"This finding does not mean that life exists there, but it makes life more plausible and potentially quite abundant if a fraction of the hydrogen is used to drive biology", Jeffrey Kargel, a professor at the University of Arizona, told The Guardian.
Hydrogen was detected by Cassini's instruments in a massive plume of water that spouted from Enceladus' surface in 2015.
Two moons - one of Saturn, the other of Jupiter - show evidence of the ingredients needed to support life, NASA said on Thursday.
Enceladus is Saturn's sixth largest moon, was discovered in 1789 and is 1.272 billion kilometers (0.790 billion miles) away from Earth.
"With this finding, Cassini has shown that Enceladus - a small, icy moon a billion miles farther from the sun than Earth - has almost all of these ingredients for habitability", NASA said in a statement announcing the findings.
The hydrogen and the methanogenesis could well provide a food source for microbes, experts think, in the same way it does on Earth.More news: In South Africa, 18 students killed in bus crash
On Thursday, April 14, NASA shared that "chemical energy", existed on Enceladus, which may support life on Staurn's icy moon. Both of these moons are fairly similar and are judged as the two of the most likely places in our solar system to find alien life.
Meanwhile, Cassini's longstanding mission is soon coming to an end.
The plumes are 98 percent water, scientists said, with traces of molecules including ammonia, carbon dioxide and methane.
From information obtained by the spacecraft, there is evidence of chemical reactions under the icy surface of the moon.
In a related perspective, Jeffrey Seewald of the Woods Hole Oceanographic Institution, who was not involved in the study, described the findings as "an important advance in assessing the habitability of Enceladus".
William Sparks, an astronomer with the Space Telescope Science Institute in Baltimore, said the results are "intriguing as they found a repeating plume candidate at a position of a Thermal anomaly". "It would be like a candy store for microbes", said Hunter Waite, lead author of the study appearing today in the journal Science. These were observed at the same location where Hubble saw evidence of a plume in 2014.
"We're pushing the frontiers - we're finding new environments", said Jim Green, director of the Planetary Science Division at NASA Headquarters.