Evidence for Liquid Water on Saturn's Moon

Flybys find signs of hidden H₂O

By Laurie J. Schmidt Posted 12.05.2008 at 1:04 pm 7 Comments

Enceladus Ice Geysers Cassini Imaging Team, NASA

Beneath the central Antarctic ice sheet lies Lake Vostok -- a frozen freshwater lake about the size of Lake Ontario, with depths up to 650 feet. Now, scientists believe that Saturn's icy moon Enceladus may harbor a similar underground reservoir.

In 2005, high-resolution images from the Cassini-Huygens mission to Saturn and Titan revealed icy jets and plumes ejecting particles into space above the southern polar region of Enceladus. After examining several models, researchers working on the Cassini mission theorized that the source of the plumes could be pockets of liquid water close to the surface of Enceladus -- like icy versions of Yellowstone's Old Faithful geyser.

In 2008, Cassini completed several "flybys" of Enceladus, including one on October 9 that brought the spacecraft to within just 16 miles of the moon's surface -- the closest flyby yet of any Saturn moon. Thanks to Cassini's cameras and instruments, these flybys gave researchers a closer look at the plumes. Scientists from NASA's Jet Propulsion Laboratory, the University of Colorado, and the University of Central Florida teamed up to analyze both the water vapor plumes and the ice particles being ejected from the moon. Their conclusion? That the plumes may come from a liquid water source beneath the surface of Enceladus. According to the scientists, the geysers' behavior supports a mathematical model that treats the vents as nozzles that channel water vapor from a liquid reservoir to the moon's surface at supersonic speeds. The team's findings were reported in the November 27 issue of the journal Nature.

Because water is a fundamental requirement of life, the presence of liquid water on Enceladus would have major implications for the possibility of life within icy bodies of the outer solar system. Currently, liquid water is only known to exist in two places in the solar system: Earth and Jupiter's moon Europa.

Further studies of Enceladus are a prime goal of Cassini's "Equinox Mission," which is now underway and will continue through September 2010.

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7 Comments

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JonahBioHonors

12/07/08 at 11:36 pm

This article is very interesting in that if we find enough water on Enceladus, we may discover new life outside of Earth! And if life is on Enceladus then we may be looking at a future home as oil and coal is slowly but surely reaching depletion.

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bdhoro87

from coral gables, fl

12/08/08 at 10:07 am

I have doubts that people would recognize extra terrestrial life near Saturn if it was probing us. There's not even an accepted definition of life and we're looking for complicated forms of it that we probably won't recognize.

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OOTWOguy

12/08/08 at 2:43 pm

This is very interesting in deed, but we have through this about Europa for years. Now we may need to split the difference and look at both? I would like to see a comparison study to see which one would be the most likely to actually harbor or sustain a lifeform. Personally I am a Europa fan. We have not even been able to tap into Lake Vostok here on Earth so how in the world could we do it on Encladeus? We have however been able to sucessfully use a cryobot and have the technology to "drill" down into Europa. Who knows, we probably wont get to research wither of them, so for the time being we will dream. I like the dreams better anyway, like at www.ootwo.com/europa.asp . It is more fun to dream, but I would like to see that dream come true!
Aaron COO-OOTWO
www.ootwo.com

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Mike_R

12/08/08 at 9:28 pm

I don't think Enceladus will be a home for humans any time soon. If we do discover some kind of simple life in subterranean water reservoirs there, we'd probably want to quarantine it to avoid any cross contamination. It would be an astounding discovery, but as noted above, Europa is closer and probably has a much more extensive aquatic environment for any potential life. So keep your eyes on Europa -- it's much more likely to be the first place we see ET.

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Mike Cook

from Kent, WA

12/09/08 at 10:01 am

Well, if we don't find life in the water on Mars, we don't find it in the watery material in the asteroid belt, we don't find water on Europa, and we don't find it on Enceladus, then we will be forced someday to conclude that water alone doesn't guarantee there will be our kind of life.

But we should keep looking. By life I mean a prokaryotic cell that can reproduce itself. I would even accept a strange virus found in space as evidence, because the virus must have had a live host at some time.

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voig0048

12/13/08 at 10:57 am

There very possible could be life on Europa. But there is a difference between life and intelligent life. Life can consist of any type of organic substance like one cell organisms. As for intelligent life I propose this definition; any form of a living being that exhibits some form of communication and the ability to make and use tools. Of course with more understanding the definition could change.

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Claud

12/11/09 at 4:58 pm

this probably sounds really stupid, but my question is....why can't there be some sort of life which survives off of another substance besides water?