Surface of Jupiter’s Moon Europa Churned by Small Impacts

Jupiter’s moon Europa and its global ocean may currently have conditions suitable for life. Scientists are studying processes on the icy surface as they prepare to explore.

 

Jupiter’s icy moon Europa and its global ocean may currently have conditions suitable for life. Scientists are studying processes on the icy surface as they prepare to explore. It’s easy to see the impact of space debris on our Moon, where the ancient, battered surface is covered with craters and scars. Jupiter’s icy moon Europa withstands a similar trouncing – along with a punch of super-intense radiation. As the uppermost surface of the icy moon churns, material brought to the surface is zapped by high-energy electron radiation accelerated by Jupiter.

 

NASA-funded scientists are studying the cumulative effects of small impacts on Europa’s surface as they prepare to explore the distant moon with the Europa Clipper mission and study the possibilities for a future lander mission. Europa is of particular scientific interest because its salty ocean, which lies beneath a thick layer of ice, may currently have conditions suitable for existing life. That water may even make its way into the icy crust and onto the moon’s surface.

 

The new study, which was published July 12, 2021 in the journal Nature Astronomy, is a bit more pessimistic. In it, researchers modeled how Europa’s surface is disturbed by small but frequent impacts — a real issue for a world without a substantial atmosphere to burn up incoming hunks of rock and ice.
 

They found that such “impact gardening” likely churns the top 12 inches (30 cm) or so of Europan ice significantly, bringing previously buried bits up to the surface, where radiation can zap any interesting molecules into unrecognizable goo. “If we hope to find pristine, chemical biosignatures, we will have to look below the zone where impacts have been gardening,” study lead author Emily Costello, a planetary research scientist at the University of Hawaii at Manoa, said in a statement. “Chemical biosignatures in areas shallower than that zone may have been exposed to destructive radiation.”

 

Previous work has suggested that just 8 inches (20 centimeters) of ice could likely shield any biomolecules that might exist on Europa from that punishing radiation environment, even in the hardest-hit regions of the moon. 

Read the full article at: www.jpl.nasa.gov