Meteorites

Sites
  • Views of the Solar System: Meteorites This is a commercial site by Calvin J. Hamilton. Many of the images are public domain. CJH has done a good job of assembling some of NASA's best images---many of which are hard to find at NASA's own sites. Images

    1. ./meteorite_001_iron.gif An iron meteorite from Derrick Peak, Antarctica.

      Iron meteorites (IRONS) are primarily iron and nickel.

      IRONS are probably remnants of the broken-up core of a chemically differentiated asteroids.

      IRONS constitute about 66 % of FINDS: i.e., meteorites just found on the ground without being seen to fall.

      But they are only about 6 % of FALLS: i.e., meteorites that are seen to fall and then are located. Most FALLS are STONES or STONY-IRONS.

        Question: Why are IRONS so much more abundant as FINDS than as FALLS?

        1. Just by chance.
        2. STONES and STONY-IRONS look pretty much like stones, and so don't catch the eye. IRONS look weird.

        Answer 2 is right.

        Given the 66 % to 6 %, most FINDS are IRONS by more than chance alone.

        IRONS are pretty resistant to burning up in the atmosphere, and so they the large abundance that we find on Earth is probably a biased sample of meteoroids.

        Iron meteoroids are probably a small fraction of meteoroids.

      See Se-554.

      Credit: NASA/JPL; download site Views of the Solar System: Meteorites.