In a major breakthrough study, scientists at Brown University in the US have found evidence of tectonic plates pushing against one another, a process known as subduction – producing the energy needed for life.
Brandon Johnson, an assistant professor in the Department of Earth, Environmental and Planetary Sciences at Brown University said: “If indeed, there’s life in that ocean, subduction offers a way to supply the nutrients it would need.”
Such nutrients include oxidants, electron-stripping substances that are common on Europa’s surface and that could help provide an energy source for life, according to the researchers.
On Earth subduction is driven primarily by temperature differences between relatively cool, dense rocky plates and the super hot surrounding mantle.
Europa’s icy surface means that heat cannot be the driving force, but the researchers claim that it does not mean subduction cannot happen.
According to Mr Johnson’s team computer models suggest that Europa’s ice plates can indeed dive — if they are saltier than their surroundings.
The assistant professor said: “Adding salt to an ice slab would be like adding little weights to it because salt is denser than ice.”
“So, rather than temperature, we show that differences in the salt content of the ice could enable subduction to happen on Europa.”
“It’s fascinating to think that we might have plate tectonics somewhere other than Earth.
”Thinking from the standpoint of comparative planetology, if we can now study plate tectonics in this very different place, it might be able to help us understand how plate tectonics got started on the Earth.”
The news comes as scientists working at NASA’s Goddard Space Flight Center in Maryland may have found compelling evidence Pluto could support life.
New research suggests that distant worlds such as Pluto and others such as Eris could have watery oceans sloshing beneath their icy exterior.
Lead author Prabal Saxena, of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, said: “These objects need to be considered as potential reservoirs of water and life.
“If our study is correct, we now may have more places in our solar system that possess some of the critical elements for extraterrestrial life.”