“If we’ve learned anything about life on Earth, it’s that where there’s liquid water, there’s generally life,”

“And of course our ocean is a nice, salty ocean. Perhaps Europa’s salty ocean is also a wonderful place for life.”

Scientists are pretty confident Europa is home to a vast subterranean ocean, but could it have any water on its surface? According to a new study, maybe yes. That’s big news for anyone hoping to send a robotic explorer to the icy moon. And it could be big news for anyone interested in the possibility of life on that Jovian satellite.

Salty water from Europa’s 60-mile-thick ocean makes its way to the surface somehow through cracks in its ice sheet, according to new research. Once it’s there, it is exposed to sulfur from the neighboring moon Io, Jupiter’s largest. Magnesium chloride in the water interacts with the sulfur and produces magnesium sulfate, according to an analysis by astronomers Mike Brown of Caltech and Kevin Hand of the Jet Propulsion Laboratory.

This is interesting because it shows that Europa has some kind of chemical activity and energy transfer at its surface, the astronomers note in a new paper. That’s important for life-hunters because any alien creatures living on the frigid moon would need an energy source–the sun is far too dim at that distance to really do anything.