The genetic heritage of late accretion to the Earth-Moon system

Isotopic investigation of the materials impacting the terrestrial planets after their formation
 

The origin and nature of the building blocks of the terrestrial planets may have changed during accretion. Identifying the source of the late accretion – that is the material added to the planets after their main phase of accretion – is of particular interest, since this material determines the planets’ final physico-chemical setup and later evolution. For example, it has been proposed that the habitability of the Earth is the result of a volatile-rich late accretion of outer solar system material. However, other lines of evidence suggest that the late accretion to Earth mainly stem from inner solar system sources and therefore contributed only little to its volatile element budget.

Using a large variety of impact rocks from the Moon and asteroids as witness plates of the late accretion in the inner solar system this PhD project will address the nature and origin of the late accretion using a novel isotopic tracer. The PhD student will conduct high-precision isotopic analyses of planetary samples from asteroids, Moon, and the Earth, making use of our new in-house state-of-the-art wet chemistry clean-rooms and mass-spectrometer facilities. Previous experience in isotope geo-/cosmochemistry is desirable.