Rover Perseverance has found possible traces of microbial life in a Jezero crater rock on Mars.
After a year of analysis, the rock champion called Sapphire Canyon remains the best candidate of the mission Perseverance to contain traces of ancient processes of microbial life on Mars. The rover of the NASA collected this sample from a rock known as Cheyava Falls, located in an ancient river bed now dry inside the crater Jezero.
According to a study published in the magazine Naturethe material contains possible Biofime, i.e. substances or structures that could have a biological origin. A Biofirma is not a definitive proof of life, but a clue that can be explained both by biological processes and geological or chemical phenomena. For this reason further data is needed to confirm the hypothesis.
Sean Duffy, NASA administrator, said at the press conference that this discovery is the closest so far to identifying Life on Mars: «The identification of a potential biological signature on the red planet is a revolutionary discovery that will progress our understanding of Mars. NASA will continue to carry on high -level scientific research, with the aim of making the feet of American astronauts on Martian soil put one day ».
Where the champion was found
Perseverance has come across the Cheyava Falls in July 2024, while exploring training Bright Angel: a set of rocky outcrops on the margins of the Valle della Neretva, an ancient water course about 400 meters wide that once poured water into the Jezero crater.
Nicky Fox, associated administrator of Directorate Mission Science Mission of NASA, stressed that the discovery is the result of the strategic planning of the mission:
“With the publication in a scientific journal, these data are now available to the scientific community to be further studied, so as to confirm or deny their biological origin”.
What the tools found
The sedimentary rocks of the training Bright Angel contain clay and silt, materials that on earth preserve well traces of microbial life. Also, they are rich in organic carbon, sulfur, oxidized iron e phosphorus.
Joel Hurowitz, a mission scientist and the main author of the study, explained that the combination of these compounds could have provided energy to any microbes.
The first tools to analyze the rock were Pixl (Planetary Instrument for X-Ray Lithochemistry) And Sherloc (Scannning Habitable Environments with Raman & Luminescence for Organics & Chemicals).
During the study of Cheyava Falls – a arrow -shaped rock, one meter long and 60 cm wide – have emerged Colored spots that could have been left by microbes, who would have exploited organic carbon, sulfur and phosphorus as a source of energy.
High resolution images showed a characteristic reason, called “Leopard spots”, made up of two iron rich minerals: Vivianite (hydrated iron phosphate) e Greigite (iron sulphide).
-
There Vivianite, on earth, is found in the sediments, in the tobles and close to organic matter in decomposition.
-
Some Terrestrial microbes instead produce gigite.
The presence of these minerals could indicate biological processes related to the transfer of electrons, which microbes could have used to obtain energy. However, it is possible that minerals have also trained lifeless (abiotic processes), for example due to high temperatures, acid environments or bonds with organic compounds.
The rocks of Bright Angel, however, do not show traces of these extreme conditions: for this reason the possibilities that they are life products are considered quite high.
A surprising discovery
The result is particularly interesting because it concerns some of the Younger sedimentary rocks ever studied by the mission. In the past it was thought that any signs of life were confined to the oldest rocks.
This discovery suggests that Mars may have remained Loorly habitable than hypothesized and that even the oldest rocks could contain signs of life, even if more difficult to identify.
Katie Stack Morgan, scientist of the project Perseverances, however, recalled the need for caution:
«Astrobiological statements, especially if they concern possible traces of extraterrestrial life, require extraordinary evidence. Although the abiotic explanations are less likely, we cannot exclude them completely ».
The context of the mission
Sapphire Canyon is one of the 27 samples collected by the Rover since he landed in Jezero crater, in February 2021.
In addition to the tools to analyze rocks and minerals, Perseverance also has:
-
a Meteorological station, useful for future human missions;
-
champions of Spaziale material, so as to test its behavior in the Martian environment.
