The rover collected samples for further analysis and search for signs of life
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 exploration of Jezero Crater has confirmed the presence of ancient lake sediments, providing new hope for the search for organic remains and confirmation of life on Mars.
February 18, 2021 Perseverance successfully landed inside the Jezero Crater, which has a diameter of 45 kilometers. Scientists suggest that millions or tens of millions of years ago a lake and river delta could have existed here. However, the exact time frame for the presence of water on Mars remains the subject of active research and debate among scientists. The rover's goal is to explore the crater and search for traces of previous life, as well as collect samples for future analysis on Earth.
Scientists from the University of California and Oslo have learned new details about how sediment deposits formed on the crater floor using the rover's RIMFAX (Radar Imager for Mars' Subsurface Experiment) instrument. Research has revealed the presence of sedimentary rocks indicating the presence of water that once was in the crater. This opens up the possibility of microbiological life on Mars, and if this is true, then sediment samples from the crater floor may contain traces of its existence.
«From orbit we can see various deposits, but to understand how they formed, we need to look below the surface», — explains David Page, RIMFAX Deputy Principal Investigator and UCLA Professor.
Using the RIMFAX radar, the rover sends waves to a depth of about 20 meters at intervals of 10 centimeters. This allows the profile of subsurface layers to be created and details of sediment formation to be revealed.
The data demonstrate that the sediments on the crater floor were deposited in two periods, resulting in horizontal layers reminiscent of typical layered rock formations on Earth. Fluctuations in the lake's water level led to the formation of a large delta, which Perseverance successfully crossed from May to December 2022.
Radiometric measurements also showed an uneven crater floor beneath the delta, indicating erosion of the rocks before sedimentation. The dry lake provided the conditions for the erosion of sedimentary layers, forming the characteristic geological formations we see on the surface of Mars today.
«We see changes preserved in sedimentary rocks that are associated with global changes on Mars. It's incredible that so much evidence can be observed in one relatively small geographic area, and this allows us to aggregate and use the data to provide a broad overview of the entire Jezero Crater— David Page emphasizes.