Hydrothermal vent

Food for microbes found on Enceladus

Enceladus’ plume
FINDING FOOD A deep dive into Enceladus’ plume, shown here in an artist’s illustration, reveals that the moon harbors molecular hydrogen. On Earth, the gas serves as a food source for some microbes, suggesting life could exist on Enceladus, too.

Saturn’s icy moon Enceladus packs snacks suitable for microbial life.

Data from the Cassini spacecraft show that the vaporous plume shooting out of the moon’s southern pole contains molecular hydrogen. It is probably generated when water in the moon’s subterranean ocean reacts with rock in its core, researchers report in the April 14 Science. Such reactions at hydrothermal vents and in other extreme environments on Earth produce high abundances of hydrogen, which some microbes use for food. There’s enough hydrogen on Enceladus to sustain microbial life, the team suggests.

“We are not saying Enceladus has life, but the discovery does move the moon higher on the list of potentially habitable places in the solar system,” says study coauthor J. Hunter Waite of the Southwest Research Institute in San Antonio.

Enceladus became a good target for finding life beyond Earth when researchers found a global ocean under the moon’s icy exterior and hints of hydrothermal activity (SN: 10/17/15, p. 8; SN: 4/18/15, p. 10)….