Posted on 06/13/2006 3:28:15 PM PDT by blam
Mars rover Spirit finds metallic meteorites
13:00 13 June 2006
NewScientist.com news service
Maggie McKee
Allan Hills, one of the iron meteorites discovered by the Mars rover Spirit (right foreground), appears lighter and smoother than surrounding rocks (Image: NASA/JPL/Cornell)
Two iron meteorites have been spotted by the Mars rover Spirit, mission scientists have announced. The finds are the first meteorites identified by Spirit, although its twin, Opportunity, discovered a similar space rock on the other side of the planet in January 2005.
Spirit photographed the rocks in April 2006, just after it parked at Low Ridge Haven, a northern-tilting slope that is serving as its home for the six-month-long Martian winter.
The rocks appear smoother and lighter in tone than surrounding rocks. They resemble the glossy, pitted meteorite – dubbed "Heat Shield Rock" – that Opportunity found near its discarded heat shield.
Observations of that rock with Opportunity's miniature thermal emission spectrometer (Mini-TES) showed it was very reflective – a telltale sign of an iron meteorite (see Metal chunk on Mars confirmed as meteorite). Now, observations by the Mini-TES on Spirit reveal the two suspect rocks are similarly reflective.
"They're very good reflectors," says mission member Ray Arvidson of Washington University in St Louis, US. "We're seeing the heat of the sky being reflected to Mini-TES. I don't know how that can happen unless it's a metal."
Drive-by meteorite
Iron meteorites make up just a few percent of the space rocks that would be expected to litter the Martian surface. But their appearance and spectral properties make them much easier to identify than the more common "stony" meteorites.
The meteorites are fragments of larger space rocks nudged out of the asteroid belt between Mars and Jupiter and into the Red Planet's path. They survive on the surface because there are few geological processes on Mars that would bury them after they fall to ground, says Arvidson.
"It's not surprising that we occasionally drive past a meteorite," he told New Scientist. "Mars is a very old surface and the erosion rates are relatively small, so we should expect these things to collect and be exposed for our viewing."
Features observed at Spirit's winter haven are being named after research stations and place names in Antarctica. So the two rocks have been dubbed "Allan Hills" – for a site where many meteorites are found in the Antarctic ice – and Zhong Shan, an Antarctic base established by China in 1989.
Rove ???
Are they from Earth? They sent us some of their meteorites, and fair's fair.
The little rovers are still with us..
Little miracles, Spirit and Opportunity!
Keep on truckin'!
Boy, that Amelia Erhardt got WAY off course!
ping
Ahhh
Ping aling, Two Thirds.
Causing the global warming on Mars that parallels that on Earth, no doubt.
Sheesh.
This is also the same planet that has long been believed to possibly contain the same primordal slimes that evolve in to Democrats.
did they actually use those words? LOL
"This is also the same planet that has long been believed to possibly contain the same primordal slimes that evolve in to Democrats."
No, that was Uranus.
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