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The Cassini’s spacecraft mission to Saturn and its study of the systems of rings and moons brought many surprises.

“At the time of its design, we had no idea that ocean worlds existed in the outer solar system.”

These ocean worlds could mean life.One unexpected discovery came from the south pole of Enceladus, a moon embedded in one of Saturn’s rings.

“It has a liquid water ocean underneath and it shoots geysers. So these cracks open up and geysers shoot up.”

Instruments on Cassini have been able to detect the gas coming from that geyser plume.

“We know that there are salts. Now this is important for life because life needs certain minerals and salts to exist.We have very strong evidence that there are hydro-thermal vents down at that base of that ocean, the ocean floor.Now any time you find hydro-thermal vents here on Earth, you find rich communities of organisms.”

Cassini was also able to gather data from Saturn’s largest moon,Titan, which has lakes and seas of liquid methane and ethane instead of water.There is also evidence of a liquid ocean beneath the surface that probably contains ammonia and water.Scientists and engineers say the environment could still hold life.

“We’re still open to trying to look for weird life in places like this and we found a strange place right here in our own solar system.”

How to dispose of Cassini now that is running out of fuel is something scientists and engineers are trying to figure out since they do not want any earthly organisms that may be on Cassini to contaminate a moon that may have life.

“I want to find life elsewhere in a place like Enceladus but I don’t want to realize later on that we put it there.”

Scientists and engineers are already envisioning future missions back to Saturn and its moons to look deeper into the possibility of life.

“And I think with today’s instrumentation, things that we could put on a spacecraft right now,we could find that life with our instruments of today.”

It looks like the end of Cassini will be a death dive into Saturn’s atmosphere, sending critical data to Earth until the very end.It’s information that will be studied and analyzed by scientists long after the end of Cassini.

Elizabeth Lee, VOA news, Los Angeles.