Scientists suspect that the mountain toward which the rover Curiosity, was created not lacustrine silt.
The layered rocks of Mount Sharp may have formed from the dust, wind-borne. (Photo by NASA / JPL-Caltech / MSSS.)
Wind, not water, is responsible for most of the sediments in the crater, where the rover is working Curiosity, says an analysis of data obtained from orbit.
If the rover will confirm this assumption, reaching the central peak of the crater in the next year, the chances of finding organic material in those areas can be considered as zero.
Last August, Curiosity down in Gale crater 154 km in diameter. The main objective of the mission is to get to the mountains Eolida (also informally known as Mount Sharp), a height of 5 km and analyze its sediments. Some researchers have suggested that the bulk of the peak, at the foot of which are clay and sulfate minerals formed lake sediments. "If Mars has lacustrine sediments, it is one of the best places where they should look," — says Don Sumner, University of California, Davis (USA), member of the project Mars Science Laboratory.
However, a study conducted by Edwin Kyte from the California Institute of Technology (USA) and his colleagues drew the picture of the dryer. Based on the images obtained by the probe Mars Reconnaissance Orbiter, scientists have measured the orientation of the rock layers exposed in several places at the base of the mountain. Instead of planar layers which would be expected from the lake sediments, they discovered portions inclined outwardly at about 3 °. Calculations suggest that this orientation occurs during the formation of the layers of dust filled in the crater of the wind.
If this is indeed the case, Curiosity will be difficult to find a place, indicating an environment conducive to life. In addition, the search for organic materials become complicated, because the deposits formed by wind, accumulated more slowly than the lake, and therefore longer remain vulnerable to solar radiation and oxidizing agents.
But Ms. Sumner did not believe that the slope of the rock layer eliminates the possibility of the formation of the lake. For example, the asteroid that created the crater Gale, could form a small central mound, and the water was flowing through the peak, has led to the fact that the lake sediments are the sole is thicker than the top. Over time, they are sealed and leaned toward the edge of the crater. Another team member Gary Curiosity Kocourek from the University of Texas at Austin (USA) agreed: "The wind is not the only way to explain this inclination."
Curiosity will try to test these hypotheses, reaching the base of the mountain Sharpe in 2014 after a 10-kilometer journey. Its camera will be quite close to the peak to see how truly inclined deposits. And even if it turns out that the mountain is mostly formed by the wind, there is no reason to lose heart, because we learn a little more about what happened on Mars in ancient times.
The study is published in the journal Geology.
Prepared according to Nature News.