CRISM reveals new views of Martian north pole

POC: Dr. Adrian Brown

Dr. Adrian Brown of SSX and the STI Institute has published a paper detailing his research into the properties of the water and carbon dioxide ice around the north pole of Mars. Dr. Brown used 3 Mars years of data from the CRISM imaging infrared spectrometer to determine the retreat rate of the polar cap during springtime. His group found that contrary to previous reports, the Martian water ice in the north pole gets warm enough to grow by a process called ‘thermal metamorphism’, much as water ice crystals grow after they fall as fine ice grains into dirty snowballs.

His group also showed that as the polar cap retreats, it is not symmetrical in composition, the water ice part of the cap in fact covers up the CO2 part of the cap around mid spring, in a process they have termed ‘asymmetric retreat’ of the water ice cap. The reason for this asymmetric retreat suggested by this paper is that wind is blowing water ice particle from rough ice outliers on the outskirts of the cap that are exposed as the carbon dioxide ice disappears. This process is thought to be unique in the solar system.

Brown’s north polar study caps off his research into the Martian south polar region using CRISM that was published in 2009.