Mars used to be a wildly different land.
Though the red planet is bone dry today, NASA’s Curiosity rover recently rumbled by poignant evidence of an ancient watery world. The car-sized robot snapped an image of a unique rock that looks like its composed of stacked layers. Such a rock likely formed “in an ancient streambed or small pond,” the space agency wrote.
Curiosity is winding up through the foothills of the three-mile-tall Mount Sharp, where it’s encountering a place where these streams and ponds once carried red sediments through the landscape. Ultimately, some of these sediments were deposited in stacks.
A flaky, well-layered rock on Mars.
Credit: NASA / JPL-Caltech / MSSS
And at lower elevations, there’s clear evidence that Mars didn’t just have ponds — it was warm and moist enough to harbor big lakes.
Curiosity’s robotic sibling, the Peservance rover, is now journeying through the planet’s Jezero Crater, a place NASA suspects contained a lake and river delta. Though the water is all gone today, the robot has specialized equipment intended to identify past hints of microbial life that could have potentially dwelled on a wetter, different Mars.