NASA's Perseverance may have found first-of-its-kind evidence of a rollicking river on ancient Mars

New images captured by NASA's Perseverance rover may show signs of a powerful river that existed on Mars in the past. These images, captured by the rover's Mastcam-Z instrument, reveal a rollicking river that was not only deeper but also faster-moving than any previously documented on the Red Planet.

According to NASA, this river was part of a vast network of waterways that once coursed through Jezero Crater, the region where the rover has been diligently exploring since its touchdown over two years ago.

The two new Mastcam-Z mosaics, composed of hundreds of images, reveal important clues: coarse sediment grains and cobbles.

"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, a postdoctoral researcher at NASA's Jet Propulsion Laboratory in Southern California, which operates the Perseverance rover.

The first mosaic captured by Perseverance is of a location nicknamed "Skrinkle Haven" within the Jezero Crater. Scientists are sure the curved layers here were formed by powerfully flowing water, but they aren't sure about its kind - a river such as the Mississippi or a braided river like Nebraska's Platte.

The rover captured another mosaic of a hill nicknamed Pinestand which is part of the curvilinear unit - a series of curving bands of layered rock within Jezero Crater. The isolated hill bears sedimentary layers that curve skyward and scientists think these tall layers could have been formed by a deep, fast-moving river although they're exploring other explanations, as well.

"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. We're thinking about rivers on a different scale than we have before," said Perseverance's deputy project scientist, Katie Stack Morgan of JPL.

New images from @NASAPersevere may show signs of a what once was a rollicking river on Mars. Explore this mosaic, which was stitched together from hundreds of the rover's images, and learn more at: https://t.co/c4wisRvxWa pic.twitter.com/PezuRCdDLA

— NASA JPL (@NASAJPL) May 11, 2023