Cassini, Saturn Moon Photographer

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http://www.jpl.nasa.gov/news/news.cfm?release=2012-123

Cassini, Saturn Moon Photographer
Jet Propulsion Laboratory
May 02, 2012

NASA's Cassini spacecraft successfully flew by Saturn's moons Enceladus
and Dione during close flybys on May 2, 2012, capturing these raw
images. The flybys were the last close encounters of these icy moons
that Cassini will make for three years.

Cassini flew by Enceladus at an altitude of about 46 miles (74
kilometers). This flyby was designed primarily for the radio science
sub-system to measure variations in Enceladus' gravity field.

On approach to Enceladus, Cassini's cameras imaged the icy satellite's
south polar plume, which consists of jets of water ice, water vapor and
organic compounds sprayed into space from the moon's famed "tiger
stripe" fractures. The plume images were captured at distances ranging
from 259,000 miles (416,000 kilometers) down to 66,000 miles (106,000
kilometers) when Enceladus was just a thin crescent and the plume was
backlit.

During closest approach, the radio science team looked for a
concentration of mass at the south pole that could indicate sub-surface
liquid water or an intrusion of warmer-than-average ice that might
explain the intriguing geologic activity at the south pole. After the
closest approach, the composite infrared spectrometer obtained a map of
Enceladus' sun-lit side while Cassini's visible light cameras rode along
and captured several images of the moon's leading hemisphere at
resolutions of about 1,500 feet (450 meters) per pixel.

Later this month, a close encounter with Titan on May 22 will pitch the
spacecraft up out of the equatorial plane and into a nearly
three-year-long phase of inclined orbits that will showcase the northern
and southern reaches of Saturn. On March 9, 2013, Cassini will make a
close pass by Rhea, but the spacecraft won't have another close,
targeted encounter with any of Saturn's other icy satellites until June
2015, when it encounters Dione. Cassini will make its next flyby of
Enceladus on Oct. 14, 2015.

For information about Cassini, visit: 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. NASA's Jet
Propulsion Laboratory, Pasadena, Calif., manages the mission for NASA's
Science Mission Directorate, Washington, D.C. The imaging team is based
at the Space Science Institute, Boulder, Colo. JPL is a division of the
California Institute of Technology, Pasadena.

Jia-Rui C. Cook 818-354-0850
Jet Propulsion Laboratory, Pasadena, Calif.
jia-rui...@jpl.nasa.gov

2012-123