Identifying Signatures Of Past And Present Cryovolcanism On Europa

Europa, the most visibly active icy moon of Jupiter, is a prime target for the search for life in the outer solar system.

Two spacecraft missions, Europa Clipper from the National Aeronautics and Space Administration (NASA) and the Jupiter Icy Moon Explorer (JUICE) from the European Space Agency (ESA), will observe its surface, probe its interior structure, and characterize the space environment starting in 2030. Occasional eruptions of water sourced from Europa’s interior may provide a window on the interior conditions and habitability of the moon.

Here, we investigate the storage and evolution of briny water in Europa’s ice shell and propose a framework to interpret spectral, thermal, radar and gravity data collected by future missions.

We show that it is possible to discriminate between water erupting from the deep ocean or from shallow liquid reservoirs using combined measurements of the material’s salinity, surface temperature and ice shell thickness.

Observable signatures and freezing characteristics for the 1 km thick reservoir located 1 km deep below Europa’s surface. a Cumulative erupted volume, b surface temperature anomaly, c local ice shell thickness, d cryomagma freezing temperature, e freezing rate, and (f) volumic frozen fraction. Time (x-axis) scales differ between panels. The emplacement mechanism of the source reservoir is beyond the scope of this study. — Nature

• Identifying signatures of past and present cryovolcanism on Europa, Nature (open access)
• Identifying signatures of past and present cryovolcanism on Europa, Nature via NASA NTRS (open access)

Astrobiology