Hydrogen is an excellent source of chemical energy that supports life near deep sea hydrothermal vents on Earth.
While the Enceladus finding is intriguing on its own, NASA also released a paper today detailing the fact that the Hubble Space Telescope has again found plumes jetting off of Jupiter's moon Europa in the same location one was spotted on in 2014.
The necessary ingredients for life as we know it include liquid water, energy sources and chemicals such as carbon, hydrogen, oxygen, nitrogen, sulfur and phosphorus.
The findings from the Cassini mission reveal that almost all of these ingredients have been detected on Enceladus, except for phosphorous and sulfur. This is because the rocky core of the icy Saturn moon is believed to have similar chemical properties to meteorites, which contain both sulfur and phosphorus.
NASA scientists have detected hydrogen from hydrothermal vents in ice plumes from Saturn's ocean-bearing moon Enceladus in conditions which they say could have led to the rise of life on Earth.
The plumes are 98 percent water, scientists said, with traces of molecules including ammonia, carbon dioxide and methane.
Lead scientist Dr Hunter Waite said the result showed the moon's environment would be "like a candy store for microbes" with a constant and plentiful food source.
"This is the closest we've come, so far, to identifying a place with some of the ingredients needed for a habitable environment", said NASA administrator Thomas Zurbuchen. Most notably, this ocean world, as the space agency calls it, has ample amounts of hydrogen gas in its oceans, something that may work with carbon dioxide in the oceans' waters to support life.
Cassini also sampled the plume's composition during flybys earlier in the mission.
"Ingredients for life" exist on Saturn's moon Enceladus and Jupiter's moon Europa, according to an announcement by NASA on Thursday. Those traces are all signs of the presence of life as we know it.
An illustration of NASA's Cassini spacecraft flying through the water plumes of Enceladus, an icy moon that orbits Saturn.
It appears hydrogen gas is pouring into Enceladus' ocean from geothermal activity closer to the center of the moon. A possible plume of material has also been spotted erupting from the surface of Europa previous year, in the same place that one was spotted by Hubble in 2014.
Europa is potentially billions of years older than Enceladus, and life takes time to emerge.
NASA is planning for a new mission known as the Europa Clipper mission, which is now slated for the early 2020s.