- September 11, 2026
- By Georgia Jiang
Catastrophic collisions between icy moons barely disturb the hidden oceans beneath their frozen surfaces, offering new insights into life beyond Earth, according to a University of Maryland-led study published last month in the journal Nature Astronomy.
Many of the moons orbiting Saturn, Uranus and Neptune likely conceal oceans of liquid water beneath miles of icy shell. Because life as we know it needs water, these buried oceans rank among the most promising places to search for life beyond Earth.
But the outer solar system is akin to a celestial demolition derby. Scientists suspect some of today’s moons are reassembled remnants of earlier generations of moons, shattering and reforming from space debris. Do these collisions also destroy a moon’s ocean and with it, any chance for life?
“What we found was that those big collisions don't really matter as far as oceans are concerned,” explained the study’s lead author, Marc Neveu, an astronomy associate research scientist at UMD. “If there was an ocean before, there's likely to be an ocean after and vice versa.”
For the NASA-funded research, he and his co-authors at the Southwest Research Institute in Colorado and the Weizmann Institute of Science in Israel simulated the violent physics of a cosmic crash, comparing it to another simulation of the slow burn of a moon’s interior over billions of years.
Combining these two methods allowed the researchers to follow two sizes of moons, roughly 500 and 1,000 kilometers in radius, as the moons were struck by smaller space rocks, blown apart and reassembled. For both types of moon, oceans survived the impacts, getting thicker on larger moons and thinner on smaller moons—but in neither case did a collision create an ocean where only solid ice was before.