Cassini detected some of the chemical elements needed for life in plumes of gas and particles erupting from the moon's surface.
However, the moon of Saturn has "almost all of the ingredients that you need to support life as we know it on Earth", said NASA scientist Linda Spilker.
The vapor or gas contains hydrogen, one of the essential components of life. One form of chemical energy has been noted as being able to feed life, which appears to exist on Saturn's moon called Enceladus.
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On Thursday, NASA scientists said they have detected evidence that this kind of chemical reaction is likely occurring under the surface of Enceladus.
"This is the closest we've come, so far, to identifying a place with some of the ingredients needed for a habitable environment", shared Thomas Zurbuchen, the associate administrator for NASA's Science Mission Directorate at Headquarters in Washington.
NASA's Planetary Science Division Director, James Green, said: "We're pushing the frontiers". Researchers speculate that, as with Enceladus, this could be evidence of water erupting from the moon's interior.
The hydrogen, which shoots out of the moon in high-powered ice jets, is the final puzzle piece following the discovery of its liquid ocean and carbon dioxide.
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But former President Hamid Karzai accused the United States of using Afghanistan as "a testing ground for new and risky weapons". The exact death toll is unclear, with one Afghan official quoting the number as 92, and another claiming 90 people were killed.
Meanwhile, Dr. David Clements, astrophysicist at Imperial College London, said: 'This discovery does not mean that life exists on Enceladus, but it is a step on the way to that result'.
The Cassini spacecraft found hydrogen in the plume of gas and icy material spraying from Enceladus during its last, and deepest, dive through the plume on October 28, 2015. The plumes include 1 percent hydrogen and the remainder is a combination of molecules such as ammonia, carbon di oxide, and methane.
Cassini has found that nearly all of these ingredients are there on Enceladus, a tiny icy moon at a distance of a billion miles away from Saturn.
For life to persist on any planet, it needs three vital energy sources: liquid water, right chemical ingredients (hydrogen, oxygen, nitrogen, sulfur, carbon, and phosphorus), and an energy source for metabolism.
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However, given the paucity of goals from both these teams in recent weeks and given team news, Under 2.5 is a decent shout. He said: "If we are talking about the goalkeeper for that goal, it's very hard for a goalkeeper".
Europa is potentially billions of years older than Enceladus, and life takes time to emerge. The Europa Clipper mission is set to launch to Europa in the 2020s.