The Perseverance rover has been exploring Mars’s Jezero Crater as part of its mission to search for evidence of ancient life on Mars. The history of water is key in the search for life, and it is currently thought that Mars lost its water around 4 million years ago. Now, the rover has identified evidence of what was once one of the deepest and fast-flowing rivers yet discovered on the planet.
The rover captured a series of hundreds of images using its Mastcam-Z instrument, which were put together into this mosaic showing a hill structure called Pinestand. In the image, you can see the many layers left behind by the flowing river, which were formed by deposits of sediment.
The way the sedimentary rocks are structured suggests that the river passing through this area was fast and powerful. “Those indicate a high-energy river that’s truckin’ and carrying a lot of debris. The more powerful the flow of water, the more easily it’s able to move larger pieces of material,” said Libby Ives of NASA’s Jet Propulsion Laboratory in a statement. “It’s been a delight to look at rocks on another planet and see processes that are so familiar.”
Evidence there was once a river here can also be seen in this mosaic of nearby rocks, which have a banded structure.
“The wind has acted like a scalpel that has cut the tops off these deposits,” said Perseverance science team members Michael Lamb of Caltech. “We do see deposits like this on Earth, but they’re never as well exposed as they are here on Mars. Earth is covered in vegetation that hides these layers.”
These images were taken as Perseverance explores an area of the crater which is the site of an ancient river delta. This feature is one of the reasons that Jezero is such an exciting place to explore, as it is a promising location to look for evidence of life.
“What’s exciting here is we’ve entered a new phase of Jezero’s history. And it’s the first time we’re seeing environments like this on Mars,” said Perseverance’s deputy project scientist, Katie Stack Morgan of JPL. “We’re thinking about rivers on a different scale than we have before.”
