Not all fractures at Occator Crater are the same


The bright spots in the Occator crater on asteroid 1 Ceres are fresh deposits of salt minerals, thought to have formed by relatively recent “eruptions” of salty slush. The biggest bright spot is around a central pit, and the other spots are associated with fractures across the crater’s floor. Debra Buczkowski and colleagues studied those fractures to understand how the ‘slush eruptions’ might have formed. Many of the fractures are concentric with the crater (and the central pit), and so probably are related to the crater’s impact formation. Other fractures, though, radiate from a spot on the SW wall of Occator, a site of no particular significance for the crater’s impact origin. Buczkowski’s group suggests that these fractures formed above a growing dome in the floor of Occator (something like the cracks on the top of a rising loaf of bread). The cause of the dome was likely an injection of salty slush, rising from Ceres’ mantle. This injected slush could likely have also erupted, and then dried in the vacuum of space to leave behind the bright salt deposits.

More information