The Europa Clipper is scheduled for launch in 2024 in full defiance of advice from astronaut David Bowman. Once of the many things the Clipper will be to search for signs of plume activity on Jupiter’s most famous moon. Here’s more via Centauri Dreams:
So plumes are in play for Europa Clipper, and the new research finds evidence of a process that can produce them. The paper in Geophysical Research Letters focuses on what the authors call brine migration, in which small pockets of salty water migrate within the ice to warmer icy areas. We get into questions of salinity in this work because migration of icy brines, analyzed here through study of the impact crater Manannán, may have resulted in the creation of a plume. Imaging data from the Galileo mission allowed the team to study the resulting surface feature and to calculate that Europa’s ocean is about a fifth as salty as Earth’s.
If eruptions from the ocean below periodically break through the ice, we might have a way to sample ocean materials without ever trying to drill through the surface shell. The new work, led by Gregor Steinbrügge (Stanford University) homes in on Manannán, a 30-kilometer wide crater on Europa that is the result of an impact some tens of millions of years ago. The paper models the melting and refreezing of water following the event. And it suggests that not all plumes carry materials from the ocean below.