Abstract

High-precision oxygen isotope analysis has proved to be a powerful technique for investigating early Solar System processes. In particular, oxygen isotopic mass-independent variation measured in meteorites and their components probably reflects differences that were acquired as a result of UV photo-dissociation of CO in the precursor giant molecular cloud from which the Solar System formed. Oxygen isotopes provide a powerful means of assessing the extent to which early-formed asteroids underwent melting and homogenisation, with chondrites and primitive achondrites showing high levels of heterogeneity, whereas differentiated achondrites show only minimal variation. Oxygen isotopes are an essential tool in fingerprinting different groups of meteorites and have played a central role in understanding the nature of the Moon-forming giant impact. High-precision oxygen isotope analysis is likely to be an important analytical technique in the study of samples returned from primitive asteroids by the Japanese spacecraft Hayabusa2 later this year and by the NASA OSIRIS -REx mission in 2023.