The Breakup of a Meteorite Parent Body and the Delivery of Meteorites to Earth
by Benoit, P. H.; Sears, D. W. G.
Whether many of the 10,000 meteorites collected in the Antarctic are unlike those falling elsewhere is contentious. The Antarctic H chondrites, one of the major classes of stony meteorites, include a number of individuals with higher induced thermoluminescence peak temperatures than observed among non-Antarctic H chondrites. The proportion of such individuals decreases with the mean terrestrial age of the meteorites at the various ice fields. These H chondrites have cosmic-ray exposure ages of about 8 million years, experienced little cosmic-ray shielding, and suffered rapid postmetamorphic cooling. Breakup of the H chondrite parent body, 8 million years ago, may have produced two types of material with different size distributions and thermal histories. The smaller objects reached Earth more rapidly through more rapid orbital evolution.
- Journal
- Science
- Volume
- 255
- Issue
- 5052
- Year
- 1992
- Start Page
- 1685-1687
- URL
- https://dx.doi.org/10.1126/science.255.5052.1685
- ISBN/ISSN
- 1095-9203; 0036-8075
- DOI
- 10.1126/science.255.5052.1685