Curiosity Finds Large Iron Meteorite on Mars
NASA/JPL-Caltech (edit by Jason Major/LightsInTheDark.com)
NASA's rover Curiosity has begun drilling operations for the third time on Mars. Currently located at a geologically interesting location nicknamed "The Kimberley," the one-ton rover also took the opportunity to photograph itself and the surrounding landscape in some stunning Martian "selfies." In this scene, Curiosity appears to be leaning its "head" -- a suite of instruments including the Chemcam (the laser "eye") and Mastcam cameras -- to the side, capturing the 5 kilometer-high Aeolis Mons (a.k.a. "Mount Sharp") on the horizon. The self portrait has been stitched togetherby Discovery News' Jason Major
from a series of raw photographs (taken on sol 613, April 28, of the mission) by Curiosity's robotic arm-mounted Mars Hand Lens Imager (MAHLI) instrument.
NASA/JPL-Caltech (edit by Doug Ellison/JPL)
In this scene, Curiosity appears to be concentrating hard on a rock of interest -- dubbed "Windjana" by mission scientists after a gorge in Western Australia -- that it has cleaned with its robotic arm-mounted Dust Abrasion Tool. A grey circular patch can be seen on the otherwise rusty rock's surface where the tool has scrubbed away any surface dust ready for analysis and drilling. This beautiful selfie was createdby JPL's Doug Ellison
, after assembling a collection of photos from the rover's Mars Hand Lens Imager (MAHLI) on sol 613 (April 28) of the mission. Curiosity's selfies not only produce some breathtaking scenes, they are also used by mission engineers to keep tabs on the condition of the rover the more time it is exposed to the harsh Martian environment.
Curiosity used its Mastcam to photograph this closeup of its Rock Abrasion Tool. The instrument spins the wire-bristle brush over rock surfaces to remove layers of dust that has accumulated.
After brushing, a grey circle of rock beneath the ruddy Mars dust is exposed for further analysis. In this photo by Curiosity's Mars Hand Lens Imager (MAHLI), the texture of Mars dust is obvious and fine cracks or seams in "Windjana" can be seen. "In the brushed spot, we can see that the rock is fine-grained, its true color is much grayer than the surface dust, and some portions of the rock are harder than others, creating the interesting bumpy textures,"said Melissa Rice
, Curiosity science team member, of the California Institute of Technology, Pasadena. "All of these traits reinforce our interest in drilling here in order understand the chemistry of the fluids that bound these grains together to form the rock."
On April 29, Curiosity used its drill to bore a 2 centimeter hole into Windjana. This is only the third rock Curiosity has drilled into since landing on the red planet on Aug. 5, 2012. The grey color obviously extends deeper into the rock than just on its surface, and the powder created can provide a pristine rock sample for further analysis, helping mission scientists understand how the rock formed and under what environmental conditions.
The first two drilled rocks were located in Yellowknife Bay, approximately 4 kilometers from The Kimberley. Those rocks were determined to be mudstone slabs formed through water action and sediment, providing compelling evidence that the interior of Gale Crater used to play host to a lakebed and may have provided a habitable environment for ancient microbial life. This new drilling operation will provide more clues as to how rock formed in the region, revealing more tantalizing clues as to the past habitability of the red planet.
On Curiosity’s 640th day (or sol) on Mars, as it continued its long drive to the base of Aeolis Mons (a.k.a. Mount Sharp), the robot stumbled across a fairly hefty meteorite. Shown here, the 2-meter-wide iron space rock can be seen embedded in the ruddy regolith.
The May 25 find adds to the puzzling reasons as to why the majority of meteorites found on the Martian surface are iron rich. On Earth, though fairly common, iron-rich meteorites are outnumbered by stony ones, leading scientists to believe that large iron-rich specimens may be more resistant to Martian erosion processes than stony space rocks.
This large meteorite appears to consist of two separate components dubbed “Lebanon” (the larger meteorite) and “Lebanon B” (the smaller one in the foreground) by Curiosity’s mission scientists.
Curiosity spent some time photographing and analyzing the meteorite with its Remote Micro-Imager (RMI), a component of the mission’s Chemistry and Camera (ChemCam) instrument. The RMI images are the circular inserts in the image above. The rover’s Mastcam instrument also imaged the area, adding color and context to the observation.
Like other iron meteorites observed by Curiosity, and NASA’s Mars Exploration Rovers Opportunity and Spirit, this example is riddled with pockmarks and cavities. According to a NASA news release, these features may be caused by “preferential erosion along crystalline boundaries within the metal of the rock.” It’s also possible that the cavities used to contain olivine crystals — often found in a rare type of stony-iron meteorites called pallasites. The olivine would have long since eroded away, leaving the iron behind.