Previous images of large channels on Mars and giant wave-like features on its surface called “megaripples” indicate that the planet suffered from catastrophic floods in the past. Now, a team of scientists has used data gathered by the Curiosity rover to prove that megafloods swept across the Gale crater around 4 billion years ago. “We identified megafloods for the first time using detailed sedimentological data observed by the rover Curiosity,” said Alberto G. Fairén, co-author of the paper published by Nature. “Deposits left behind by megafloods had not been previously identified with orbiter data.”
The team comprised of scientists from Jackson State University, Cornell, the Jet Propulsion Laboratory and the University of Hawaii used images taken by the Mars Hand Lens Image and Mastcam cameras on board the Curiosity rover to observe rocks and minerals in the Gale crater. What they found were sediments that they determined were deposited by gigantic flash floods that happened after Mt. Sharp and the Gale crater first formed.
They believe that the floods were caused by a huge meteoric impact that generated enough heat to melt massive amounts of ice on the planet. The event released carbon dioxide and methane, which combined with water vapor to form a warm and wet climate for a short time. This led to torrential rains across the planet, and the waters (along with the sediments) that slid off Mt. Sharp flooded the Gale crater. So, what does this mean exactly?
As you most likely know, the presence of water could mean the presence of life. That’s why NASA and other space agencies have been trying to find evidence of water on other celestial bodies in our solar system. “The planet had the conditions needed to support the presence of liquid water on the surface – and on Earth, where there’s water, there’s life,” Fairén explained. It’s now the Perseverance rover’s job to find evidence of ancient life on our planetary neighbor after it lands on the Martian surface in February 2021.