Landing site of NASA's Mars 2020 may be a fossil hotspot

Silica is a mineral that is known to play a role in fossil formation. This discovery can help answer the question of whether there has ever been life on Mars.

Hydrated silica has been found in the Jezero crater on Mars.
Hydrated silica has been found in the Jezero crater on Mars 2019.

Hydrated silica has been found in the Jezero crater on Mars, the future landing site for NASA's Mars 2020 rover

From a orbit around Mars, different space probes map the surface of the planet in detail. One of those probes is the Mars Reconnaissance Orbiter (MRO) from NASA. This unmanned spacecraft contains, among other things, the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM). This instrument measures visible light and infrared electromagnetic radiation coming from Mars.

Researchers from the US and China have now analyzed CRISM measurements and detected the presence of a special mineral on the surface of the red planet: hydrated silica.

Silicification on mars 2019.

Silica, which is found in toothpaste, also plays a role in the formation of fossils, as we know from fossil finds on earth. This happens during a process called silicification. In this process, rock slowly breaks down as a result of natural processes and released silica minerals end up in present water.

Silicification on mars 2019.
Silicification on mars 2019.

This water, containing the minerals, then penetrates the cells of dead organisms, after which it forms a gel. Over time, this gel dries out. This creates a crystalline structure that mimics the internal shape of the organism. When the water has finally completely evaporated, the formed structure can become petrified and a fossil of the organism is created.

Just like on earth, the silica in the Jezero Crater on Mars should also be able to form fossils. At least, if there has been life on Mars, and in that spot.

NASA wants to send its next spacecraft to Mars: Mars 2020.

NASA is busy asking if there is or has been life on Mars and has been sending rovers to mars. It is planned that this rover will land on Mars in February 2021 in the so-called Jezero Crater, a gigantic surface with a diameter of 49 kilometers where once there may have been a lake. The Jezero Crater is also the place where the silica was found.

NASA’s Mars 2020 Rover 2019.
NASA’s Mars 2020 Rover December, 2019.

To be precise, the silica lies in a delta deposit of what were probably once rivers, which flowed into the hypothetical lake that eventually formed the Jezero Crater.

Mars 2020 Landing Site  Jezero Crater.
Mars 2020 Landing Site  Jezero Crater, December 2019.

Such a river delta deposit is a piece of land, for example in a lake, which has been formed by years of precipitation of natural materials that are brought by rivers. On earth, such deposits are often places where silicate fossils are found.

Mars 2020 can confirm exactly where the silica lies in the crater. The rover can also use chemical analyses to investigate what the silica consists of and where it could come from. 

If it turns out that the silica was formed in the bottom layer of the river delta deposit, then according to the researchers this is a promising scenario for finding possible signs of life on Mars.