Giant impacts can strip subsurface oceans from small icy moons, study finds

Southwest Research Institute (SwRI) scientists have used computer simulations to assess how disruptive impacts influence icy moons that host subsurface oceans, a study reported in the latest issue of *Nature Astronomy*. The research examined the effects of collisions ranging from small meteoroids to large asteroids on moons such as Europa, Enceladus, Ganymede and Titan, modeling how impact‑generated heat, fracturing and ice loss could alter the thermal and structural conditions that sustain liquid water beneath thick ice shells.

The simulations indicate that while impact events can modify the thickness of the ice crust, redistribute heat, and in some cases accelerate the loss of existing oceans, they do not appear capable of generating new subsurface oceans on moons that lack them. These findings refine our understanding of the long‑term stability of oceanic environments in the outer solar system and provide constraints for future missions seeking signs of habitability on these worlds.