Greenland Provides Insight into the Possibility of Liquid Water in Europa’s Icy Shell

Posted byAaron Gronstal

Researchers supported by NASA have identified and analyzed surface features known as double ridges in Northwest Greenland in order to better understand similar features on Jupiter’s moon Europa. Double ridges are common on the surface of the icy moon, but their formation is poorly understood. The team of researchers spotted similar features in Greenland, but at a much smaller scale. The ridges on Europa have much larger and taller peaks, which might be attributed to Europa’s lower gravity.

A double ridge cutting across the surface of Europa is seen in this mosaic of two images taken by NASA’s Galileo during the spacecraft’s close flyby on Feb. 20, 1997.Image credit: NASA/JPL/ASU.

Through their work in Greenland, scientists have revealed that double ridge features form when liquid water trapped in the ice sheet undergoes refreezing, pressurization and fracturing. When water from a nearby lake drained into the ice sheet, the resulting pocket of water then froze and caused the overlying ice to fracture and form peaks on either side. The study indicates that shallow liquid water could be present within the ice shell of Europa, and the team believes that this water could making its way into the ice from the ocean below.

The study, “Double ridge formation over shallow water sills on Jupiter’s moon Europa” was published in the journal Nature Communications. The researchers are part of the Network for Ocean Worlds, a NASA Research Coordination Network.

Click here to read a recent post from Many Worlds discussing this research.

Schmidt, BE, et. al. (2011) “Active formation of ‘chaos terrain’ over shallow subsurface water on Europa,” Nature, 479, 502–505.

The Many Worlds Blog chronicles the search for evidence of life beyond Earth written by author/journalist Marc Kaufman. The “Many Worlds” column is supported by the Lunar Planetary Institute/USRA and informed by NASA’s NExSS initiative, a research coordination network supported by the NASA Astrobiology Program. Any opinions expressed are the author’s alone.