The Perseverance rover on Mars has collected two samples of a rock that turns out to be probably volcanic, NASA announced on Friday, stressing that the presence of salts in these samples was the indicator of favorable conditions to possibly detect traces of life. Ancient.
“It looks like our first rocks reveal a potentially habitable environment,” Ken Farley, chief scientist at Perseverance, said in a statement. At the beginning of August, the rover had failed in its first attempt to take a sample, the stone then selected (called Roubion) being too friable.
The rover therefore continued on its way, and finally selected another harder stone, called Rochette. Perseverance carried out a first sample last week, and two days later a second, in the same stone, considered particularly interesting by NASA. The two collected cores are now in sealed tubes and kept inside the rover. They are about 6 cm long each.
The rover operates in an area called Jezero Crater, which scientists believe was home to a deep lake 3.5 billion years ago. However, they were not sure whether the rocks there were volcanic or sedimentary in nature.
Samples to be repatriated
“Based on observations made so far, we interpret Roubion and Rochette to be ancient volcanic lava flows,” Katie Stack Morgan, member of the rover’s science team, told a press conference. Volcanic rocks are particularly useful because they can be dated precisely.
In addition, these rocks “show signs of substantial interactions” with water, she continued. They indeed contain mineral salts, which were probably deposited when the water evaporated. This confirms that water has been present in the crater for a long time, says NASA.
Importantly, “the mineral salts in those first two carrots could have trapped tiny bubbles of Martian water,” the space agency explains. “Salts are great minerals for preserving signs of life on Earth, and we would expect that to be the same for rocks on Mars,” said Katie Stack Morgan.
The objective of the mission is to look for signs of ancient life on Mars, such as traces of microbial life fossilized in the rocks. Sampling will continue, with Perseverance transporting more than thirty additional tubes for other samples.
NASA then plans a mission to bring the samples back to Earth in the 2030s, so that they can be analyzed by much more sophisticated instruments than those that can be brought to Mars.