The discovery allows scientists to affirm that it is “a substance or a structure that could testify to the existence of life on Mars in the past” but it is also true that these molecules “could also have been produced without there being life” .
NASA’s Perseverance rover has found rocks that contain it on the surface of Mars organic molecules. According to experts from the American space agency, these molecules could be “a possible” signature “of life”. The discovery allows scientists to affirm that it is “a substance or a structure that could testify to the existence of life on Mars in the past” but it is also true that these molecules “could also have been produced without there being life” . The announcement came from the mission leaders during an online press conference.
What is Perseverance doing
One of Perseverance’s tasks on Mars is related to astrobiology: to collect samples that may contain signs of past microbial life. Plans call for these samples to be collected by future NASA missions, in collaboration with ESA (the European space agency), and brought to Earth for in-depth analysis.
The rover is focusing on an ancient crater river delta Lake, an area long considered by scientists to be one of the most promising for finding signs of ancient microbial life on Mars. He collected 4 samples, bringing the total count of scientifically interesting rock samples to 12.
What the rover found
Organic molecules are made up of a wide variety of compounds consisting primarily of carbon and usually include hydrogen and oxygen atoms. They can also contain other elements, such as nitrogen, phosphorus, sulfur. There are chemical processes that produce these molecules that do not require life, but some of these compounds are the very chemical building blocks of life. For this reason, the presence of these specific molecules is considered a potential “biofirmaOr a substance or structure that could be evidence of past life (but could also have been produced without the presence of life).
Previous and current samples
Already in 2013, NASA’s Curiosity rover had found evidence of organic matter in rock dust samples, and Perseverance itself had already detected organic substances in the Jezero crater, where it is still operating. However, the latest samples were taken in an area where, in the distant past, sediments and salts were deposited in a lake under conditions where life could potentially exist: the instrument Sherloc (Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals), which analyzes the samples taken, recorded on the rock called “Wildcat Ridge” the most abundant organic detections of the mission to date. “In the distant past, the sand, mud and salts that now make up the Wildcat Ridge specimen were deposited under conditions where life could potentially flourish,” he said. Ken Farleya scientist on the Perseverance project at Caltech in Pasadena, California.