Seminar: What do satellite orbits reveal about the thermospheric response to space weather?

Solar activity influences the Earth's atmosphere, increasing atmospheric drag on satellites and reducing thier lifetimes. Using two years of high-resolution orbit data from eleven satellites in Low Earth Orbit (LEO), combined with solar wind and geomagnetic measurements, we address three questions: How do satellites in LEO decay? How fast does the atmosphere around satellites respond to space weather? And can satellite decay rates be predicted continuously? First, decay rates depend strongly on altitude and geomagnetic activity: absolute decay is largest at low altitudes, while background-relative increases during storms are largest at higher altitudes, of up to twelve-fold during the strongest events. Second, atmospheric response times to solar wind disturbances varied widely, from a few hours to about two days. Third, we show decay rates can be predicted from past solar wind and geomagnetic data and infer, for each observable, which points in time yield the strongest contribution to the prediction. We close by outlining current research directions.
Informationen
IWF Seminar series
Speaker
Vanessa Mercea
When
27.08.2026, 14.00 Uhr
Where
U.a.4 in-person and via Zoom
Recordings
Please be aware that the talks may be recorded, including the questions asked by the audience after the talk.