Scientists say there may be hot springs bubbling beneath the icy surface of a tiny Saturn moon.
If confirmed, it would make the moon Enceladus the only other known body in the solar system besides Earth where hot water and rocks interact underground.
"This is the first time ever outside of the Earth that we've discovered this kind of warm activity going on in another place," remarked Jet Propulsion Laboratory scientist Linda Spilker.
Such activity would also make the moon an even more attractive place in the hunt for microbial life.
Scientists say for life as we know it to form, there must be liquid water, organic compounds and energy.
Saturn’s moon Enceledus is known to have a liquid water ocean under an icy shell and a rocky core providing the organic compounds.
Now, this new research from Cassini suggests the moon has energy as well in the form of hot vents on the ocean floor.
Combine all of these ingredients and exciting things could happen, said Spilker.
"A lot of chemistry is happening and you are actually staring to create many of the chemicals associated with life."
The evidence for the hot vents comes from material collected when Cassini flew through plumes of mist ejected by the icy moon.
The spacecraft previously uncovered an underground ocean and a giant plume of gas and ice streaming from these cracks in the south polar region.
The samples were analyzed by two independent teams of scientists, one studying methane found in the plumes and one studying small rock particles.
They both reached the same conclusion: the material were likely formed by hydrothermal activity.
This occurs when water seeps into rocky material and creates chemical reactions that release heat and compounds like methane and hydrogen.
These vents are cooking about six miles below Enceldus' thick mantle of ice and are believed to reach temperatures of almost 200 degrees fahrenheit.
Spilker says the would be akin to similar vents on Earth known as "white smokers." These form deep on the ocean floor and life thrives around them.
NASA thinks maybe the same is happening on this icy moon millions of miles away.