Gale Crater is a crater on Mars near the northwestern part of the Aeolis quadrangle. It is 154 km (96 mi) in diameter and believed to be about 3.5 to 3.8 billion years old.
Aeolis Palus is the plain between the northern wall of Gale Crater and the northern foothills of Aeolis Mons (also known as “Mount Sharp”), an enormous central mound of debris, rising 5.5 km (18,000 ft) above the northern crater floor and 4.5 km (15,000 ft) above the southern crater floor – slightly taller than the southern rim of the crater itself. The mound is composed of layered material and may have been laid down over a period of around 2 billion years.
The origin of this mound, actually consisting of several distinct smaller hills, is not known with certainty, but research suggests it is the eroded remnant of sedimentary layers that once filled the crater completely, possibly originally deposited on a lakebed. However, there is debate around this issue.
Observations of possible cross-bedded strata on the upper mound suggest aeolian processes, like dust or volcanic ash blown in by the wind, but the origin of the lower mound layers remains ambiguous. Numerous channels eroded into the flanks of the crater’s central mound could give access to the layers for study. In close-up images polygons are visible on the crater floor, indicating contraction due to water loss, cooling, or some other process.
NASA’s Mars rover, Curiosity, which was launched 26 November 2011, will explore Aeolis Mons after the landing on Aeolis Palus in Gale Crater within a few days, on 5/6 August 2012, depending on the time-zone you live in. Gale is also one of four prospective sites for ESA’s ExoMars.
This oblique, southward-looking view of Gale crater shows the landing site and the mound of layered rocks that NASA’s Mars Science Laboratory, Curiosity, will investigate. The landing site is in the smooth area in front of the mound (marked by a yellow ellipse, which is 20 km [12.4 mi] by 25 km [15.5 mi]).
The landing site contains material washed down from the wall of the crater, which will provide scientists with the opportunity to investigate the rocks that form the bedrock in this area. The landing ellipse also contains a rock type that is very dense and very bright colored; it is unlike any rock type previously investigated on Mars. It may be an ancient playa lake deposit, and it will likely be the mission’s first target in checking for the presence of organic molecules.
The area of top scientific interest for Curiosity is at the base of the mound, just at the edge of the landing ellipse. Here, orbiting instruments have detected signatures of both clay minerals and sulfate salts. Scientists studying Mars have several important hypotheses about how these minerals reflect changes in the Martian environment, particularly changes in the amount of water on the surface of Mars. Curiosity will use its full instrument suite to study these minerals and how they formed to give us insights into those ancient Martian environments. These rocks are also a prime target in checking for organic molecules.
More information on:
• Curiosity’s mission: http://annesastronomynews.com/lifes-molecules-could-lie-within-reach-of-curiosity/
• Curosity’s landing: http://annesastronomynews.com/curiosity-nears-daring-landing-on-mars/
• Mars: http://annesastronomynews.com/photo-gallery-ii/the-solar-system/mars-has-the-highest-mountain-and-the-largest-canyon-valles-marineris-which-is-3000-km-long-spans-600-km-across-and-is-8-km-deep-in-the-solar-system-the-ironoxide-on-its-surface-gives-it-a-re/
Image Credit: NASA/JPL-Caltech/ASU/UA