Confirmation of Ancient Lake Sediments on Mars Through Rover Data
NASA’s Perseverance rover has successfully collected data affirming the presence of ancient lake sediments in Jezero Crater on Mars, as detailed in a study released on Friday. Ground-penetrating radar observations conducted by the robotic rover corroborate earlier orbital imagery, supporting the hypothesis that certain regions of Mars were once submerged in water, potentially fostering microbial life.
Published in the journal Science Advances, the research was led by teams from the University of California, Los Angeles (UCLA), and the University of Oslo. The study relies on subsurface scans conducted by the car-sized rover over several months in 2022 as it traversed from the crater floor to an adjacent area displaying braided, sedimentary-like features reminiscent of Earth’s river deltas when viewed from orbit.
Utilizing the rover’s RIMFAX radar instrument, scientists were able to examine rock layers up to 65 feet (20 meters) deep, offering a cross-sectional view akin to a road cut. The distinct layers provide compelling evidence of soil sediments transported by water and deposited in Jezero Crater and its delta by a river. This discovery aligns with longstanding suggestions that Mars, once cold, arid, and lifeless, may have had a warmer, wetter, and potentially habitable past.
Researchers anticipate a close examination of Jezero’s sediments, believed to have formed around 3 billion years ago, using samples collected by Perseverance for future transport to Earth. In the interim, the recent study serves as welcome validation for the scientists, affirming that their Mars exploration efforts were directed to the right location.
The study complements remote analyses of early core samples drilled by Perseverance at four sites near its landing site in February 2021. Unexpectedly, these samples revealed volcanic rock instead of the anticipated sedimentary composition. However, this divergence does not contradict the recent findings. Even the volcanic rocks exhibited signs of alteration due to water exposure, leading scientists to speculate that sedimentary deposits may have eroded over time.
The RIMFAX radar readings disclosed on Friday further indicate signs of erosion before and after the formation of sedimentary layers at the crater’s western edge. This underscores the complex geological history of the region, highlighting the significance of the mission’s location. According to UCLA planetary scientist David Paige, who authored the paper, the rover’s transition to the delta region is especially noteworthy as it reveals compelling evidence of lake sediments, a key objective for choosing this specific location on Mars.
