Brief
Study Finds Icy Moon Collisions Likely Preserve Subsurface Oceans
Simulations suggest that even after being shattered, icy moons can retain or regain liquid water beneath their crusts.
By Felo News Desk · Published
Scientists at the University of Maryland used computer simulations to examine whether massive collisions that break apart icy moons also destroy the oceans hidden beneath their icy shells. The study, published in Nature Astronomy, indicates that moons that possessed subsurface oceans before an impact are likely to retain them afterward.
What happened
The researchers modeled moons roughly 500 to 1,000 km in radius being struck by smaller space rocks with enough energy to shatter them. The simulations tracked millions of fragments as they heated, broke apart, and later re‑accreted into a new body. After the reassembly, the team followed the thermal evolution of the rebuilt moons for billions of years to see if liquid water could persist.
What the reports add
Lead author Marc Neveu, an astronomy associate research scientist, explained that the simulations showed "those big collisions don’t really matter as far as oceans are concerned. If there was an ocean before, there’s likely to be an ocean after and vice versa." The study also highlighted that while the presence of an ocean may survive, the heat from an impact could leave surface signatures, such as softened craters on Saturn’s moon Rhea.
What was said
Neveu told Scitechdaily, "It’s like building a snowman in the winter, and then a week later, there’s been warming and sunlight so the snowman is melting away… The heat came from below. A long‑ago collision that boosted an interior ocean could help explain why the moon appears that way."
How it came about
The work combined impact‑physics models with a separate interior‑evolution code developed with collaborators at the Southwest Research Institute and the Weizmann Institute of Science. By linking the two, the team could assess both the immediate aftermath of a moon‑shattering event and the long‑term thermal state that governs ocean stability.
Key facts
- Simulations show icy moons can retain subsurface oceans after catastrophic collisions. (scitechdaily.com)
- The study modeled moons 500–1,000 km in radius struck by smaller space rocks. (scitechdaily.com)
- Heat from impacts may leave surface features such as softened craters, as seen on Saturn’s moon Rhea. (scitechdaily.com)
Sources
- [1] scitechdaily.com — originally reported as “Scientists Simulated Moons Being Blown Apart – and Found Something Unexpected”
