Discovering Europa's Ice Shell
Europa, one of Jupiter's moons, is enveloped by a water-ice crust. Despite a surface temperature of -160°C, beneath this icy exterior, a subsurface ocean might harbor twice as much water as Earth's oceans.
Probing the Ice Depth
Europa's ice shell thickness ranges from 15 to 25 kilometers. Recent data suggest regions of thin ice might exist, potentially allowing ocean water to seep up and freeze in unique patterns detectable by spacecraft.
Chaotic Terrain Mystery
Europa's surface displays 'chaotic terrain', areas of disrupted ice turned on its side. This suggests a dynamic environment where the ice surface interacts with the subsurface ocean, possibly due to tidal heating.
Hidden Lakes Within Ice
Scientists theorize that Europa may have shallow subsurface lakes embedded within its ice shell. These lakes could influence surface features and might be habitats for life, analogous to Antarctic subglacial lakes on Earth.
Salt from the Ocean
Spectrographic analysis shows that Europa's surface ice contains salts, likely from the ocean below. These salts could provide essential chemistry for life, indicating that the subsurface ocean is interacting with the rocky mantle.
Tidal Flexing Effects
Jupiter's gravitational pull creates significant tidal forces on Europa, causing flexing and heating. This tidal heating could maintain the liquid state of the ocean beneath the ice, making it one of the best places to search for extraterrestrial life.
Future Europa Missions
Upcoming missions, like NASA's Europa Clipper and ESA's Jupiter Icy Moons Explorer (JUICE), aim to study Europa's ice shell and ocean in detail. They may even sample the icy plumes ejected from the surface.