Title:
Astrophysical Drivers of Prebiotic Chemistry on Early Earth and Rocky Exoplanets

Speaker:
Dr. Vladimir Airapetian (NASA Goddard Space Flight Center)

Abstract:
Our Sun, a magnetically mild star, exhibits space weather in the form of magnetically driven solar explosive events (SEEs) including solar flares, coronal mass ejections (CME) and solar energetic particle (SEP) events. Extreme SEEs from magnetically active stars can significantly perturb magnetosphere, cause strong geomagnetic storms, initiate escape and introduced chemical changes in exoplanetary atmospheres. We use stellar magnetogram data and reconstruction of X-ray and UV emission from young solar-like stars to recover the frequency and energy fluxes from extreme events from active stars including the young Sun. I present our recent simulation results of atmospheric escape from the early Earth and rocky exoplanets based on multi-dimensional multi-fluid hydrodynamic and magnetohydrodynamic models of interactions of extreme CME and SEP events with magnetospheres and lower atmospheres. We also discuss the chemical impact of solar energetic particles on the lower atmosphere of the early Earth and its role in setting stage for prebiotic chemistry and the resolution of the long-standing Faint Young Sun (FYS) paradox. We also present observational bio-signatures of life "highlighted" by solar energetic protons to be detected by upcoming missions including James Web Space Telescope (JWST).