The Interaction of Venus-Like, M-Dwarf Planets With the Stellar Wind Of Their Host Star

Cohen, O. and Ma, Y. and Drake, J. J. and Glocer, A. and Garraffo, C. and Gombosi, Tamás (2015) The Interaction of Venus-Like, M-Dwarf Planets With the Stellar Wind Of Their Host Star. ASTROPHYSICAL JOURNAL, 806 (1). ISSN 1538-4357

Preview

Text 1504.06326.pdf Available under License Creative Commons Attribution. Download (8MB) | Preview

Abstract

We study the interaction between the atmospheres of Venus-like, non-magnetized exoplanets orbiting an M-dwarf star, and the stellar wind using a multi-species Magnetohydrodynaic (MHD) model. We focus our investigation on the effect of enhanced stellar wind and enhanced EUV flux as the planetary distance from the star decreases. Our simulations reveal different topologies of the planetary space environment for sub- and super-Alfv´enic stellar wind conditions, which could lead to dynamic energy deposition in to the atmosphere during the transition along the planetary orbit. We find that the stellar wind penetration for non-magnetized planets is very deep, up to a few hundreds of kilometers. We estimate a lower limit for the atmospheric mass-loss rate and find that it is insignificant over the lifetime of the planet. However, we predict that when accounting for atmospheric ion acceleration, a significant amount of the planetary atmosphere could be eroded over the course of a billion years. Subject headings: planets and satellites: atmospheres - planets and satellites: magnetic fields - planets and satellites: terrestrial planets - magnetohydrodynamics (MHD)

Actions (login required)

Edit Item