NASA’s Perseverance rover has discovered evidence of an ancient lake on Mars that may have once contained traces of past life. The rover’s discovery in Crater Lake confirmed the existence of ancient lake sediments and provided new hopes for finding organic remains and confirming life on Mars.

On February 18, 2021, Perseverance successfully landed inside the 45-kilometer-diameter crater Lake. Scientists suggest that there may have been a lake and river delta here millions or even tens of millions of years ago. However, the exact time frame for the presence of water on Mars remains a subject of active research and debate among scientists. The rover’s purpose is to study the crater and look for signs of previous life, as well as collect samples for future analysis on Earth.

Using the rover’s RIMFAX (Radar Imager for Mars Underground Experiment) instrument, scientists from the University of California and Oslo learned new details about how sedimentary rock deposits formed at the bottom of the crater. Research has revealed the presence of sedimentary rocks in the crater, indicating that water once existed. This raises the possibility of microbial life on Mars, and if this is indeed the case, sedimentary rock samples from the crater floor may contain traces of its existence.

“We can see different deposits from orbit, but we need to look below the surface to understand how they form,” explains RIMFAX deputy principal investigator and UCLA professor David Page.

The rover uses RIMFAX radar to send waves at 10-centimeter intervals to a depth of about 20 meters. This allows you to create a profile of subsurface layers and reveal details of sediment formation.

The data show that sediments at the bottom of the crater formed in two periods, resulting in horizontal layers that resemble typical layered rock formations on Earth. Fluctuations in the lake’s water level led to the formation of a large-scale delta, which Perseverance successfully crossed between May and December 2022.

Radiometric measurements also showed an irregular crater floor beneath the delta; This shows that the rocks were eroded before collapsing. The dried lake provided the conditions for the erosion of sedimentary layers that formed the characteristic geological formations we see on Mars today.

“We see preserved changes in sedimentary rocks associated with global changes on Mars. It is incredible that so much evidence can be observed in a relatively small geographical area, and this allows us to summarize the data and use it to obtain a broad overview of Crater Lake,” emphasizes David Page.