Talk:Heat Shield Rock

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"Meridiani Planum, the part of Mars where this meteorite was found, is suspected to have once been covered by a layer of material with a thickness of as much as 1 km which has been subsequently eroded. This means that on impact this meteorite might have created a crater, but evidence of that crater may have been subsequently erased by millions, or even billions, of years of erosion. In any case, the meteorite does not show much signs of rust despite Mars's oxidizing environment, so it either fell recently or was buried until recently. It also shows little signs of weathering or exposure to water."

It seems contradictory that the meteorite's crater took "millions, or even billions, of years" to erase yet the meteorite "fell recently". Buried I could understand if the meteor created a crater and was simultaneously buried, becoming unearthed recently by coincidence. Am I misinterpreting the text? blahpers 21:08, 2005 Jan 21 (UTC)

It either fell recently or was buried until recently. We have no way to tell. It might have fallen recently, but been slowed down sufficiently by Mars's atmosphere that it didn't make much of a crater when it fell. Since this is the first meteorite ever discovered on Mars (or anywhere outside of Earth), we don't really know much. Opportunity will look for more meteorites, it's on a dry featureless plain, and that's the sort of desert environment where meteorites are most readily spotted on Earth. -- Curps 21:54, 21 Jan 2005 (UTC)

[edit] is it iron?

Is it an iron meteorite? The article seems to make tangential mention of this when talking about drilling, but it's never clearly stated. Deuar 18:49, 18 March 2006 (UTC)

Good question. I'm guessing that no one knows for sure. And apparently the only way to find out for sure is to drill into it, which (if it is iron) would permanently damage the drilling tools. So I guess someone decided that drilling into all the *other* rocks had a higher priority. Still, it would be nice to have someone confirm or deny these guesses -- someone who actually understands the drilling protocol. --70.189.73.224 23:15, 5 October 2006 (UTC)

I think the answer is yes. NASA's Mars Exploration Rover Opportunity has found an iron meteorite on Mars, the first meteorite of any type ever identified on another planet. The pitted, basketball-size object is mostly made of iron and nickel. Readings from spectrometers on the rover determined that composition. (from http://photojournal.jpl.nasa.gov/catalog/PIA07269) No drilling needed. —dto (talkcontribs) 06:50, 6 October 2006 (UTC)

Yea, the rover stuck the Mossbauer Spectrometer up to the rock and they determined its composition from that. -- Riffsyphon1024 22:20, 6 October 2006 (UTC)

[1] gives a composition of the meteorite of mostly iron with nickle concentration between 5% (Mössbauer) and 7% APXS. The mössbauer identifies kamacite as alloy. --Stone 12:12, 22 May 2007 (UTC)

[edit] No meteorites on moon? / first on another solar system body?

I quote the article http://en.wikipedia.org/wiki/Meteorite : "More generally, a meteorite on the surface of any celestial body is an object that has come from elsewhere in space. Meteorites have been found on the Moon[1][2] and Mars.[3]" And the first reference is : "McSween, H.Y. Jr. (1976) A new type of chondritic meteorite found in lunar soil. Earth and Planetary Science Letters 31, 193-199". Unless the Moon doesn't count as a solar system body, both claims seem incorrect --84.58.30.117 18 November 2006