“Perseverance rover’s photos suggest a deep and fast-flowing river once existed on Mars, changing our understanding of a warm, humid Mars”

2023-05-12 16:24:11

Photos from Mars rover Perseverance suggest that a fast-flowing river could be found in the Jezero crater long ago. And that significantly changes our view of warm, humid Mars.

Mars rover Perseverance is currently exploring the top of a 250-meter mound made up of sedimentary rock. That rock consists of wavy layers, which indicates that it was deposited by flowing water. Based on the images that Perseverance made of the rock layers, scientists tried to form an image of the water that deposited the sediments here long ago. In particular, they wondered whether that water formed relatively shallow streams – something for which they had already found evidence through the eyes of Mars rover Curiosity in the Gale crater – or whether things were perhaps a bit more intense in the Jezero crater. .

Rock layers
To this end, Persverance took hundreds of photos of the rock layers, which the researchers then analyzed. And they soon discovered that the rock layers contain fairly coarse sediment and even small pebbles. It indicates that the scientists did not find traces of a rippling stream here, but of a fast-flowing and quite deep river, explains researcher Libby Ives. “The more powerful the water stream, the easier it can move larger pieces of material.”

Startling
The find in the Jezero crater is startling; never before have researchers on Mars found traces of a river so deep and so fast-flowing. “It’s the first time we’ve seen such areas on Mars,” says researcher Katie Stack Morgan. “If we think about Martian rivers, we have to start thinking about it on a completely different scale than we did before.”

Hot and humid
Today Mars is cold and dry, but that was different a long time ago, research has shown. Billions of years ago, the planet would have had a much thicker atmosphere and therefore would have been not only a lot warmer, but also a lot more humid. Mars rover Curiosity previously discovered that Mars must have had shallow rivers and even lakes at that time. However, Perseverance now reveals that Mars must have had deep and fast-flowing rivers simultaneously.

Scientists are very interested in the warm and wet period of Mars’ existence. Not in the least, because the planet may have been a lot more livable then than it is now. Through the observations of the Mars rovers, among others, they have been trying for years to get a better grip on how long that wet and warm period lasted, how and why it came to an end.