NASA’s Perseverance rover has been studying Jezero Crater for the past two years and suggests it once contained an ancient lake. Satellite images and mineral analysis confirmed this prediction, but now we have it. Data from the rover’s ground-based radar shows that the crater we see today is the result of years-long cycles of erosion and sediment accumulation.

Perseverance; It is equipped with numerous scientific instruments, including spectrometers, weather sensors and numerous cameras. It is also equipped with the Radar Imager for Mars (RIMFAX) underground experiment, which can detect subsurface geological features at depths of up to 20 meters. “Some geologists say radar’s ability to see below the surface is something of a hoax,” said lead author David Page of the University of California, Los Angeles.

As Perseverance rolled across the floor or crater of Jezero, RIMFAX fired radar pulses in 10-centimeter increments. A team from UCLA and the University of Oslo spent years testing RIMFAX on Earth, and it showed results; The data shows regular horizontal layers of sediment seen at the bottom of a lake on Earth.

Researchers say this is the first evidence that Jezero Crater was indeed a lake in the distant past. RIMFAX detected two periods when flowing water deposited sediment in the crater. The last of two changes in lake level allowed the delta to extend deeper into the crater. These rainy periods are associated with two periods of erosion, including the period that eroded the larger delta into the delta we see today.

RIMFAX ground-penetrating radar measurements in the Cape Nukshak area. Image Credit: Svein-Erik Hamran, Thor Berger, David Page, University of Oslo/UCLA/California Jet Propulsion Laboratory/NASA

Confirmation of the lake’s water history increases interest in Perseverance rock samples. As the rover explores the surface, it completes the first phase of NASA’s ambitious mission to send samples to Mars. The rover’s unique sample caching system has already collected 23 cores, and NASA has established a sample repository from which future phases of the mission can collect sample samples. However, NASA has been criticized for mismanagement and unrealistic goals of the sample return campaign. The mission is currently suspended as we wait for an updated plan.

Perseverance reached Mars in February 2021, building on the success of NASA’s Curiosity rover. It deployed the Ingenuity Mars helicopter to demonstrate the technology, but the impressive drone failed just last week. Perseverance is now alone, without an air spotter to guide its way. With all this, Curiosity made history even without a flying satellite. Determination is increasing, and studying Martian geology with RIMFAX and other instruments is likely years away.