The planetary effective surface temperature alone is insufficient to characterize exoplanet atmospheres and their stability or evolution. Considering the star-planet system as a whole is necessary, and a critical component of the system is the photoionizing stellar extreme ultraviolet emission (EUV; 100-912 {\AA}). EUV photons drive atmospheric mass loss through thermal and nonthermal processes, and an accurate accounting of the EUV energy deposition in a planet's energy budget is essential, especially for terrestrial habitable zone planets and close-in gaseous planets. Direct EUV observations of exoplanet host stars would require a new, dedicated observatory. Archival observations from the EUVE satellite, models, and theory alone are insufficient to accurately characterize EUV spectra of the majority of exoplanet host stars, especially for low-mass stars.
@article{arxiv.1903.05718,
title = {EUV influences on exoplanet atmospheric stability and evolution},
author = {Allison Youngblood and Kevin France and Tommi Koskinen and Luca Fossati and Ute Amerstorfer and Herbert Lichtenegger and Jeremy Drake and James Mason and Brian Fleming and Joel Allred and Zachory Berta-Thompson and Vincent Bourrier and Cynthia Froning and Cecilia Garraffo and Guillaume Gronoff and Meng Jin and Adam Kowalski and Rachel Osten},
journal= {arXiv preprint arXiv:1903.05718},
year = {2019}
}
Comments
Science white paper submitted to the Astro2020 Decadal Survey. 7 pages, 2 figures