Meet the parents
Meteorites were once part of larger objects, or parent bodies, that formed when chondrules, calcium-aluminum inclusions (CAIs), dust grains and other components accreted, or stuck together. The chemical makeup of each meteorite depends in large part on how much of each of these ingredients was present when and where the parent body came together.
Scientists rely on detailed laboratory analysis to determine whether two meteorites came from the same parent body. One of the most common techniques is to look at the different forms, or isotopes, of oxygen present in a meteorite. Researchers have grouped meteorites into categories based on their oxygen-isotope "signatures". If two samples have the same signature, they probably came from the same parent body. In contrast, the three samples shown above and below appear similar but actually have quite different oxygen isotope signatures. As a result, scientists think these meteorites originated from three different parent bodies.
Topic: Earth Science
Keywords: Astrogeology, Astrophysics, Chemical elements, Chondrites (Meteorites), Chondrules, Mineralogy, Oxygen--Isotopes