For decades, the standard perception of Mars has been almost black-and-white in its simplicity—or rather red and blue: There is the barren, freeze-dried and rust-ruddy planet of today. And eons ago, there was a world warmer, wetter and more aquamarine with rivers, lakes, oceans and perhaps even life on its surface. 

Scientists surveyed the landing site of NASA’s Perseverance rover, which touched down in Jezero Crater in February. Mission planners chose Jezero because orbital images suggested it harbors an ancient river delta and lake system sculpted by flowing water billions of years ago. Now analysis from Perseverance has not only confirmed this to be true but has also discovered short-lived episodes of sudden change that happened there.

Co-led by Nicolas Mangold of the University of Nantes in France, the study team used images taken by Perseverance to examine the size, orientation and distribution of rocks strewn around the rover and embedded in sedimentary layers on exposed cliff faces and outcrops up to several kilometers away. The results show that 3.7 billion years ago, a river did indeed flow into this region at speeds of several meters per second, feeding a lake that filled the 45-kilometer-wide crater to depths as great as 100 meters in places. 

What all this portends is nothing less than a new era in our otherworldly exploration. With each additional sign that Perseverance and other missions find of localized, transient events profoundly shaping parts of the Martian landscape, another colorful thread will be woven into the grand tapestry of the planet’s history. 

Source: Science

Photo: NASA