High-energy photons and particles from stars regulate the atmospheric temperature structure and photochemistry on orbiting planets, influencing the long-term stability of planetary atmospheres and the production of potential "biomarker" gases. Rocky planets orbiting low-mass stars (M dwarfs) will likely be the first exoplanets directly probed for signs of life, however, relatively few observational and theoretical constraints exist on the high-energy irradiance from typical (i.e., weakly active) M dwarf exoplanet host stars. In this talk, I will describe results from an ongoing panchromatic survey (Chandra/XMM/Hubble/ground) of M and K dwarf exoplanet hosts. The MUSCLES Treasury Survey combines UV, X-ray, and optical observations, reconstructed Lyman-alpha and EUV (10-90 nm) radiation, and next-generation stellar atmosphere models to provide realistic inputs for modeling the stability and climate on potentially habitable planets around red dwarfs.
Thu, 10.10.2019 14:00