Simulations Reveal Giant Impacts May Destroy, Not Create, Moons' Oceans
New simulations suggest that massive collisions between icy moons do not reliably create subsurface oceans and may instead cause smaller moons to lose existing ones. While impacts generate significant heat, the resulting fragmentation allows rapid heat loss, and the reassembly process removes insulating internal structures. Larger moons may retain or deepen pre-existing oceans, but no new oceans were formed in frozen bodies during the tested scenarios.