basaltic meteorites

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basaltic meteorites Achondrite meteorites that have been derived from parent bodies sufficiently evolved to have acquired a basaltic crust (in contrast, for example, to chondrites, which have derived from relatively primitive bodies). Eucrites and howardites (similar to eucrites, but more pyroxene-rich) probably formed through magmatic processes on the same parent body (possibly the Moon) around 4.5 billion years ago. The shergottyite—nakhlite—chassignite class of basaltic meteorite has a distinctly different oxygen-isotope composition (see OXYGEN-ISOTOPE RATIO), volatile content, and age (around 1.3 billion years), and originated from a separate parent body, probably the planet Mars.