Seafloor volcanoes may be supporting life on icy Europa
Jupiter’s Icy moon Europa may have enough internal heat to trigger volcanic activity on the floor of its global ocean, according to the results of a new study. Despite being encased in a shell of water ice, Europa is considered to be one of the most promising locations in our solar system for extraterrestrial life.
Scientifically speaking, Europa is one of the most fascinating and enigmatic bodies in our solar system. The outer surface of its miles-thick ice shell is riven with bands and ridges, along with other pieces of unusual geology that likely results from the extreme gravitational influence of nearby Jupiter.
However, it is what lies underneath the surface that has captured the attention of the scientific community. There is a wealth of evidence to suggest that Europa hosts a global ocean beneath the surface ice, and many members of the scientific community believe that this hidden body of water may be capable of hosting primitive forms of extraterrestrial life.
The new study now further supports the idea that Europa may be hospitable to the emergence of life, by revealing that volcanic activity could still be occurring deep down on the ocean floor.
An international team of scientists used three-dimensional numerical modelling and advanced computer simulations of the icy moon to discover how the strong gravitational interaction between Jupiter and its moon generates heat deep within Europa, and how it is then transferred through the rocky inner section of the world.
As tiny Europa completes an orbit around Jupiter, the gas giant’s gravitational influence causes the entire moon to flex. The friction brought about by this immense gravitational force causes large amounts of heat energy to build up in the moon’s rocky interior, below the global subsurface ocean.
According to the new research, the heat generated by the tidal friction may be intense enough to melt through the crust, and give rise to volcanoes on the seafloor. These geological features would most likely emerge near Europa’s polar regions, where the structural stress from Jupiter's gravity is at its greatest.
As is the case on Earth, the interaction between volcanoes – or smaller-scale hydrothermal features – and salty water would provide a relatively hospitable chemical environment for the evolution of extremophile life forms.
Future missions such as NASA’s Europa Clipper – which is due to arrive in the Jovian system in 2030 – will be well-equipped to probe Europa for signs of deep sea volcanic activity using instruments designed to examine the moon’s composition and gravitational properties.
"Our findings provide additional evidence that Europa’s subsurface ocean may be an environment suitable for the emergence of life," explains the study's lead author Marie Běhounková, from the 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."
A paper on the study has been published in the journal Geophysical Research Letters.