[meteorite-list] NASA's Cassini Discovers Potential Liquid Water on Enceladus

[Ron Baalke]

March 9, 2006

Erica Hupp/Dwayne Brown 
Headquarters, Washington 
(202) 358-1237/1726 

Carolina Martinez 
Jet Propulsion Laboratory, Pasadena, Calif.
(818) 354-9382 

RELEASE: 06-088

NASA'S CASSINI DISCOVERS POTENTIAL LIQUID WATER ON ENCELADUS

NASA's Cassini spacecraft may have found evidence of liquid water 
reservoirs that erupt in Yellowstone-like geysers on Saturn's moon 
Enceladus. The rare occurrence of liquid water so near the surface 
raises many new questions about the mysterious moon. 

"We realize that this is a radical conclusion - that we may have 
evidence for liquid water within a body so small and so cold," said 
Carolyn Porco, Cassini imaging team leader at the Space Science 
Institute, Boulder, Colo. "However, if we are right, we have 
significantly broadened the diversity of solar system environments 
where we might possibly have conditions suitable for living 
organisms."

High-resolution Cassini images show icy jets and towering plumes 
ejecting large quantities of particles at high speed. Scientists 
examined several models to explain the process. They ruled out the 
idea the particles are produced or blown off the moon's surface by 
vapor created when warm water ice converts to a gas. Instead, 
scientists have found evidence for a much more exciting possibility. 
The jets might be erupting from near-surface pockets of liquid water 
above 0 degrees Celsius (32 degrees Fahrenheit), like cold versions 
of the Old Faithful geyser in Yellowstone. 

"We previously knew of at most three places where active volcanism 
exists: Jupiter's moon Io, Earth, and possibly Neptune's moon Triton. 
Cassini changed all that, making Enceladus the latest member of this 
very exclusive club, and one of the most exciting places in the solar 
system," said John Spencer, Cassini scientist, Southwest Research 
Institute, Boulder.

"Other moons in the solar system have liquid-water oceans covered by 
kilometers of icy crust," said Andrew Ingersoll, imaging team member 
and atmospheric scientist at the California Institute of Technology, 
Pasadena, Calif. "What's different here is that pockets of liquid 
water may be no more than tens of meters below the surface." 

"As Cassini approached Saturn, we discovered the Saturnian system is 
filled with oxygen atoms. At the time we had no idea where the oxygen 
was coming from," said Candy Hansen, Cassini scientist at NASA's Jet 
Propulsion Laboratory (JPL) in Pasadena. "Now we know Enceladus is 
spewing out water molecules, which break down into oxygen and 
hydrogen." 

Scientists still have many questions. Why is Enceladus so active? Are 
other sites on Enceladus active? Might this activity have been 
continuous enough over the moon's history for life to have had a 
chance to take hold in the moon's interior? 

In the spring of 2008, scientists will get another chance to look at 
Enceladus when Cassini flies within 350 kilometers (approximately 220 
miles), but much work remains after the spacecraft's four-year prime 
mission is over. 

"There's no question, along with the moon Titan, Enceladus should be a 
very high priority for us. Saturn has given us two exciting worlds to 
explore," said Jonathan Lunine, Cassini interdisciplinary scientist, 
University of Arizona, Tucson, Ariz.

Mission scientists report these and other Enceladus findings in this 
week's issue of Science. The Cassini-Huygens mission is a cooperative 
project of NASA, the European Space Agency and the Italian Space 
Agency.

JPL, a division of the California Institute of Technology, manages the 
Cassini-Huygens mission for NASA's Science Mission Directorate. The 
Cassini orbiter was designed, developed and assembled at JPL.

For Cassini images and information about the research on the Web, 
visit: 

http://www.nasa.gov/cassini 

http://saturn.jpl.nasa.gov 

For information about NASA and agency programs on the Web, visit: 
http://www.nasa.gov/home 

http://www.nasa.gov/home 
	
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