Using images taken by NASA's Mars Perseverance rover, the researchers found that the landing site, Jezero Crater, was a large lake fed by a small river 3,7 billion years ago.
The new analysis confirms the theory that led NASA to choose Jezero Crater as the landing site for Mars Perseverance. Sediments found at the bottom of the ancient crater lake can be used to detect traces of ancient life on the red planet.
A river and a lake
The researchers' analysis clearly shows that the western wall of the crater is a large dune field formed by a river that once flowed in a nearby valley. The river fed a once-liquid lake on Mars' Jezero Crater.
Scientists, who published their analysis in the journal Science, they also revealed that flash flooding occurred in the now-desolate region. “If you look at these images, you're basically staring at a desert landscape,” he explained Benjamin Weiss, professor of planetary sciences at MIT and member of the analysis team.
There is not a drop of water anywhere, yet here we have evidence of a very different past. Something very profound happened in the history of the planet.
Benjamin Weiss, M.I.T.
Jezero, the perfect choice
Perseverance's choice to land at a spot called Jezero Crater was functional. The NASA team had assessed from images received in February that the rock formations inside had the appearance of those present in places that once hosted a watercourse. The new images, captured by Perseverance's Mastcam-Z and SuperCam Remote Micro-Imager (RMI) cameras, confirm that the western side of Jezero Crater it was once the site of a river delta.
The new MIT study explains that the lake remained calm for long periods until climate change caused flash flooding in the region. According to the researchers, the floods carried large boulders tens of miles from higher altitudes to the lake floor where they still exist today.
Next, Perseverance will search for locations from which to collect samples that will eventually be returned to Earth by future missions. Once on Earth, these samples will be analyzed for signs of ancient Martian life. “Now we have the opportunity to look for fossils,” says the team member Tanya Bosak, associate professor of geobiology at MIT. “It will take some time to get to the rocks that we really hope to test for signs of life. So, it's a marathon, with a lot of potential."
Close to a historical discovery
Since it landed on the Jezero crater on February 18, the mission Mars perseverance has successfully ticked off a list of historical records, including the first controlled flight on another planet e the first extraction of breathable oxygen from the red planet using an experimental tool called MOXI.
The Perseverance rover will spend at least two years exploring and sampling Jezero Crater. It will drop samples in specific locations on the red planet for future missions to Mars to be recovered and returned to Earth. We may be incredibly close to confirming the existence of alien life (albeit perhaps in the form of long-dead microorganisms)
