The balance sheet of the 12 first drilling and rover sample collections Perseverance in the Jezero crater, on March, is particularly positive. The instruments make it possible to know that there are many organic molecules… But it will still take a long time to know their origin.
Beware, therefore, of hasty conclusions.
quality holes
Last month, NASA’s large Perseverance rover was able to collect its twelfth sample of Martian soil from the slopes of Jezero Crater. An operation that is never routine, especially since the scientific teams select the most suitable drilling sites with extreme care.
For his second scientific campaign (the first had led him to collect materials from the “bottom” of the crater), Perseverance is on the slopes of the Jezero delta. There where, about 3.5 billion years ago, several research teams believe that the conditions were the most favorable for a possible form of life on Mars to leave traces in the sediments. The latter have long since dried and hardened… Not without keeping within them a large concentration of organic molecules. This was detected by the SHERLOC instrument, located at the end of Perseverance’s mobile arm, in areas that were then drilled.
Molecules yes, but the good ones
If they are part of the “building blocks of life”, organic molecules are not necessarily proof that life was once present on Mars. To take this step, it would be necessary to show unequivocally that the molecules in question, detailed, could only have been produced by living organisms. Which, of course, Perseverance cannot do… And this is the very reason why NASA, with the help of ESA, wishes one day to repatriate these same samples to Earth.
Here, the types of sediments in which Perseverance managed to drill preserve the fossils very well… We will therefore have to wait. However, and this is already good news, it at least proves that the choice of the Jezero crater as a harvesting site was a good one! If, on the contrary, the instruments had not detected any organic molecule, the quest would have been even more complex (even impossible).
Need a big lab
While waiting to find out if these are indeed “biosignatures” and if the conditions were all met for life forms (at least microbial) to exist on Mars so long ago, the rover will continue its mission. .
In recent days, the teams have programmed a small morning research routine: it is right in the middle of winter on Mars and the scientists would very much like to observe frost formations. There are still things to learn on the red planet…
Source : NASA
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