For over a year, we can see much surprising things about the images we send Curiosity. The rover is currently in the Gale crater, and during his journey, he crossed repeatedly sedimentary areas. We will look at two specific locations.
At both stops, Curiosity rover crossed sites rich in sediments, probably the bottom of a lake that was at the bottom of Mount Sharp, there are about 3 billion years. This lake was to be powered by water runoff from the flanks of the mountain, which rises to 5500 m height above the floor of Gale Crater.
What Curiosity shows when he walks along the sedimentary grounds ?
First, recall that the NASA rover arose on August 6, 2012 with high precision inside the Gale Crater, which measures 155 km in diameter.
This crater is located on the Martian equator between the southern highlands and the northern lowlands.
The mountain was renamed Aeolis Mons, and the flat part of the crater, Aeolis Palus.
Aeolis Mons reveals a laminated structure which would be formed due to the share of liquid water during a very long geological time. This mountain would be a huge sedimentary residue that may have been secondarily sculpted by wind erosion but also by other processes more or less known.
Curiosity's mission is to determine if Mars was, or still is, conducive to the development of life. It should answer questions such as :
Water has she been present and how long ?
Are there traces of a past life, so obvious or probable ?
This site has also been selected by NASA because of the significant preservation of traces of these ancient times. The region where Curiosity is now moving (Aeolis Palus) corresponds to one of the oldest sedimentary layers.
Therefore, if signs of past life exist, they will certainly very old, and as may be even more primitive than on Earth appear. In addition, wind erosion, important on Mars, will probably greatly reduced the relief of potential fossils.
Yet it seems that we can distinguish very interesting traces.
Already, during sol 136-149, you could see small rounded rock formations along particular lines.
On a closer look, this is what it looked like.
Then, the rover moved in Gale Crater to bypass the final destination : Sharp mountain.
On the way, he stopped his march to achieve another sedimentary site where he drilled a sandstone slab called Windjana.
Here we see again, but much more precise, small round formations that appear obviously hollow.
Here are others that you can find around Curiosity.
Some are pedunculated, others not.
What is it exactly?
We can say that these structures are included in the sedimentary rocks, that is very conducive to fossilization process.
They result from the accumulation of sediment that settles very slowly at the bottom of the water ...
... but their rounded shape evokes no means ordinary pebbles, as can be seen in this another shot of the same panorama.
In case of biogenic rocks, these round structures could be fossils of ancient aquatic animals.
They could correspond to fossils found on Earth as sponges (marine sponges), primitive invertebrate animals.
Also, it could be equivalent Balanus, crustaceans whose fossils have the following appearance.
They can also look like fossilized coral, like these ...
... Or even more clearly, as these.
Here is an example of extremely primitive fossil coral named Nemiana Simplex was found in Novodnestrovsky career in Podolia (Ukraine). These primitive corals dated Precambrian, first geological era in the history of the Earth, ranging from -4.5 billion years to -540 million years. They had a body shaped bag without tentacle. Here they are present on a block of very fine-grained sandstone dating from 620 million years.
Here is another example of Nemania simplex, unlike current corals, tended only wear one isolated polyp. Thus, it should look like this Martian picture :
If these fossil structures correspond to a trace of very primitive marine life, more obvious signs of complex life will appear as Curiosity rise in altitude to younger sedimentary layers.
Rendez vous in a few weeks or months.
To view the slideshow enlarged, click a picture.
You have serious knowledge in geology or paleontology : give your opinion.
Exobiology is a new science and your expertise in various scientific sectors is needed to establish the truth.
And most importantly, view panoramas offered to support your own opinion. Pictures, stunning precision are made by the photographer Andrew BODROV.