Analyses of a meteorite suggest that the interiors of large asteroids, such as Vesta, could have undergone dynamic, planet-like processes early in their history. The finding, reported online in Nature Geoscience this week, recasts these asteroids as geologically active bodies in the early Solar System.
Beverley Tkalcec and colleagues analysed mineral grains in a diogenite, a type of meteorite thought to represent a sample of Vesta - one of the largest asteroids in the Solar System. The orientation of the mineral grains suggests deformation in the asteroid at depth, similar to that experienced by rocks in the Earth’s upper mantle. The deformation proposed is consistent with models of Vesta’s evolution, which show solidified material sinking through a molten mantle as the asteroid cools.