A new type of solar system material recovered from Ordovician marine limestone
From mid Ordovician ~470 Myr old limestone >100 fossil L chondritic meteorites have been recovered, representing the markedly enhanced flux of meteorites to Earth following the breakup of the L chondrite parent body. Recently one anomalous meteorite, Osterplana 065 (Ost 65) was found in the same beds that yield L chondrites. The cosmic ray exposure age of Ost 65 shows that it may be a fragment of the impactor that broke up the L chondrite parent body. Here we show that in a chromium versus oxygen isotope plot Ost 65 falls outside all fields encompassing the known meteorite types. This may be the first documented example of an 'extinct' meteorite, that is, a meteorite type that does not fall on Earth today because its parent body has been consumed by collisions. The meteorites found on Earth today apparently do not give a full representation of the kind of bodies in the asteroid belt ~500 Myr ago.
Nature communications