"We're moving towards Enceladus's ocean being habitable, but we're not making any claims at this point about it being inhabited", lead author Hunter Waite, with the Southwest Research Institute in San Antonio, Texas, said in an interview.
Cassini has detected hydrogen molecules in vapour plumes emanating from cracks in the surface of Enceladus, a small ocean moon coated in a thick layer of ice, the USA space agency said.
"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". The other two necessary ingredients are liquid water and the right chemical ingredients, primarily; carbon, hydrogen, oxygen, nitrogen, phosphorus and sulphur. The other two, phospor and sulfur, have yet to be discovered, but scientists are confident that the elements are there, since Enceladus is believed to have a core similar to that of meteorites that have those two in abundance.
The Juno spacecraft is in orbit around Jupiter, but the mission has been designed in such a way that Juno does not go anywhere near Europa, to avoid contaminating the icy moon in case it had life. A possible plume of material has also been spotted erupting from the surface of Europa past year, in the same place that one was spotted by Hubble in 2014.
WASHINGTON-NASA has announced that there may be proof of life outside of earth. From these observations scientists have determined that almost 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.
Cassini's INMS was devised to sample the upper atmosphere of Saturn's moon Titan. At a press conference last week, scientists at the Jet Propulsion Laboratory (JPL) reviewed some of Cassini's key findings to date, including the plumes from Enceladus, a small moon that has a liquid ocean under an icy crust.
"Most of us would be excited with any life", said Mary Voytek, an astrobiology senior scientist for NASA. But deep in the ocean, some microbes derive energy from a totally difference source: a chemical process between warm water and rock that produces molecular hydrogen. That's what the plumes are about on Europa as well. The plume's reach was apparently 62 miles (100 kilometers) above Europa's surface. Researchers speculate that, as with Enceladus, this could be evidence of water erupting from the moon's interior. "Between there and what may exist on Europa and in subsurface water on Mars, the more we keep looking, the more tantalizing it becomes - that there may be life and there may be life in multiple locations". "We want to protect those moons from any bacteria that may be carried on the spacecraft from the Earth, so it's still a pristine environment".
In the final stages of its 13-year-long exploration, Cassini continued its voyage to discover that there is a salty, global ocean under Enceladus' icy crust. In 2014, data from the earth-orbiting Hubble Space Telescope suggested that it also may have plumes. Both plumes, photographed in UV light by Hubble, were seen in silhouette as the moon passed in front of Jupiter.
The possibility of an ocean under Europa's crust, never mind plumes, was unknown when Galileo was built, so it was not created to look for them. Close-up measurements will have to wait until the 2020s when NASA plans to launch missions whose entire objective is investigating Europa.
Astronomers are reluctant to say anything conclusive about the observations of Europa's plume, but Sparks said it "at least makes it an interesting place to look" for more surprises. The much larger Europa, if it has life too, is a better prospect.