Ocean Discovery On Enceladus Spur Life-Hunting Missions to Icy Moons

Saturn's moon Enceladus, covered in snow and ice, resembles a perfectly packed snowball in this image from NASA's Cassini mission released on Dec. 23, 2013.

This view was taken by Cassini on March 10, 2012. It shows the leading side of Enceladus. 

North on Enceladus is up and rotated 6 degrees to the left.

Credit: NASA/JPL-Caltech/Space Science Institute

Astronomers are hoping that the existence of a subsurface ocean on Saturn's icy moon Enceladus will build momentum for life-hunting missions to the outer solar system.

Researchers announced their discovery of the deep watery ocean on Enceladus on Thursday (April 3) in the journal Science, confirming suspicions held by many scientists since 2005, when NASA's Cassini spacecraft spied geysers of ice and water vapor erupting from Enceladus' south pole.

The discovery vaults Enceladus into the top tier of life-hosting candidates along with Europa, an ice-sheathed moon of Jupiter that also hosts a subterranean ocean. Both frigid satellites bear much closer investigation, researchers say.



"I don't know which of the two is going to be more likely to have life. It might be both; it could be neither," study co-author Jonathan Lunine of Cornell University told reporters yesterday (April 2).

Jonathan Lunine

"I think what this discovery tells us is that we just need to be more aggressive in getting the next generation of spacecraft both to Europa and to the Saturn system once the Cassini mission is over."

Cassini arrived in orbit around Saturn in 2004 and is currently scheduled to go out in a blaze of glory in September 2017, when it will dive headlong into the giant planet's thick atmosphere.

Enceladus' geysers blast material hundreds of miles into space, offering a way to sample the moon's subsurface ocean from afar.

(Researchers think the ocean is feeding the geysers, though they can't be sure of this at the moment.)