Pairing
Pairing is recognising that meteorites recovered and named separately are actually pieces of the same fall.
A meteoroid often breaks up in the atmosphere, scattering many fragments over a strewn field. In deserts or Antarctica, these pieces may be picked up years apart and submitted separately, each with its own name or number. When researchers conclude they belong together, the meteorites are said to be paired.
Pairing is judged from several lines of evidence. The meteorites should have the same classification and closely matching mineral compositions, similar shock and weathering, compatible find locations, and ideally matching cosmic-ray exposure ages and terrestrial ages. Oxygen isotopes help with achondrites. No single test is conclusive, so pairings are sometimes revised.
Pairing matters because counting fragments as separate falls would distort statistics, such as how common each meteorite type is or how many meteorites land per square kilometre. It also lets scientists combine data from different pieces into one picture. The martian breccia NWA 7034 has several paired stones, including NWA 7533. For collectors, a pairing note in the official records explains why specimens with different numbers may be the same meteorite. Pairing cannot be decided by eye alone, even when pieces look identical.
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