NASA's Perseverance rover has discovered an unusual rock on Mars. It could be an iron-nickel meteorite, according to mission team scientists, reports the website „Mashable“, quoted by NOVA.
The oddly shaped rock is over 75 cm in size and has caught the attention of researchers because it rises above the surrounding flat and cracked terrain. The rover selected it for a more detailed study while working outside the Jezero Crater — a river basin that Perseverance has been exploring since its landing in 2021.
The rover photographed the rock on September 2 and September 19. But the public is only now learning about the find. The extended federal government shutdown has delayed routine announcements from the U.S. space agency, and NASA did not release details of the discovery along with other mission news until Nov. 13.
If confirmed as a meteorite, Phippsaksla, as scientists have dubbed the rock, would be the first of its kind for Perseverance. The Mars rover Curiosity has already cataloged several metal-rich meteorites in Gale Crater, about 2,000 miles away, and earlier rovers Opportunity and Spirit have also found such alien rocks. Their absence from Perseverance's route has puzzled mission scientists.
„It was somewhat unexpected that Perseverance did not see iron-nickel meteorites in Jezero Crater. "Especially given the similar age to Gale Crater and the numerous smaller impact craters, which suggest that meteorites have fallen on the floor, delta, and rim of the crater over time," said Candice Bedford, a researcher at Purdue University.
Initial data from Perseverance's SuperCam instrument shows high levels of iron and nickel, a combination typical of meteorites originating from the interior of large asteroids. Chemical signatures suggest that the rock was formed elsewhere before hitting Mars.
Meteorites are common in the solar system but harder to detect on Earth. Scientists estimate that about 48.5 tons of such fragments reach the planet every day, with most burning up in the atmosphere or falling into the oceans. Only about 60,000 meteorites have been identified on Earth to date.
Most known meteorites come from asteroids, but a small number originate from the Moon or Mars. At least 175 Martian meteorites have been found on Earth — all are igneous rocks that once crystallized from molten rock.
On Mars itself, iron-nickel meteorites often survive well in the thin atmosphere and harsh environment. Since 2005, the International Meteorite Society has officially recognized 15 meteorites found by Mars rovers. Curiosity's 2023 discovery — a rock about 30 cm wide, called "Cacao" — is the first of its kind in the world. is not yet among them.
Scientists believe that iron meteorites may be better able to resist erosion on Mars, which could explain why some appear to be sitting on flat surfaces rather than in craters. In other cases, the crater may have worn away completely, leaving only the rock.
Perseverance is currently working on an old bedrock crater marked by ancient impacts outside Jezero Crater — a place where meteorites may be more common. The researchers plan further analysis to determine the origin of Phippsaksla.
“If this rock is determined to be a meteorite,“ Bedford writes, “Perseverance could finally join the list of rovers that have examined fragments of space “visitors“ on Mars.“