einzelnen Reflektoren periodisch. Aus diesen Entfernungsvariationen kann man Rückschlüsse auf die Orientierung und Umdrehungsdauer ziehen. Simultan zur Laserdistanzmessung im grünen Bereich des Spektrums wird das vom Satellit reflektierte Sonnenlicht genützt, um sogenannte Lichtkurven aufzunehmen. Diese spiegeln den Helligkeitsverlauf des Satelliten in Abhängigkeit von einer vollständigen Umdrehung (Phase) um die eigene Achse wider. Man kann dabei deutlich die Reflexionen von unterschiedlichen Teilen des Satelliten wie z.B. der Solarpaneele oder des zentralen Korpus erkennen.  
Satelliten  
Die vermessenen Satelliten und Objekte können in vier große Gruppen eingeteilt werden: Passive/geodätische Satelliten Satelliten im nahen Erdorbit Navigationssatelliten Weltraumschrott Passive/geodätische Satelliten sind kugelförmig und ihre Bahn um die Erde wird primär von der Gravitation der Erde und nur wenig von anderen äußeren Kräften beeinflusst. Eine meist große Anzahl an Retroreflektoren liefert ein eindeutig identifizierbares Antwortsignal für diese Entfernungsmessungen. Die Entfernungen reichen dabei von ca. 800 km bis 20.000 km. Der Haupteinsatzbereich für solche Satelliten sind hochpräzise Erdschwerefeldmessungen. Forschungssatelliten im nahen Erdorbit befinden sich in Entfernungen von ca. 450-1.350 km. Ihr Einsatzbereich ist vielschichtig und reicht von der Berechnung von Eismassenvolumen über hochauflösende Radarbilder bis hin Messungen der Meeresströmungen. Wesentlich für diese Satelliten ist die genaue Vermessung ihres Orbits, wie sie durch Lasermessungen erfolgen kann. Neben den bekannten amerikanischen und europäischen Satellitensystemen (GPS und Galileo) besitzen auch China, Russland und Indien eigene Navigationssatelliten. Die Entfernungen zur Erde variieren zwischen 20.000 und 36.000 km, bei Massen zwischen 600 und 1.400 kg. Sie dienen unter anderem der genauen Positionsbestimmung und Navigation auf der Erde.  
Diplomarbeiten & Dissertationen  
Doctoral Thesis Doctoral Thesis Doctoral Thesis Doctoral Thesis Doctoral Thesis Doctoral Thesis Doctoral Thesis Doctoral Thesis Diploma Thesis Diploma Thesis Diploma Thesis Diploma Thesis Diploma Thesis Diploma Thesis Diploma Thesis Diploma Thesis Doctoral Thesis Doctoral Thesis Diploma Thesis Diploma Thesis  
Weltraumwetter  
The science of space weather is concerned with understanding the causes and effects of varying conditions in mainly the Earth's magnetosphere and atmosphere that are mostly driven by the Sun. The solar wind is a supersonic flow of an extremely fast and tenuous plasma that is expelled by the Sun at all times, and interacts with other solar system objects such as planets, comets and asteroids. It carries a magnetic field that is shaped like a spiral due to the rotation of the Sun. Normally, the so-called slow solar wind, which nevertheless impacts Earth with 400 kilometres per second, flows quietly around the Earth's magnetic field. However, during time intervals of strong southward magnetic fields and higher solar wind speeds, which are caused by solar storms (known as coronal mass ejections) and fast solar wind streams, energy is transferred into the magnetosphere and the magnetic field of the Earth is temporarily disturbed. The prediction of the solar wind impacting the Earth's magnetic field is a major unsolved problem in space science. An accurate solar wind forecast would tell us where and when the aurora lights up the sky, or whether power grids in countries at high latitudes such as Canada or Norway are at risks of failure. IWF is working on solar wind predictions for high-speed streams and coronal mass ejections, with numerical, analytical and empirical models. Particularly the runtime of the models is optimized, so that  ensemble simulations with variations in the input parameters can be produced in order to estimate error bars in the predictions, and to make it possible to apply the models in real-time. The team members combine observations from as many spacecraft as possible, including Solar Orbiter and BepiColombo, in order to gain a complete picture of how solar storms and high speed solar wind streams propagate from the Sun to the planets. To this end we are working on a complete Sun-to-Earth chain of our self-developed models, covering the background solar wind and solar storms to predict the solar wind near Earth. Then it is calculated how the errors in the solar wind prediction affect the forecasts of geomagnetic indices, ground-induced currents and the aurora location.  
S/C-Plasma-Wechselwirkung  
Satelliten sind immer von geladenen Teilchen, Ionen und Elektronen, umgeben, die ein sogenanntes Plasma bilden. In einem solchen Plasma laden sich Satelliten vor allem durch die Aufsammlung und Aussendung von Elektronen elektrisch auf. Die Aussendung der Elektronen erfolgt dabei durch den photoelektrischen Effekt, bei dem Elektronen durch ultraviolette Sonnenstrahlung von den Satellitenoberflächen losgelöst werden. Der Umgebungselektronen-Strom zum Satelliten hin, der Photoelektronen-Strom von Satelliten weg, sowie eine Reihe weiterer, unbedeutenderer elektrischer Ströme bestimmt letztendlich das elektrische Potenzial des Satelliten. Das Satellitenpotenzial kann eine nützliche Größe für wissenschaftliche Analysen sein. Unter gewissen Voraussetzungen kann man aus dem Potenzial die Schwankungen der Plasmadichte mit viel höherer zeitlicher Auflösung bestimmen, als dies mit Partikeldetektoren möglich wäre. Dadurch wird die Messung hochfrequenter Dichteschwankungen möglich, die für die Untersuchung turbulenter Fluktuationen im Sonnenwind nützlich sind. Andererseits kann ein hohes Satellitenpotenzial auch unerwünschte Auswirkungen haben. Es können dabei elektrische Entladungen auftreten, die ein Risiko für die Instrumentierung darstellen. Außerdem werden Ionen gleicher Ladung vom Satelliten abgestoßen, so dass sie von Partikeldetektoren nicht mehr beobachtet werden können. Um diesen Auswirkungen entgegenzuwirken, kann das Potenzial durch das Active Spacecraft Potential Control Instrument (ASPOC) aktiv gesteuert werden. Dieses Instrument kann einen Strom positiver Indiumionen vom Satelliten in den Weltraum schießen, wodurch das Satellitenpotenzial verringert wird. Dabei wird die unmittelbare Plasmaumgebung des Satelliten ebenfalls beeinflusst. ASPOC wurde am IWF entwickelt und ist auf den Satelliten der Missionen Double Star, Cluster und zuletzt Magnetospheric MultiScale (MMS) zum Einsatz gekommen. Wissenschaftliche Mitglieder der IWF-Forschungsgruppe "Weltraumplasmaphysik" befassen sich mit der Analyse von Satellitenpotenzialdaten, um daraus genauere Schätzungen der Plasmadichte zu erhalten und um besser zu verstehen, wie sich das Potenzial selbst und die Funktion des ASPOC-Instruments auf die unmittelbare Plasmaumgebung eines Satelliten auswirken.  
Plasma-Simulationen  
Space between planets, stars, and galaxies is commonly filled with plasma with its temperature and density, respectively, high and small enough to neglect Coulomb collisions. Recent in-situ and remote observations have also revealed the existence of space dust in our solar system. The behavior of these space plasma and dust is rather complex and affected by many factors such as the electromagnetic forces, multi-scale waves and instabilities, the charge state and orbital distribution of dust. Mathematical, analytical and numerical modeling and simulations are useful to effectively handle these factors and systematically understand such complex behavior of plasma and dust over a wide range of parameters. Based on various methods of modeling and simulations, members of space plasma physics group are actively working on various research targets in space near the Earth, in the vicinity of other planets, comets and asteroids, near the solar surface, in the solar corona, and in the solar wind. In particular, recent advances in computer resources and numerical techniques enable us to handle large-scale plasma kinetic and magnetohydrodynamic (MHD) simulations of various fundamental plasma phenomena such as magnetic reconnection and plasma turbulence covering a broad range of spatiotemporal scales that cannot be handled only from observations. Working with these simulations lead to a constant development of new mathematical methods and models that are of interest also for other research fields in space science. Comparison between these state-of-the-art modeling/simulations and observations also enable to obtain quantitative understanding of the multi-scale physics of these space plasma and dust phenomena.  
ULF-Wellen  
ULF-Wellen (Ultra-Low Frequency, ULF) haben eine Periode zwischen etwa 1 und 1000 Sekunden. Sie werden mit Magnetometern sowohl auf der Erde als auch im Weltraum gemessen. Man findet sie nicht nur im erdnahen Weltraum, sondern auch um andere Planeten und im interplanetaren Raum. Die ULF-Wellenforschung begann 1859, als B. Steward am Kew Observatory einen magnetischen Sturm beobachtete. In den frühen Jahren konnten ULF-Wellen nur mit Bodenmagnetometern gemessen werden. So ließ sich zwar die Quelle dieser globalen magnetischen Oszillationen nicht herausfinden, aber man konnte sie katalogisieren. Man fand heraus, dass manche quasi-sinusoidal und kontinuierlich waren (continuous Pulsations, Pc), während andere unregelmäßige Frequenzen hatten und irreguläre Pulsationen (irregular Pulsations, Pi) genannt wurden. Diese Wellen sind stehende oder fortschreitende Oszillationen des (Erd)Magnetfeldes. Auf den geschlossenen Dipolfeldlinien können sich (harmonische) stehende Wellen bilden, ähnlich den Oszillationen einer Geigensaite. Diese Wellen werden Feldlinienresonanzen genannt, die in die Kategorie Pc-5 fallen. Ihre Frequenz kann z.B. für die Abschätzung der Ionenmassedichte am magnetischen Äquator verwendet werden. Im Weltraumzeitalter wurden in-situ Messungen gemacht, mit denen die Quelle und/oder Eigenschaften der Wellen bestimmt werden konnten. Man erkannte aber schon in den späten 1970er Jahren, dass man mehrere Satelliten benötigt, um vernünftige Messungen zu machen. Deshalb wurden 1977 ISEE 1 und 2 gestartet. Im Magnetschweif können ULF-Wellen durch explosive Ereignisse wie magnetische Rekonnexion erzeugt werden. Durch die spezielle Geometrie des Schweifs, werden verschiedene Eigenmode wie z.B. Magnetotail Flapping erzeugt. Andererseits kann durch den schnellen Plasmafluss eine Instabilität auf der Seite des Flusskanals entstehen und die Kelvin-Helmholtz-Instabilität kann ULF-Wellen erzeugen. Solche Wellen können mit Multi-Satelliten-Missionen wie Cluster, THEMIS und MMS sehr gut erforscht werden. Mit Mehr-Punkt-Messungen lassen sich Charakteristika wie Fortpflanzungsgeschwindigkeit und räumliche und zeitliche Entwicklung dieser ULF-Wellen gut bestimmen. ULF-Wellen gibt es nicht nur in der Erdmagnetosphäre, sondern auch an anderen Orten im Sonnensystem. Leider gibt es bei diesen Beobachtungen meistens nur Daten eines einzelnen Satelliten. Venus Express hat im Orbit um die Venus Ion-Zyklotron-Wellen (Pc-5) gemessen. Obwohl die Venus kein eigenes Magnetfeld hat, können diese Wellen im Sonnenwind rund um den Planeten erzeugt werden, indem Ionen durch Ionisierung von neutralen Teilchen aus der erweiterten Exosphäre kreiert werden. Ein spezieller Fall war die Beobachtung des singenden Komets. Rosetta hat Wellen mit einer Frequenz zwischen 40 und 100 mHz rund um den Kometen 67P/Churyumov-Gerasimenko gemessen. Diese Wellen wurden durch ein bislang unbeobachtetes Phänomen erzeugt. Weil der Gyroradius der neu kreierten Ionen sehr groß war, wurden die Magnetfeldlinien rund um den Kometen wie die Saiten einer Geige zum Schwingen gebracht. Während der Landung von Philae, auch mit einem Magnetometer ausgestattet, gab es für kurze Zeit 2-Punkt-Messungen. Die ESA-Mission zum Merkur, BepiColombo, wird die hermetische Magnetosphäre untersuchen, die sehr dynamisch ist. Frühere Missionen haben gezeigt, dass es bei Merkur starke ULF-Wellenaktivität durch Rekonnexion gibt, aber auch Zyklotronwellen durch die Erzeugung von Ionen im Sonnenwind. Hier werden die beiden Raumsonden MMO und MPO 2-Punkt-Messungen der Magnetosphäre machen. Die zukünftige Jupiter-Raumsonde der ESA, JUICE, wird ULF-Wellen in Jupiters riesiger Magnetosphäre erforschen. Am Ende der Mission wird JUICE in eine Umlaufbahn um Ganymed gebracht und dessen kleine Magnetosphäre untersuchen, von der man weiß, dass es Feldlinienresonanzen gibt.  
Plasmaturbulenz  
Turbulence results from multi-scale nonlinear interactions and from instabilities of large-scale fluid motions involving many degrees of freedom. Collisionless space plasmas such as the solar wind or plasmas in planetary environments are in a turbulent non-equilibrium state, characterized by strong fluctuations of field and plasma parameters over multiple scales.  The fluctuations are present from the largest energy injection scales through  magnetohydrodynamic or fluid scales, where friction forces are negligible, to the smallest dissipation scales where the available energy is converted to heat. In the absence of collisions physical processes become increasingly more complex near the ion/electron kinetic scales. Near and over the kinetic scales the energy transfer/exchange between the electromagnetic fields, plasma motions and particles is possible via various channels of dynamics. Physical constraints in plasma turbulence lead to the generation of coherent intermittent structures such as (reconnecting) current sheets, vortices, discontinuities or flux tubes. Although plasma turbulence is considered to be highly nonlinear, it is often hypothesized that linear physics remains important for the turbulence dynamics and the system may retain some properties of linear wave modes. However, over the kinetic scales the waves become dispersive and dissipative also exhibiting anisotropies with respect to the mean magnetic field. Particularly interesting questions which has to be addressed in near ion or sub-ion scale space plasma turbulence are: (a) What kind of wave modes (co-)exist under different plasma conditions? (b) What kinds of intermittent spatial structures do the turbulent motions and fields exhibit? At IWF both theoretical and experimental studies dedicated to space plasma turbulence are carried out. The space missions targeted in these studies are the multi-spacecraft Cluster and MMS missions and inner heliospheric missions such as Solar Orbiter and BepiColombo. Multi-point and single-point wave analysis methods are developed to distinguish between linear wave modes in sub-ion scale compressive or incompressive turbulence such as kinetic slow waves, kinetic Alfven waves or ion-Bernstein magnetosonic waves. In this effort the high resolution electron density obtained and calibrated from the spacecraft potential was very useful. Multi-point Cluster and MMS data are useful to  observe current sheets and understand better energy conversion at kinetic scales in the magnetosheath. Reconnecting small-scale current sheets in turbulent magnetosheath are associated with whistler emissions and lower-hybrid drift waves. The coherent structures can be responsible for turbulence intermittency, however, using the techniques proposed by the group members, it was also shown that the presence of wave activity can potentially reduce intermittency at sub-ion scales. Theoretical investigations help us to understand the observed scalings on spatial scales smaller than the ion inertial length. Hall turbulence appears to be the likely candidate to explain the steepening of the magnetic energy spectra. Analytical calculations based on the linear Vlasov theory allowed to derive the dielectric tensor of plasma containing various fluid picture processes in the lowest order. It is expected that the predicted transport ratios offer a diagnostic tool to study and identify the kinetic Alfven mode in the inner heliosphere for Solar Orbiter data.          Cluster and MMS missions and inner heliospheric missions such as Solar Orbiter and BepiColombo. Multi-point and single-point wave analysis methods are developed to distinguish between linear wave modes in sub-ion scale compressive or incompressive turbulence such as kinetic slow waves, kinetic Alfven waves or ion-Bernstein magnetosonic waves. In this effort the high resolution electron density obtained and calibrated from the spacecraft potential was very useful. Multi-point Cluster and MMS data are useful to  observe current sheets and understand better energy conversion at kinetic scales in the magnetosheath. Reconnecting small-scale current sheets in turbulent magnetosheath are associated with whistler emissions and lower-hybrid drift waves. The coherent structures can be responsible for turbulence intermittency, however, using the techniques proposed by the group members, it was also shown that the presence of wave activity can potentially reduce intermittency at sub-ion scales. Theoretical investigations help us to understand the observed scalings on spatial scales smaller than the ion inertial length. Hall turbulence appears to be the likely candidate to explain the steepening of the magnetic energy spectra. Analytical calculations based on the linear Vlasov theory allowed to derive the dielectric tensor of plasma containing various fluid picture processes in the lowest order. It is expected that the predicted transport ratios offer a diagnostic tool to study and identify the kinetic Alfven mode in the inner heliosphere for Solar Orbiter data.  
Magnetische Rekonnexion  
Einer der wichtigsten Energieumwandlungsprozesse in der Weltraumplasmaphysik ist die sogenannte magnetische Rekonnexion. Dabei ändert sich die Topologie des Magnetfeldes abrupt in einem räumlich begrenzten Bereich. Dies führt zu einer Beschleunigung und Erwärmung der geladenen Teilchen in der Umgebung, wodurch magnetische in kinetische Energie umgewandelt wird. Es ist besonders wichtig dieses Phänomen besser zu verstehen, da dieser lokale Prozess Plasmatransporte auf globaler Ebene antreiben und spontan große Energiemengen freisetzen kann. Der Weltraum stellt ein natürliches Plasmalabor dar und ist daher optimal geeignet um physikalische Phänomene wie die magnetische Rekonnexion anhand von Satellitenmessungen zu untersuchen. Während ein Satellit das Plasma und Magnetfeld lokal messen kann, kann man mit Hilfe von Simultanmessungen mehrerer Satelliten zeitliche und räumliche Variationen in den Messdaten voneinander trennen. Damit wird es möglich, den komplexen Energieumwandlungsprozess der magnetischen Rekonnexion im Detail zu untersuchen und besser zu verstehen. Die Forschungsgruppe "Weltraumplasmaphysik" arbeitet aktiv an der Datenanalyse von Multi-Satellitenmissionen wie  Cluster, THEMIS und MMS und vergleicht deren Messergebnisse mit fortschrittlichen Computersimulationen, um die magnetische Rekonnexion von der kleinskaligen Teilchenphysik bis hin zu deren großräumigen Auswirkungen im erdnahen Weltraum genauer zu erforschen.  
Sonnenwind & Magnetosphären  
Die Sonne emittiert ständig geladene Teilchen, die das Magnetfeld der Sonnenkorona bis zum Rand unseres Sonnensystems tragen. Obwohl dieser sogenannte Sonnenwind immer vorhanden ist, ist seine Stärke doch variabel, da die Sonne periodisch mehr Teilchen in Phasen stärkerer Sonnenaktivität auswirft. Wenn der Sonnenwind mit Überschallgeschwindigkeit auf Hindernisse im Sonnensystem trifft, z.B. auf Magnetfelder oder Atmosphären geladener Teilchen um Planeten, Monde oder Kometen, so kann er dynamisch Bugstoßwellen vor den Hindernissen bilden und diese umströmen und umschließen – sie werden so zu Magnetosphären. Magnetosphären bilden und entwickeln sich an jedem Objekt des Sonnensystems unterschiedlich, da sie Hindernisse unterschiedlicher Größe und Art darstellen, beispielsweise aufgrund eines (nicht) vorhandenen intrinsischen Magnetfeldes und seiner Stärke. Das IWF-Team interessiert sich für die grundlegende Physik von Gasen geladener Teilchen (Plasmen) und für die Wechselwirkungen zwischen Sonnenwind und den entsprechenden Magnetosphären. Das sind zum Beispiel der Transport von Plasma und magnetischem Fluss im magnetosphärischen Schweif, die Wechselwirkung von Stoßwellen-reflektierten Teilchen mit dem Sonnenwind, die Wellenausbreitung und Verstärkung an magnetosphärischen Grenzschichten oder in der Magnetosphäre selbst, bzw. die Beziehungen zwischen diesen und anderen Phänomenen. Um die Wechselwirkungen zwischen dem Sonnenwind und den Magnetosphären (der Erde, anderer Planeten und Kometen) zu untersuchen, sind in-situ Beobachtungen in den Wechselwirkungsumgebungen, vor allem aber in unterschiedlichen Regionen der Magnetosphären, notwendig. Mitglieder der Gruppe Weltraumplasmaphysik sind aktiv an der Analyse von in-situ Daten verschiedener Satellitenmissionen beteiligt, z.B. Cluster, THEMIS, MMS und Rosetta. Sie bereiten ebenfalls Messungen bei Merkur (BepiColombo, 2018 gestartet) vor und werden an zukünftigen Missionen zum Mars (Tianwen-1) und zu einem Kometen oder extrasolarem Objekt (Comet Interceptor) teilnehmen. Eine neue Art der Fernerkundung der äußeren magnetosphärischen Grenzschicht der Erde und der Polarlichter wird durch die Mission SMILE in Zukunft möglich sein.  
Ionosphären-Dynamo  
In diesem Forschungsbereich charakterisieren und untersuchen wir Prozesse, die elektrische Felder und Ströme in den elektrisch leitenden Schichten der Ionosphäre erzeugen. Diese Felder und Stöme interagieren in höheren Lagen mit der Magnetosphäre und in niedrigeren Lagen mit der Atmosphäre. Dieser Atmosphärenbereich kann aufgrund der Beziehung zum erdnahen Weltraum über die Magnetosphäre und die Lithosphäre der Erde als Schlüsselregion angesehen werden. Am IWF verwenden wir zwei Ansätze, welche die Fernerkundung von Plasma in den ionosphärischen Schichten ermöglichen. Der eine basiert auf der Modellierung von Stömungen im Ionosphären-Dynamo, der andere auf der Anwendung von Funkwellenausbreitungen. Die Kombination beider Methoden ermöglicht es uns, unsere Modelle zu optimieren und beobachtete Werte mit den berechneten elektrischen Feldern und magnetischen Variationen zu vergleichen. Die Atmosphäre, Ionosphäre und Magnetosphäre stehen miteinander in Verbindung, wobei die Einflüsse der Sonnenaktivität auf magnetische, Plasma- und neutrale Komponenten der Erdumgebung untersucht werden. Die Modellierung der physikalischen Parameter der Ionosphäre wird dabei mit den beobachteten magnetischen Bodenstörungen auf Übereinstimmungen verglichen. Die Abbildung (zum Vergrößern klicken) zeigt eine schematische Darstellung der Untersuchungen des Ionosphären-Dynamos auf der Grundlage von: (a) Gesammelten Beobachtungen, die von Raumfahrzeugen (CSES, DEMETER, SWARM und WIND) und bodengestützten ULF- und VLF/LF-Stationen (INFREP, INTERMAGNET) aufgezeichnet wurden, (b) der Verwendung von Magnetfeldmodellen und Leitfähigkeiten als Eingabeparameter für die dynamische Simulation der Ionosphäre und (c) der Kombination vom berechneten elektrischen Feld und magnetischen Variationen mit solaren und geomagnetischen Aktivitätsindizes, die aus Weltraum- und Bodenbeobachtungen abgeleitet wurden. Kürzlich haben wir die Ausbreitung seismogener elektrischer Ströme durch die Erdatmosphäre analysiert, wobei solche Ströme mit der Erdbebenzone in der Lithosphäre verbunden sind. Auch subionosphärische VLF/LF-Sendersignale werden verwendet, um die Dynamik der D- und E-Schichten in der Ionosphäre unter dem Einfluss der solaren und geomagnetischen Aktivitäten hervorzuheben. Die Ausbreitung elektomagnetischer VLF/LF-Wellen lässt uns auf das Funkspektrum zwischen dem Boden und der unteren Ionosphäre schließen.  
Extraterrestrische Oberflächen  
In space science the solid surface of objects in our solar system have attracted much interest over the last decades. IWF dedicates its research to understand the evolution of the surface and the near subsurface regions of planets, moons and comets. The focus is laid in particular on the individual physical processes that go on at and below the surface of these solid bodies. Investigations apply to optical and electrical properties, as well as the thermal evolution, the heat balance, and the gas diffusion through the near-surface material. By studying the involved physical processes IWF also contributes to the understanding of the consequences for the atmosphere-surface interaction and so the influence on the atmosphere evolution. The investigations have always involved international cooperation in connection with space missions where hardware contributions (Rosetta/Philae) or data modelling and interpretation (Cassini/Huygens, InSight) played an essential role. Observations have shown that the interpretation of many measurements is difficult because of the complex interconnection of the involved physical processes. Therefore, it is essential to study certain processes in an isolated way. This is achieved, on the one hand, by experimental investigations with suitable analogue materials, and on the other hand, by analytical models and numerical computer simulations. Currently all these methods are applied in the DACH project CoPhyLab (Cometary Physics Laboratory), with emphasis on laboratory measurements.  
Atmosphären-Evolution  
In diesem Forschungsbereich konzentrieren wir uns auf die Wechselwirkungsprozesse von solarer oder stellarer Strahlung und Plasma mit den oberen Atmosphären von Planeten und Körpern ohne Atmosphären (z.B. Merkur, Mond/e, Kometen, Asteroiden und planetare Embryos). Die Entwicklung der Planetenatmosphären von primordialen Atmosphären, mit Magma-Ozeanen in Verbindung stehenden Dampfatmosphären und Sekundäratmosphären werden untersucht. Der Ursprung und das Entweichen von Exosphären aus planetaren Körpern ohne Atmosphären sowie die Auswirkungen auf deren Änderung der Oberflächenzusammensetzung werden ebenfalls untersucht. Variationen von Isotopen und flüchtigen Elementen in verschiedenen Planetenreservoirs geben Auskunft über das Entweichen einer Atmosphäre, die Zusammensetzung und sogar die Quelle des akkretierenden Materials. Zur Untersuchung der Evolutionsprozesse werden bekannte atmosphärische Isotopen- und Elementverhältnisse für evolutionäre Reproduktionsversuche verwendet. Der Ursprung der N2-O2-dominierten Sekundäratmosphäre der Erde wird im Rahmen einer vergleichenden Planetologie zwischen Venus, Mars und potenziellen terrestrischen Exoplaneten untersucht. Ein besseres Wissen darüber, wie die Erde ihre Biosphäre hervorgebracht hat, wird dann auch unser Verständnis im Hinblick auf die potenzielle Bewohnbarkeit von erdähnlichen Exoplaneten verbessern. Abbildung a) zeigt die wahrscheinlichsten Proto-Erd-Akkretionsszenarien, die durch unterschiedliche Isotopensystematik (D-H, atmosphärisches Ar & Ne, ursprüngliche 3He-Häufigkeit im tiefen Mantel) und Isotopen-Chronometer (Hf-W, UP) in Abhängigkeit von der Lebensdauer und Aktivität der jungen Sonne durch das IWF-Team aus mehreren ihrer veröffentlichten Forschungsartikeln abgeleitet werden können. Der Massenanteil von Proto-Earth während der Scheibenverteilung sollte danach etwa 0,5 - 0,6 MEarth (dunkelgrauer Bereich) betragen haben. Abbildung b) zeigt die modellierten Reaktionen der oberen Atmosphäre auf die von N2-O2 dominierte Erdatmosphäre im Vergleich zu Saturns großem Mond Titan, einem Körper im äußeren Sonnensystem mit einer N2-Atmosphäre. Die Erdatmosphäre wäre in den ersten mehreren hundert Millionen Jahren nicht stabil gegen die höhere weiche Röntgenstrahlung und der extremen ultravioletten Strahlung (XUV) der jungen Sonne gewesen, was darauf hinweist, dass ihre Atmosphäre höchstwahrscheinlich eine andere Zusammensetzung hatte, und sehr wahrscheinlich CO2-dominant war.  
SLR-Station  
Die Grazer SLR-Station ist eine der führenden Laserstationen weltweit. Ihr Herzstück ist ein Nd:Vanadate kHz Laser System. Dieses generiert 2000 kurze Laserpulse in der Sekunde, das entspricht einer Frequenz von 2 kHz. Die Dauer eines einzelnen Laserpulses beträgt nur 10 Pikosekunden.  Zum Vergleich: Licht legt mit einer Geschwindigkeit von 300000 km/s in dieser kurzen Zeit eine Strecke von ca. 3 mm zurück. Ein einzelner Puls hat dabei eine Energie von 400 µJ, das entspricht ca. einer Million mal einer Milliarde Photonen. Am Satelliten reflektieren Retroreflektoren einen kleinen Teil des Lichtpulses wieder zur SLR-Station zurück. Einige wenige Photonen (in den meisten Fällen nur ein einziges Photon) werden von einem 0,5 m-Teleskop aufgefangen und von einem Einzel-Photon-Detektor registriert. Dieser Detektor hat einen Durchmesser von etwa 200 µm (etwa 4-mal so viel wie ein menschliches Haar). Je nach Entfernung des Satelliten benötigen die Photonen dafür nur einige Millisekunden bis etwa 0,25 Sekunden. Eine für kHz-SLR-Systeme optimierte Echtzeit-Software wurde vom Grazer SLR-Team entwickelt und kann daher sehr flexibel eingesetzt und erweitert werden. Ein Grafikinterface ermöglicht auch ungeübten Anwendern eine leichte Bedienung. Nach nur einer Trainingsnacht können auch unerfahrene Beobachter die SLR-Station bereits ohne größere Probleme bedienen. Die Echtzeit-Software beinhaltet bereits eine beachtliche Menge von Automatiken: Automatische Erkennung potentieller Returns im Hintergrundrauschen NUR diese werden gespeichert, um die Größe der Files zu reduzieren Automatisches Setzen / Anpassen / Optimieren des Range-Gates Automatisches Berechnen und Setzen von Time Bias-Werten Automatisches Optimieren der Nachführung Erkennung von unerwünschten Pre-Pulsen, Reduzierung durch Offset-Pointing Automatische Suchroutinen, um den Satelliten zu finden Zusätzlich zur Beobachtungssoftware kommen einige weitere Softwaretools zum Einsatz. Mittels einer speziellen Kamera kann die Rückstreuung des Laserlichts in der Atmosphäre auch bei Tag beobachtet werden. Dies erleichtert den Beobachtern die Einstellung der Richtung des Laserstrahls. Nachts können von der Sonne beleuchtete Satelliten mittels einer hochempfindlichen astronomischen Kamera auch optisch sichtbar gemacht werden. Das Messen mit 2 kHz, mit relativ schwacher Energie pro Puls und mit Single-Photon-Detektor ergibt – speziell bei hohen Satelliten – sehr niedrige Return-Raten mit einem sehr hohen Rauschanteil (geringes Signal/Rauschverhältnis). Bei GPS-Satelliten beträgt die durchschnittliche Return-Rate etwa 0,001. Das bedeutet, dass bei 2000 Schüssen pro Sekunde durchschnittlich nur etwa 2 Returns empfangen werden, die in unter 1998 Rauschpunkten versteckt sind. Die Echtzeit-Return-Erkennung muss diese zwei potentiellen Returns erkennen, abspeichern und das Rauschen verlässlich ausscheiden.  
Testanlagen  
Bevor Fluginstrumente in den Weltraum geschickt werden, müssen diese im Vakuum und in verschiedenen Temperaturbereichen getestet werden. Ein spezielles Magnetometerlabor steht für die Kalibrierung der Sensoren zur Verfügung. Das IWF besitzt vier verschiedene Arten von Vakuumkammern. Die kleinste ist eine manuell gesteuerte, zylindrische Vakuumkammer (160 mm Durchmesser, 300 mm Länge) für kleine elektronische Bauteile oder Leiterplatten. Sie verfügt über eine Turbomolekularpumpe und eine Dryscroll-Vorpumpe. Es kann ein Druckniveau von 10-10 mbar erreicht werden. Die mittlere Vakuumkammer hat einen zylindrischen Edelstahlkörper mit einer Gesamtlänge von 850 mm und einem Durchmesser von 700 mm. Eine Dryscroll-Vorpumpe und zwei Turbomolekularpumpen sorgen für ein Druckniveau von etwa 10-7 mbar. Ein Manipulator mit drei orthogonalen Drehachsen für die individuelle Ausrichtung des zu testenden Messinstruments und eine Ionenstrahlquelle sind installiert. Diese Kammer dient hauptsächlich für Funktionstests des Ionen-Massenspektrometers für BepiColombo. Die größte Vakuumkammer hat einen horizontalen zylindrischen Körper aus Edelstahl, ein Sichtfenster, zwei Turbomolekularpumpen und eine Dryscroll-Vorpumpe. Es kann ein Druck von 10-7 mbar erreicht werden. Der Zylinder hat einen Durchmesser von 650 mm und eine Länge von 1650 mm. Beim Abschalten der Kammer wird diese automatisch mit Stickstoff geflutet. Ein Manipulator innerhalb der Kammer ermöglicht die computergesteuerte Rotation eines Instruments um drei voneinander unabhängige, senkrechte Achsen. In der Kammer ist eine magnetische Abschirmung aus Mu-Metall mit einem Querschnitt von 200 mm x 200 mm installiert. Zum Ausheizen elektronischer Komponenten und Strukturen - d.h. Ausgasen flüchtiger Produkte, um unerwünschte Kontaminationen zu verhindern - ist die Kammer an der Außenseite mit einer Heizung ausgestattet. Die Thermal-Vakuumkammer ist mit zwei Turbomolekularpumpen, einer Dryscroll-Vorpumpe und einer Ionengetterpumpe ausgestattet, die zusammen ein Druckniveau von 10-6 mbar erreichen. Eine in der Kammer installierte Heiz-Kühlplatte sowie ein Heiz-Kühlzylinder und flüssiger Stickstoff werden für Wärmezyklen in einem Temperaturbereich zwischen -160 °C und +140 °C verwendet. Die vertikal ausgerichtete zylindrische Kammer erlaubt einen maximalen Versuchsdurchmesser von 410 mm und eine maximale Höhe von 320 mm. Für Temperaturprüfungen unter Umgebungsdruck stehen zwei Thermalkammern zur Verfügung. In einer Kammer kann die Widerstandsfähigkeit elektronischer Komponenten und Schaltungen bei Temperaturen von -40 °C bis +180 °C verifiziert werden. Sie hat einen Prüfraum von 190 Litern und ist mit einem 32-Bit-Steuer- und Kommunikationssystem ausgestattet. Die zweite, deutlich kleinere Kammer wird insbesondere für rasche Thermalzyklen eingesetzt, wie sie zur Qualifikation von elektronische Komponenten und Prozessen notwendig sind. Der Temperaturbereich beträgt -70 °C bis +180 °C. Diese Kammer hat einen Prüfraum von 37 Litern und ist mit mehreren Schnittstellen für die Kommunikation ausgestattet. Im Magnetometerlabor werden zwei dreischichtige magnetische Abschirmungen aus Mu-Metall für alle grundlegenden Magnetometertests und spezielle Kalibrierprüfungen verwendet. Das verbleibende Gleichfeld im abgeschirmten Volumen beträgt <10 nT und das verbleibende Feldrauschen beträgt <2 pT/√Hz bei 1 Hz. Ein spezielles Helmholtz-Spulensystem ermöglicht die Erzeugung von beliebig ausgerichteten Feldvektoren von bis zu ±30.000 nT, um das Erdmagnetfeld zu kompensieren oder einen Sensor zu kalibrieren. In einer Temperatur-Prüfeinrichtung in Kombination mit einer magnetischen Abschirmung werden die Magnetfeldsensoren im Temperaturbereich zwischen ‑170 °C und +220 °C in einer Umgebung mit geringem DC-Feld und sehr geringem Rauschen getestet. Die Kühlung erfolgt mit flüssigem Stickstoff, wobei die Temperaturregelung eine Genauigkeit von ±0,1 °C erreicht. Während der Testzyklen kann zur Kalibrierung ein Magnetfeld von bis zu ±100.000 nT an den Sensor angelegt werden. Das IWF betreibt auch ein großes dreidimensionales Merritt-Spulensystem in Zusammenarbeit mit der Zentralanstalt für Meteorologie und Geodynamik (ZAMG). Es befindet sich im Conrad-Observatorium in einem Naturschutzgebiet am Rande der Ostalpen, etwa 50 km südwestlich von Wien. Die Abgeschiedenheit des Standortes garantiert eine ungestörte Umgebung für die absolute Kalibrierung von Magnetfeldsensoren. Das Spulensystem hat eine Seitenlänge von etwa drei Metern. Zwei Spulenpaare entlang jeder Achse ermöglichen eine Feldhomogenität von besser als 4x10-5 in einem Testvolumen von 200 x 200 x 200 mm in der Mitte der Spule. Das Spulensystem verfügt über getrennte Spulen für die Kompensation des Erdfeldes und der dynamische Bereich der Hauptspulen beträgt ±100.000 nT.  
Hochleistungsrechner  
Der neue Hochleistungsrechner LEO besteht aus einem Login-Server zur Jobverarbeitung sowie 32 Rechenknoten mit insgesamt 1320 Prozessoren. Für die Software-Bibliothek werden sogenannte "environment module" verwendet, mit denen Benutzer eine bestimmte Software-Version schnell und einfach in ihre Umgebung einbinden können, während andere Benutzer gleichzeitig eine andere Version benötigen. Für die Resultate besonders großer Simulationen stellt ein angeschlossener Daten-Server ca. 150 TB an Festplattenkapazität mit unterschiedlichen Backup-Ebenen zur Verfügung. Die Solid State Drives (SSD) in den Rechenknoten formieren sich zu einem massiv-parallelen BeeGFS-Dateisystem. Besonders wichtig für das Hochleistungs-Rechnen ist auch das 56 GBit/s InfiniBand-Netzwerk mit geringer Latenz im Nanosekunden-Bereich. Eine Dokumentation mit Notfall-Prozeduren erlaubt eine vollständige Neuinstallation des Betriebssystems innerhalb von ca. zwei Stunden. Die Hardware (siehe Abb.) lädt und verarbeitet automatisch die neuesten Daten der MMS-Mission und wird aktiv genutzt, um Simulations-basierte Forschung zu betreiben.  
EDI  
Das Electron Drift Instrument (EDI) vermisst mit zwei Elektronenstrahlen das den Satelliten umgebende elektrische Feld. Insgesamt wurden jeweils zwei gleichartige Instrumente pro Satellit gebaut und geliefert. IWF war für die Entwicklung und den Bau der Digitalelektronik der Detektoreinheit und die Elektronenkanone verantwortlich. RUAG Space Austria entwickelte und baute die gesamte Spannungsversorgung, die unter anderem die für dieses Instrument erforderliche 3000-Volt-Hochspannung liefert. Die Gesamtverantwortung für EDI liegt bei der University of New Hampshire (USA), wo das Instrument vollständig integriert und getestet wurde.  
DFG  
Auf Grund der Neuentwicklung einer hochintegrierten elektronischen Schaltung (Chip) zur Magnetfeldmessung nach dem Fluxgate-Prinzip wurde das Magnetometerlabor des IWF eingeladen, basierend auf dem Chip eine miniaturisierte Sensorelektronik für das Digital FluxGate (DFG) Magnetometer der NASA-Mission MMS zu entwickeln. DFG ist Teil des Instrumentenpakets FIELDS, das von der University of New Hampshire angeführt wird. Der Sensor für das Magnetometer wurde von der University of California, Los Angeles geliefert. Der Chip wurde gemeinsam mit den Fraunhofer Institut für Integrierte Schaltungen entworfen. Der Bau erfolgte bei ams AG unweit von Graz. Die feinsten Strukturen des Chips, der mehr als 50.000 Transistoren enthält, sind nur 0,00035 mm groß. Im Vergleich zu früheren Magnetometern ist es durch die Verwendung dieser hochintegrierten Elektronik gelungen, den Stromverbrauch der Ausleseelektronik um den Faktor zehn zu verringern und die Größe der Elektronik um den Faktor vier zu verkleinern.  
ASPOC  
In Regionen mit geringer Plasmadichte wird ein dem Sonnenlicht ausgesetzter Satellit durch den Austritt von Elektronen positiv (bis zu mehreren 10 Volt) aufgeladen. Das dadurch entstehende elektrische Feld stört die Messdaten der Elektronen- und Ionensensoren und die angezogenen Photoelektronen reduzieren die Lebensdauer der in Elektronensensoren eingebauten Micro-Channel-Plates. Das entstehende Potenzial kann auch die Genauigkeit der elektrischen Feldmessung erheblich beeinflussen. Das Instrument ASPOC neutralisiert das Satellitenpotenzial durch die Freisetzung von positiv geladenen Indium-Ionen. ASPOC wurde unter der Leitung des IWF in Kooperation mit RUAG Space Austria und FOTEC Forschungs- und Technologietransfer GmbH gebaut. Jedes ASPOC-Instrument enthält vier Ionenemitter, wobei immer nur ein Emitter zu einem gegebenen Zeitpunkt aktiv ist. Gegenüber früheren Missionen wurde sowohl das Design der Emitter und der Bordelektronik als auch die Kontrollsoftware verbessert.  
Magnetospheric MultiScale  
Die NASA-Mission Magnetospheric Multiscale (MMS) wurde am 13. März 2015 an Bord einer Atlas V-Trägerrakete von Cape Canaveral, Florida, aus gestartet. Ihr Ziel ist die Untersuchung der Dynamik der Erdmagnetosphäre und der ihr zu Grunde liegenden Energieumwandlungsprozesse. Vier identisch bestückte Satelliten führen seither dreidimensionale Messungen in der Erdmagnetosphäre durch. Die MMS-Satelliten sind ein weiterer Meilenstein nach der sehr erfolgreichen ESA-Mission Cluster: Sie fliegen noch näher zusammen und erforschen in mehreren Phasen unterschiedliche Gebiete des erdnahen Weltraums. Das IWF ist der größte nicht-amerikanische Partner der Mission. Im Mittelpunkt der Untersuchungen steht die magnetische Rekonnexion, bei der magnetische Energie in Teilchenenergie umgewandelt wird, wodurch auf der Erde magnetische Stürme und Phänomene wie das Nordlicht entstehen. MMS soll die verantwortlichen physikalischen Prozesse einschließlich der äußeren Bedingungen und des räumlichen und zeitlichen Verlaufs genauestens vermessen. Man erwartet sich aus den MMS-Daten aber auch weiterreichende Erkenntnisse über die Sonne und ihren Einfluss auf die Erde und das Sonnensystem. Die NASA hat das Southwest Research Institute (SwRI), San Antonio, USA, mit der Leitung der Mission betraut. Jede der Nutzlasten enthält den bisher umfangreichsten Satz an schnellen Teilchen- und Feldmessinstrumenten. Dazu gehört das Instrumentpaket FIELDS zur Messung elektrischer und magnetischer Felder mit jeweils mehreren Sensoren, drei Instrumentpakete für Teilchenmessungen (mit den Schwerpunkten hohe Zeitauflösung, Zusammensetzung und hochenergetische Teilchen) sowie Instrumente zur Regelung des Satellitenpotentials. Das IWF hat die Federführung bei der Potentialregelung der Satelliten (ASPOC) und ist an dem Elektronenstrahlinstrument (EDI) und dem Digital Fluxgate Magnetometer (DFG) beteiligt. Weiterführende Informationen finden Sie bei der NASA und am SwRI.  
RPW  
Das Radiowelleninstrument RPW (Radio and Plasma Waves) ist einzigartig unter den Instrumenten auf Solar Orbiter, da es sowohl In-Situ- als auch Remote-Sensing-Messungen durchführt. RPW misst die magnetischen und elektrischen Felder in hoher zeitlicher Auflösung und mithilfe mehrerer Sensoren und Antennen kann das Instrument die elektromagnetischen und elektrostatischen Wellen im Sonnenwind charakterisieren. Mit den Antennen der Raumsonde kann man Intensität, Polarisation und Einfallsrichtung von Radiowellen genau ermitteln und daraus deren Quellpunkt bestimmen. Diese Messungen liefern aber nur dann exakte Resultate, wenn man die Empfangseigenschaften der Antennen genau kennt. Die Methode der Rheometrie zur Antennenkalibrierung hat am IWF bereits eine lange Tradition, die in den 1990er Jahren mit Cassini begonnen hat. RPW wurde unter der Leitung von LESIA, Observatoire de Paris, Frankreich, entwickelt. Das IWF war für die Antennenkalibrierung verantwortlich und baute den Bordcomputer für RPW.  
Solar Orbiter  
Ziel: Sonne; Start: 2020; Agentur: ESA