After he tumbled in Jezera Crater for 550 Martian days, NASA’s Perseverance rover collected nearly half of its planned collection of rocks, including some containing organic molecules, a possible indication that life may have flourished there more than 3 billion years ago. These are compounds that contain carbon, and often hydrogen or oxygen, which are probably critical to the formation of life.
“We found rocks that were deposited in a potentially habitable environment in this lake, and we were looking for potential biosignatures” that may have been produced by life, Ken Farley, Perseverance Project Scientist at the Cal Institute of Technology, said at a news conference today . conference at NASA’s Jet Propulsion Laboratory in Pasadena, California. In fact, the Perseverance team chose the crater as the landing site for the rover for this reason. It seems that this site of an ancient river delta is a convenient place for microorganisms that appeared and evolved long ago, and an opportunity to finally answer the question: “Are we alone in space?”
However, Farley points out, organic molecules could have been produced in other ways – they can also be made through abiotic natural processes. But Percy, as the rover is sometimes called, cannot definitively determine their origins on his own. That’s why NASA and the European Space Agency are planning a sample return mission to collect different rocks from the region and send them back to Earth in the early 2030s.
The Perseverance team expects the rover to have a long service life, like its predecessor, Curiosity, which is still operational. (Perseverance is actually the fifth NASA rover to be deployed to the Red Planet.) Their preferred plan is for Perseverance to deliver the team’s favorite rock samples to a new lander equipped with a small rocket that will launch the samples to an orbiter that will then deliver them to Earth. If the mission goes as planned, the team will launch an orbiter and a lander from Earth to Mars in 2027 and 2028, respectively. A spacecraft loaded with rock samples will deliver them to the desert of western Utah in 2033.
NASA also has a backup plan. If anything happens to Percy over the next few years, the rover will also store some samples in a safe, flat location where they can be easily retrieved. Since the planet has little to no weather and few major earthquakes to damage the samples, the cache must remain intact until the lander arrives. This mission will also include two helicopters built like the Ingenuity craft already assisting the Perseverance mission, which can be used to retrieve samples.
Mars today is completely uninhabitable. With very little atmosphere left on the planet, it is a cold, arid wasteland exposed to cosmic radiation. But scientists believe it may have been a much more hospitable place billions of years ago, when it was more temperate and home to flowing liquid water. This makes it the closest world to Earth that may have once been inhabited — even if only by microbes.