NASA’s Perseverance rover has made another intriguing find while exploring the rim of Jezero Crater on Mars: Skull Hill. As it continued its descent down a slope known as Witch Hazel Hill, the rover paused at a boundary between two types of exposed bedrock—one light, one dark. This contact zone, visible from orbit and named Port Anson, offers clues about Mars’ geologic history.
Meet Skull Hill
What really caught scientists’ attention was a dark, jagged rock nearby, dramatically standing out from its pale surroundings. Dubbed Skull Hill for its shape and color, this float rock (a rock transported from its original location) features small pits and even what appear to be tiny spherical structures, or spherules, embedded in the nearby soil.
Meteorite or something else?
At first glance, Skull Hill resembles meteorites previously found by the Curiosity rover in Gale Crater—especially with its dark surface and rough texture. On Earth, meteorites often contain high amounts of iron and nickel, and so do many of those discovered on Mars. But recent chemical data gathered by Perseverance’s SuperCam suggest that Skull Hill doesn’t match that profile.
An igneous origin?
Instead, scientists now think Skull Hill might be an igneous rock, possibly formed by ancient volcanic activity or thrown there during a violent meteor impact. Such rocks often contain iron and magnesium and are made up of minerals like olivine and pyroxene, which give them their darker colors.
Perseverance’s suite of scientific instruments will continue to analyze Skull Hill and other rocks like it, helping researchers piece together the complex story of Mars’ geologic past.
Source: NASA.
Image credit: NASA/JPL-Caltech/ASU.
