Europa may have deep-sea volcanoes
Jupiter moon may be an even more promising abode for life than scientists thought
Anew study suggests volcanoes may lurk on the seabed of Europa, which harbours a vast ocean of salty water beneath its icy shell. Active volcanoes could power deep-sea hydrothermal systems, environments rich in chemical energy that potential Europa life forms could exploit.
“Our findings provide additional evidence that Europa’s subsurface ocean may be an environment suitable for the emergence of life,” said Marie Běhounková of Charles University in the Czech Republic. “Europa is one of the rare planetary bodies that might have maintained volcanic activity over billions of years, and possibly the only one beyond Earth that has large water reservoirs and a long-lived source of energy,” she added.
Běhounková and her colleagues modelled in detail how Europa’s interior stretches and flexes as the moon is tugged by Jupiter’s powerful gravity. Such deformation generates frictional heat, which keeps Europa’s buried ocean from freezing over – and perhaps even partially melts the upper layer of the moon’s rocky mantle.
Such melting may have fuelled seabed volcanoes for most of Europa’s history, perhaps even to the present day. Volcanic activity is most likely near Europa’s poles, where the internal heat loads are most intense.
Volcanoes on a Jovian satellite would not be unprecedented. One of Europa’s fellow Galilean moons, Io, is the most volcanically active body in the Solar System, and its eruptions are fuelled by the same type of gravitational tugging that Europa experiences. In a decade or so, researchers should be able to test and supplement such Europa modelling work with a wealth of new data thanks to NASA’s planned Europa Clipper mission.
Clipper is scheduled to launch in 2024 and arrive in orbit around Jupiter in 2030. The probe will then make about 50 close flybys of Europa over four Earth years, characterising the moon’s subsurface ocean, studying its icy shell and scouting out good touchdown sites for a future life-hunting lander, among other tasks.