It has been a trying time for NASA, what with astronauts suspended in space and an order to shut down its diversity programs. But there is good news coming from the small Mars rover Curiosity. A new study using imagery from the rover shows evidence that the red planet once may have been pretty hospitable, even habitable.

The study by scientists at Caltech discusses the discovery of ancient wave ripples on the Mars surface, first found by the Curiosity rover in 2022. Scientists say these ripples are "undulations in the sandy shores of lakebeds, created as wind-driven water laps back and forth." In other words, Mars had a warm body of water, open to the air and not covered by ice, supporting the possibility that there was in fact life on Mars.

"The team estimates that the ripples formed around 3.7 billion years ago, indicating that the Martian atmosphere and climate must have been warm and dense enough to support liquid water open to the air at the time," read a Caltech report Jan. 15. The study, led by Caltech professors John Grotzinger and Michael Lamb, appears in the journal Science Advances.

While Mars is now a desert planet that's 1,000 times drier than any Earth desert, there has been mounting evidence that the red planet once held water and could potentially support microbes, according to reports. Scientists pinpoint the formation of the ripples—about 6 millimeters high and 4-5 centimeters apart, and likely from a shallow lake of no more than 2 meters deep—to a time when the planet was becoming drier.

"Extending the length of time that liquid water was present extends the possibilities for microbial habitability later into Mars's history," said Claire Mondro, the first author of the study and a postdoc at Caltech.

Curiosity has been patrolling the surface of Mars for the last 13 years, searching for signs of ancient microbial life on the planet. Last year, the Curiosity rover basically fell into a discovery of sulfur on Mars.

"Finding a field of stones made of pure sulfur is like finding an oasis in the desert," said Ashwin Vasavada, Curiosity project scientist, in a statement at the time. "It shouldn't be there, so now we have to explain it. Discovering strange and unexpected things is what makes planetary exploration so exciting."

Less than two weeks ago, Curiosity found what appeared to be massive kidney beans on Mars, but were actually frozen sand dunes.