Atmospheric correction of OMEGA data from Mars Express to detect surface composition.

摘要

Reflectance spectra, obtained from the imaging spectrometer OMEGA onboard Mars Express, are corrected for atmospheric effects to retrieve surface albedo spectra and used to investigate surface ice composition in the polar and equatorial regions of Mars. Strong, unambiguous, absorption bands, not masked by dust, are located at 1.4, 1.6 and 2.0mum for CO 2 ice and at 1.5 and 2.0mum for H2O ice. In this study, seasonal CO 2 ice and permanent H2O ice at the poles as well as residual CO2 ice in the south and seasonal H2O ice in Hellas Planitia are observed by OMEGA. In addition, evaluation of the Global Mars Multiscale Model simulation of surface ice is done to compare with OMEGA observations. Residual CO2 ice is not simulated in the South Polar Region and simulated H2O ice amounts are too small and not generated for the uppermost latitudes of the North Polar Region.