NASA detects hydrogen gas on Saturn’s moon Enceladus

NASA detects hydrogen gas on Saturn’s moon Enceladus

NASA scientists have announced that the agency’s Cassini spacecraft has detected hydrogen gas in a plume gushing from a liquid water ocean hidden beneath the icy shell of Saturn’s moon Enceladus.

Hydrogen is a key energy source for microbial life and its detection in Enceladus’ atmosphere has boosted scientists’ belief that some of Saturn’s moons could be supporting alien life in the form of microbes.

Linda Spilker, project scientist on the Cassini mission, said, “This is a very significant finding because the hydrogen could be a potential source of chemical energy for any microbes that might in be in Enceladus’s ocean.”

Meanwhile, NASA’s Hubble Space Telescope has detected a 62-mile-high water plume near Europa’s equator. The new plume candidate is in the same location in which a smaller water plume was detected by the same telescope back in March 2014.

The new discoveries are encouraging scientists to continue to explore the Saturn system. NASA has plans to launch a $2-billion Europa Clipper mission sometime in the early to mid-2020s.

NASA official release informed....

The Cassini spacecraft detected the hydrogen in the plume of gas and icy material spraying from Enceladus during its last, and deepest, dive through the plume on Oct. 28, 2015. Cassini also sampled the plume's composition during flybys earlier in the mission. From these observations scientists have determined that nearly 98 percent of the gas in the plume is water, about 1 percent is hydrogen and the rest is a mixture of other molecules including carbon dioxide, methane and ammonia.

The measurement was made using Cassini's Ion and Neutral Mass Spectrometer (INMS) instrument, which sniffs gases to determine their composition. INMS was designed to sample the upper atmosphere of Saturn's moon Titan. After Cassini's surprising discovery of a towering plume of icy spray in 2005, emanating from hot cracks near the south pole, scientists turned its detectors toward the small moon.

Cassini wasn't designed to detect signs of life in the Enceladus plume – indeed, scientists didn't know the plume existed until after the spacecraft arrived at Saturn.

"Although we can't detect life, we've found that there's a food source there for it. It would be like a candy store for microbes," said Hunter Waite, lead author of the Cassini study.

The new findings are an independent line of evidence that hydrothermal activity is taking place in the Enceladus ocean. Previous results, published in March 2015, suggested hot water is interacting with rock beneath the sea; the new findings support that conclusion and add that the rock appears to be reacting chemically to produce the hydrogen.

The paper detailing new Hubble Space Telescope findings, published in The Astrophysical Journal Letters, reports on observations of Europa from 2016 in which a probable plume of material was seen erupting from the moon’s surface at the same location where Hubble saw evidence of a plume in 2014.