How the martian residual south polar cap develops quasi-circular and heart-shaped pits, troughs, and moats
نویسندگان
چکیده
The martian Residual South Polar Cap (RSPC) is a 1–10 m thick deposit of permanent CO 2 ice perched on the much larger H 2 O ice cap. The CO 2 ice is dissected into mesas by erosional landforms that can be broadly classified as (i) quasi-circular pits, (ii) heart-shaped pits, (iii) linear troughs, and (iv) moats. We use HiRISE (25–50 cm/px) images taken at a cadence of days to months to track meter-scale changes in the RSPC in order to investigate the mechanisms that lead to the development of these four distinct
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