The origin of the Moon's Earth-like tungsten isotopic composition from dynamical and geochemical modeling.

ABSTRACT: The Earth and Moon have identical or very similar isotopic compositions for many elements, including tungsten. However, canonical models of the Moon-forming impact predict that the Moon should be made mostly of material from the impactor, Theia. Here we evaluate the probability of the Moon inheriting its Earth-like tungsten isotopes from Theia in the canonical giant impact scenario, using 242 N-body models of planetary accretion and tracking tungsten isotopic evolution, and find that this probability is <1.6-4.7%. Mixing in up to 30% terrestrial materials increases this probability, but it remains <10%. Achieving similarity in stable isotopes is also a low-probability outcome, and is controlled by different mechanisms than tungsten. The Moon's stable isotopes and tungsten isotopic composit

SUBMITTER: Fischer RA 

PROVIDER: S-EPMC7782809 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature