Curiosity rover spies odd-looking metal meteorite on Mars
NASA’s Curiosity Mars rover recently examined an odd-looking golf-ball-sized rock on the Martian surface, confirming that it is an iron-nickel meteorite. This type of space rock is commonly found on Earth and previous examples have been seen on Mars, but this is the first one to be studied using Curiosity’s laser-firing Chemistry and Camera instrument (ChemCam).
The oddly shaped rock, dubbed “Egg Rock” by scientists, was first noticed by Curiosity’s Mast Camera (Mastcam) at a site the rover reached on October 27.
“The dark, smooth and lustrous aspect of this target, and its sort of spherical shape attracted the attention of some MSL scientists when we received the Mastcam images at the new location,” said ChemCam team member Pierre-Yves Meslin, via a release issued by the space agency.
The ChemCam instrument found iron, nickel, and phosphorus, plus other elements in concentrations that are still being determined. High concentrations of both nickel and phosphorous in some of the same locations on the meteorite suggests the presence of an iron-nickel-phosphide mineral that is rarely found except in iron-nickel meteorites.
Iron meteorites originate from the fragmented core material of large, ancient asteroids or protoplanets that had been shattered by catastrophic impacts. In the early history of the Solar System, those protoplanets had undergone melting during their formation which resulted in the molten metal fraction of a protoplanet to sink to its center – a process known as planetary differentiation – and forming an iron core.
“Iron meteorites provide records of many different asteroids that broke up, with fragments of their cores ending up on Earth and on Mars,” said ChemCam team member Horton Newsom of the University of New Mexico, Albuquerque. “Mars may have sampled a different population of asteroids than Earth has.”
The study of iron meteorites found on Mars can also provide information about how they have been affected by the Martian environment, in comparison to how Earth’s environment affects iron meteorites. Scientists will be analyzing ChemCam data from the first few laser shots each target on “Egg Rock” and comparing them with data from subsequent shots at the same spot to compare surface and interior chemistry.
The meteorite was found along Curiosity’s path up a layer of lower Mount sharp called the Murray formation. The sedimentary rocks of this region hold records of ancient lakebed environments that once existed on Mars. The rover’s second extended mission, which began last month, is to determine how ancient conditions at this location changed over time.
While Curiosity remains in good condition after working more than twice as long as its originally planned prime mission of about 23 months, two of its 10 scientific instruments are showing signs of potentially reduced capability.
The neutron-generating component of the rover’s Dynamic Albedo of Neutrons (DAN) instrument is returning data indicating reduced voltage. Even if DAN could no longer produce neutrons, the instrument could continue to check for water molecules in the ground using its passive mode.There also have been changes in the performance of the wind-sensing capability of Curiosity’s Rover Environmental Monitoring Station (REMS) instrument. REMS is still returning other Mars-weather data including temperatures, humidity, and pressure.
The Curiosity team is continuing to analyze data from both DAN and REMS to diagnosis the source of these performance changes.
Curiosity was launched on November 26, 2011, atop an Atlas V 541 variant booster from Cape Canaveral Air Force Station’s Space Launch Complex 41 in Florida. It landed inside Gale Crater, near the foot of Mount Sharp, on August 6, 2012.
Jim Sharkey is a lab assistant, writer and general science enthusiast who grew up in Enid, Oklahoma, the hometown of Skylab and Shuttle astronaut Owen K. Garriott. As a young Star Trek fan he participated in the letter-writing campaign which resulted in the space shuttle prototype being named Enterprise. While his academic studies have ranged from psychology and archaeology to biology, he has never lost his passion for space exploration. Jim began blogging about science, science fiction and futurism in 2004. Jim resides in the San Francisco Bay area and has attended NASA Socials for the Mars Science Laboratory Curiosity rover landing and the NASA LADEE lunar orbiter launch.