image: This is a circular pit (diameter, 4 km; depth, 65 m) within the CO2 radar-detected deposit. The pit is floored with a thin fractured water-ice layer (upper left inset), which is mantled partially by the “Swiss cheese” terrain of the South Pole residual cap. Details within the pit are shown in the other insets. All of these features indicate CO2 sublimation mechanisms at work. Illumination from upper left; part of NASA/MRO HiRISE image PSP_003728_0930. This image relates to an article that appeared in the April 21, 2011, issue of Science Express, published by AAAS. The study, by Roger J. Phillips at Southwest Research Institute in Boulder, Colo., and colleagues, was titled, "Massive CO2 Ice Deposits Sequestered in the South Polar Layered Deposits of Mars." view more
Credit: Image courtesy of NASA/JPL-Caltech/University of Rome/Southwest Research Institute