Material in rare meteorites may pre‐date solar system

The discovery of anomalously high proportions of oxygen 16 in certain rare meteorites has led to speculation that these meteorites may contain remnants of material with a separate nucleosynthetic history from the bulk of the solar system. This material appears to be present in meteoritic inclusions that have been analyzed by Robert N. Clayton, Lawrence Grossman and Toshiko K. Mayeda, all geochemists at the University of Chicago, and may represent interstellar dust grains that somehow survived the formation of the solar system without being vaporized or homogenized.