Water vapor deposition from the inner gas coma onto the nucleus of Comet 67P/Churyumov-Gerasimenko

Liao, Ying; Marschall, Raphael; Su, C.C.; Wu, J.S.; Lai, I.L.; Pinzón Rodríguez, Olga Janeth; Thomas, Nicolas (2018). Water vapor deposition from the inner gas coma onto the nucleus of Comet 67P/Churyumov-Gerasimenko. Planetary and space science, 157, pp. 1-9. Elsevier 10.1016/j.pss.2018.04.014

Preview	Text 1-s2.0-S0032063317303525-main.pdf - Accepted Version Available under License Creative Commons: Attribution-Noncommercial-No Derivative Works (CC-BY-NC-ND). Download (2MB) | Preview
	Text 1-s2.0-S0032063317303525-main.pdf - Published Version Restricted to registered users only Available under License Publisher holds Copyright. Download (3MB)

Rosetta has detected water ice existing on the surface of Comet 67P/Churyumov-Gerasimenko in various types of features. One of particular interest is the frost-like layer observed at the edge of receding shadows during the whole mission, interpreted as the recondensation of a thin layer of water ice. Two possible mechanisms, (1) subsurface ice sublimation and (2) gas coma deposition, have been proposed for producing this recondensation process and diurnal cycles of water ice. Previous studies have demonstrated both mechanisms based on simplified models. More precise and modern models are yet insufficient when addressing the gas-coma-deposition mechanism. We aim to study the recondensation from the inner water gas coma of the 67P/Churyumov-Gerasimenko with more physical constraints including the OSIRIS images, nucleus shape model, and insolation conditions. We compute, for the first time, the backflux distributions from the coma with various boundary conditions. Numerical simulations of this gas-coma-deposition process show that the equivalent water ice deposition can be up to several microns in an hour of accumulation time close to the perihelion passage, which is comparable with the simulation results of the other subsurface-ice sublimation mechanism.

Interest & Impact

Downloads

176 since deposited on 08 May 2018
20 in the past 12 months

Citations

5 Citations in Web of Science ®
6 Citations in Scopus

Search

in Google Scholar™

Services

Actions (login required)

Edit item

Actions (login required)

Edit item