Non-Thermal Oxygen Escape on Mars in the Presence of Gravity Waves

Extensive measurements made over the past two decades have indicated the widespread and frequent occurrence of gravity waves in the atmosphere of Mars. Gravity waves are able to significantly modify the atmospheric structure and potentially affect atmospheric escape. This study is devoted to examining the hot O escape variability on Mars in the presence of gravity waves with the aid of the Wentzel-Kramers-Brillouin approximation and the multi collision model as well as the multi-instrument MAVEN data set. Our calculations suggest that the hot O escape probability tends to be enhanced or suppressed in the presence of gravity waves near the Martian exobase and the impacts vary substantially with the ejection angle and nascent energy of hot O, and gravity wave characteristics. Further study indicates that although gravity waves play a negligible role in the averaged hot O escape probability, they are able to enhance hot O escape flux by 20% via altering the hot O production rate rather. Since gravity waves are omnipresent on any planetary body with a permanent atmosphere, they are expected to affect the non-thermal escape on solar system and extrasolar bodies. We evaluate the impacts of gravity waves on the non-thermal escape of oxygen on Mars for the first time Gravity waves can alter local oxygen escape probabilities for some conditions yet have little effect for the average condition Gravity waves are able to enhance oxygen by similar to 20% primarily via enhancing hot oxygen production