Comparing a Star to its Planets: A Story of Light Stable Isotopes in the Solar System
The NASA Genesis mission returned samples of solar wind to Earth a little over a decade ago. Analyses of those samples have shown that the terrestrial planets are significantly enriched in the minor stable isotopes of N and O relative to the Sun. Genesis has not yet reported C isotope values for solar wind, but we recently completed analysis of infrared absorption by isotopes of CO (carbon monoxide) in the solar atmosphere. We find that the terrestrial planets are also enriched in the minor isotope of C relative to the Sun. Assuming that the Sun is representative of the bulk material from which the solar system formed, some process acted to enrich the terrestrial planets in the minor isotopes. I will describe the 3 main processes that have been proposed, and give the implications of each for solar system formation.