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Tuesday 15 April 2008

NASA Extends Cassini's Grand Tour of Saturn

MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109 TELEPHONE 818-354-5011
http://www.jpl.nasa.gov

Dwayne Brown 202-358-1726
NASA Headquarters, Washington
dwayne.c.brown@nasa.gov

Carolina Martinez 818-354-9382
Jet Propulsion Laboratory, Pasadena, Calif.
carolina.martinez@jpl.nasa.gov

NEWS RELEASE: 2008-060                                  April 15, 2008

NASA Extends Cassini's Grand Tour of Saturn

PASADENA, Calif. -- NASA is extending the international Cassini-Huygens mission by two
years. The historic spacecraft's stunning discoveries and images have revolutionized our
knowledge of Saturn and its moons.

Cassini's mission originally had been scheduled to end in July 2008. The newly-announced two-
year extension will include 60 additional orbits of Saturn and more flybys of its exotic moons.
These will include 26 flybys of Titan, seven of Enceladus, and one each of Dione, Rhea and
Helene. The extension also includes studies of Saturn's rings, its complex magnetosphere, and
the planet itself.

"This extension is not only exciting for the science community, but for the world to continue to
share in unlocking Saturn's secrets," said Jim Green, director, Planetary Science Division, NASA
Headquarters, Washington. "New discoveries are the hallmarks of its success, along with the
breathtaking images beamed back to Earth that are simply mesmerizing."

"The spacecraft is performing exceptionally well and the team is highly motivated, so we're
excited at the prospect of another two years," said Bob Mitchell, Cassini program manager at
NASA's Jet Propulsion Laboratory in Pasadena, Calif.

Based on findings from Cassini, scientists think liquid water may be just beneath the surface of
Saturn's moon Enceladus. That's why the small moon, only one-tenth the size of Titan and one-
seventh the size of Earth's moon, is one of the highest-priority targets for the extended mission.

Cassini discovered geysers of water-ice jetting from the Enceladus surface. The geysers, which
shoot out at a distance three times the diameter of Enceladus, feed particles into Saturn's most
expansive ring. In the extended mission, the spacecraft may come as close as 25 kilometers (15
miles) from the moon's surface.

Cassini's observations of Saturn's largest moon, Titan, have given scientists a glimpse of what
Earth might have been like before life evolved. They now believe Titan possesses many parallels
to Earth, including lakes, rivers, channels, dunes, rain, snow, clouds, mountains and possibly
volcanoes.

"When we designed the original tour, we really did not know what we would find, especially at
Enceladus and Titan," said Dennis Matson, the JPL Cassini project scientist. "This extended tour
is responding to these new discoveries and giving us a chance to look for more."

Unlike Earth, Titan's lakes, rivers and rain are composed of methane and ethane, and
temperatures reach a chilly minus 180 degrees Celsius (minus 290 degrees Fahrenheit). Although
Titan's dense atmosphere limits viewing the surface, Cassini's high-resolution radar coverage and
imaging by the infrared spectrometer have given scientists a better look.

Other activities for Cassini scientists will include monitoring seasons on Titan and Saturn,
observing unique ring events, such as the 2009 equinox when the sun will be in the plane of the
rings, and exploring new places within Saturn's magnetosphere.

Cassini has returned a daily stream of data from Saturn's system for almost four years. Its travel
scrapbook includes nearly 140,000 images, and information gathered during 62 revolutions
around Saturn, 43 flybys of Titan and 12 close flybys of the icy moons.

More than 10 years after launch and almost four years after entering into orbit around Saturn,
Cassini is a healthy and robust spacecraft. Three of its science instruments have minor ailments,
but the impact on science-gathering is minimal. The spacecraft will have enough propellant left
after the extended mission to potentially allow a third phase of operations. Data from the
extended mission could lay the groundwork for possible new missions to Titan and Enceladus.

Cassini launched Oct. 15, 1997, from Cape Canaveral, Fla., on a seven-year journey to Saturn,
traversing 3.5 billion kilometers (2.2 billion miles). It is one of the most scientifically capable
spacecraft ever launched, with a record 12 instruments on the orbiter and six more instruments
on the European Space Agency's Huygens probe, which piggybacked a ride to Titan on Cassini.
Cassini receives electrical power from three radioisotope thermoelectric generators, which
generate electricity from heat produced by the natural decay of plutonium. The spacecraft was
captured into Saturn orbit in June 2004 and immediately began returning data to Earth.

More information is available at: http://www.nasa.gov/cassini  and http://saturn.jpl.nasa.gov .

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 in
Pasadena, manages the Cassini-Huygens mission for NASA's Science Mission Directorate,
Washington. The Cassini orbiter was designed, developed and assembled at JPL.

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