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.
The HiRISE scientists monitor these regions to help in understand the climatic record stored in the ice sheet itself.
What else did HiRISE see this week?
These cool-looking dunes look reminiscent of Pac-Man, and they might even be moving across the surface of Mars! They are approximately 100 meters across and are traversing a bumpy, hard terrain, pushed across the surface by the winds on Mars. The HiRISE team will take more images of this dune field in subsequent passes to determine whether these dunes are really moving.
This image shows a gullied crater in the Southern mid-latitudes with light-toned deposits near the center of its floor, and two areas of collapsed terrain at the northern and southern edges of the crater floor.
For more information on each of these images, go to the HiRISE website to see all the wonderful images from Mars.
Explore further: The heart of an astronaut, five years on