This picture is from Aram Chaos crater in Mars. It was taken last month by HiRISE camera of MRO-probe. The crater was named Aram Chaos because of the broken formations of the surface.

Scientists believe the crater was formed when the material under the surface dissappeared. Lowest parts of the crater contain dark sand which is coloured blue in the picture. On can also see the dunes formed by the sand right next to steep walls.

“Sulfates have been detected in the cliff walls in some areas within Aram Chaos, as well as hematite. It has been suggested that these materials were deposited within a lake setting“, was said in HiRISE project website.

See a high-resolution image here.

“HiRISE can provide interesting new things in places researchers have considered boring“, says Alfred McEwen from the University of Arizona as interviewed by Finnish space magazine Tähdet & Avaruus. “I was surprised when I saw the diversity of the surface. Instead of fine dust we can see different forms that can be created by wind and material in the air“, says McEwen in the interview.

HiRISE has provided us many new and interesting things from Mars, such as spiral forms of dust, eroded craters and ancient lava-rivers. From scientific point of view we have learned very much about the processes of the surface of Mars.

One of the interesting areas HiRISE has studied is the northern plain which, according to one hypothesis, used to be a giant ocean. If the area used to be an ocean, there should be fine grained material in that plain. “We found large amounts of big rocks in the plain“, says McEwen. By this we can conclude that the ocean hypothesis does not hold. These rocks were not seen by the earlier orbiters, but with much more powerful HiRISE camera it is possible. HiRISE is able to take large amounts of very sharp pictures around the planet.

HiRISE arrived to the orbit of Mars in March 10, 2006. The first pictures were taken in September 2006 after some corrections in the orbit of the satellite. One of the first important findings of HiRISE was done in 2007 when HiRISE found evidence of ancient flows of ground water. Lately HiRISE has studied the effects of wind on the surface of Mars. With its very accurate HiRISE camera the orbiter has found out that there are lots of effects of wind in Mars. Researchers have wondered if the winds in Mars are effective enough to create the forms of the surface because the air pressure in Mars is only less than one percentage of the air pressure on Earth. According to Nathan Bridges of Jet Propulsion Laboratory (JPL), the surface of Mars has layered wave forms on top of dunes.

In the pictures of HiRISE one can also see layers on the other side of rocks, which tells us the direction of major winds. The have been recognized already by Mars explorers, but not by earlier orbiters. HiRISE pictures can now be used to map the wind directions on of Mars.

It is also interesting that HiRISE pictures show us the effects of erosion in Mars, just like here on Earth. This has not been possible before HiRISE because the cameras of earlier orbiters have been much weaker.

HiRISE pictures do not have original colors because it is easier to see the forms of the surface through other colors. Also the contrast of HiRISE pictures is higher in order to see the forms and shadows.

For more about HiRISE and the new pictures, please visit the HiRISE website of University of Arizona. You can learn about HiRISE also in Nasa’s HiRISE website. Pictures and wallpapers can be downloaded from the server of University of Arizona. Check out also the video below in which the MRO HiRISE Images of Mawrth Vallis, Terra Sirenum and Chasma Boreale are presented.