PERSEVERANCE ROVER FINDS EVIDENCE OF ANCIENT ASTEROID IMPACTS ON MARS

NASA's Perseverance rover has identified evidence that a 245-foot-thick stack of ancient rock on the rim of Jezero Crater was formed by repeated asteroid impacts over billions of years. The layered bedrock, termed the "Broom Point member" by the rover's science team, is believed to be more than 3.9 billion years old, making it among the oldest terrain examined by a Mars rover to date. The findings were published in the Journal of Geophysical Research: Planets on Wednesday and provide insight into a particularly active period in the early solar system's history.

After ascending the western rim of Jezero Crater in late 2024, Perseverance examined the surrounding geological formations using its on-board science instruments. The rover's analysis revealed six distinct rock types at Broom Point, including breccias—rocks composed of angular fragments—alternating with layers of fine-grained, pulverised rock dust. Rock fragments within the breccias contained gas-bubble cavities, indicating the material had once been molten. Tiny, dark, glassy beads discovered within the layers provided a crucial indicator of formation mechanism; whilst volcanoes produce similar glassy droplets, the high abundance of such beads at this site points to asteroid impacts as the primary cause.

Ken Farley, Perseverance deputy project scientist at Caltech, stated that Mars's lack of plate tectonics has preserved this ancient geological record intact, unlike Earth's earliest history, which has been fundamentally altered and erased by tectonic activity. The Broom Point member thus offers a rare window into a geological period that no longer exists on Earth. Perseverance has also reached a separate milestone, completing the equivalent of a full marathon—26.2 miles—across the Martian surface after five years and four months of driving.