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Assume you have a small sliver of a lunar or martian meteorite (or an object asserted to be so).

Without using any special scientific equipment, is it possible to verify (or give a high probability) that it is indeed of lunar or martian origin?

Are there any visual or other tests one can do to confirm the source?

(If this question is off-topic or not quite right, feel free to close.)

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One could make the argument that this is off topic, but I think it just barely squeaks into the edge of being on topic for astronomy. (It would have been far off topic on Physics before the merge.) But if other people generally think this is off topic here now, I'll defer to that opinion. (BTW Anna, you certainly haven't done anything wrong! It's a good question, this may just not be the place for it.) –  David Z May 6 '12 at 5:05
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The short answer is no.

Martian and Lunar meteorites look just like Earth rocks as they come from the surface of the Moon and Mars and so are very similar in compositions. The only way I know of to confirm that they are not of earthly origin is to analyze a sample with a mass spectrometer and look for signatures that their composition is different. There are slight differences between rocks from the various locations but they are not something that can seen without specialized equipment.

There are only three ways that I know of to be sure a supposed meteorite is of cosmic origin.

  1. It looks like this:

    enter image description here (This image came from Wikipedia here) The iron crystals you see can only be formed by cooling very slowly in a microgravity environment. Thus they cannot form on Earth. If you have a rock that looks like this on the inside, it is 100% a meteorite.

  2. You watch it blaze through the sky and see it land. If this happened you could be pretty sure it was of cosmic origin. I don't know of anyone who has found a meteorite but there is one recorded case a woman getting hit by one and another of where one landed in the trunk of someone's car. In neither case was it actually observed flying through the sky though.

  3. You find a rock lying in the ice fields of Antarctica. My wife has a friend that makes periodic trips down to Antarctica for this specific reason. If you find rocks on these mile deep ice fields, you can be almost 100% sure that they fell from the sky.

That said, you still only know that they came from space. To determine the exact (or at least a more exact) location you need specialized tools.

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The absolute best way, and really the only way, is to do a mass spectroscopy of the sample. There are labs which will perform spectral analysis on a sample, contact your local university's chemistry department, who could either perform the test or let you know who might be able to. This will tell you the following:

  1. What is the chemical makeup of the device.
  2. What are the percentages of various isotopes of each atom.

Generally speaking, it's the latter which allows one to identify where it came from.

Aside from that, there's a few other tests.

The article "How to identify a meteorite" tells you some stuff that's specific to meteorites, but there is one that will hold true for rocks from other locations. There should be a small black film around the object, that can't be explained by normal reasoning. This isn't proof alone, a fire can produce said black film, but it's enough to make one suspicious. It's also very common for meteorites to be magnetic (Often leaving poor grad students to drag heavy magnets for miles searching for possible meteorites)

But all of these ancillary methods will only give one a way to give a first pass. The best method is as mentioned at the beginning.

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