Latest from Mars: Massive polar ice cliffs, northern dunes, gullied craters
Several gorgeous images are in this weeks update from the HiRISE camera on board the Mars Reconnaissance Orbiter. This lovely image shows the cliffs at the edges of huge ice sheet at the North Pole of Mars. These cliffs are about 800 meters (2,600 feet) high, and the ice sheet is several kilometers thick at its center. This is a great spot to look for ice avalanches that HiRISE has captured previously. The HiRISE team said that the slopes of these cliffs are almost vertical, plus dense networks of cracks cover the icy cliff faces making it easier for material to break free. The team regularly monitors sites like this to check for new blocks that have fallen. You can look for yourself to see if any avalanches have occurred since the last image was taken of this area, almost exactly one Martian year ago.