The U.S. space agency NASA has identified a moon orbiting Saturn as a new candidate for potential life.
NASA's Cassini spacecraft said the icy, ocean-covered body possesses ample amounts of hydrogen gas. The gas could be a chemical energy source of life, scientists involved with the mission said.
Thomas Zurbuchen, associate administrator for NASA's Science Mission Directorate in Washington, called Saturn's moon Enceladus "the closest we've come" to identifying a planet with the necessary ingredients for a habitable planet.
"These results demonstrate the interconnected nature of NASA's science missions that are getting us closer to answering whether we are indeed alone or not," he said in a statement.
The paper from researchers with the Cassini mission was published Thursday in the journal Science.
The Cassini spacecraft detected the hydrogen in a plume of gas and icy material spraying off Enceladus in October 2015. Scientists determined the gas in the plume nearly 98 percent water, about 1 percent of which is hydrogen, with the rest being a mixture of carbon dioxide, methane and ammonia.
The scientists noted that "life as we know it requires three primary ingredients": liquid water, a source of energy for metabolism, and a combination of chemical ingredients that include hydrogen, nitrogen and oxygen, among others.
"With this finding, Cassini has shown that Enceladus — a small, icy moon a billion miles farther from the sun than Earth — has nearly all of these ingredients for habitability," NASA said in a statement announcing the findings.
While some ingredients for life were found on Enceladus, the scientists made clear that the discovery didn't confirm life on the planet, but merely confirmed favorable conditions.
"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.