"During this, our tenth holiday season at Saturn, we hope that these images
from Cassini remind everyone the world over of the significance of our
discoveries in exploring such a remote and beautiful planetary system," said
Carolyn Porco, Cassini imaging team leader, based at the Space Science
Institute, Boulder, Colo. "Happy holidays from all of us on Cassini."
Two views of Enceladus are included in the package and highlight the many
fissures, fractures and ridges that decorate the icy moon's surface. Enceladus
is a white, glittering snowball of a moon, now famous for the nearly 100 geysers
that are spread across its south polar region and spout tiny icy particles into
space. Most of these particles fall back to the surface as snow. Some small
fraction escapes the gravity of Enceladus and makes its way into orbit around
Saturn, forming the planet's extensive and diffuse E ring. Because scientists
believe these geysers are directly connected to a subsurface, salty,
organic-rich, liquid-water reservoir, Enceladus is home to one of the most
accessible extraterrestrial habitable zones in the solar system.
Packaged along with Saturn and Enceladus is a group of natural-color images
of Saturn's largest moon, Titan, highlighting two of Titan's most outstanding
features. Peering through the moon's hazy, orange atmosphere, the Cassini
narrow-angle camera spots dark, splotchy features in the polar regions of the
moon. These features are the lakes and seas of liquid methane and ethane for
which the moon is renowned. Titan is the only other place in the solar system
that we know has stable liquids on its surface, though in Titan's case, the
liquids are ethane and methane rather than water. At Titan's south pole, a
swirling high-altitude vortex stands out distinctly against the darkness of the
moon's un-illuminated atmosphere. Titan's hazy atmosphere and surface
environment are believed to be similar in certain respects to the early
atmosphere of Earth.
But the planet that towers over these moons is a celestial wonder itself. The
north and south poles of Saturn are highlighted and appear drastically different
from each other, as seen in new natural-color views. The globe of Saturn
resembles a holiday ornament in a wide-angle image overlooking its north pole,
bringing into view the hexagonal jet stream and rapidly spinning polar vortex
that reside there. And the planet's south pole, now in winter, looking very
different than the springtime north, displays brilliant blue hues, reminiscent
of a frosty winter wonderland.
"Until Cassini arrived at Saturn, we didn't know about the hydrocarbon lakes
of Titan, the active drama of Enceladus' jets, and the intricate patterns at
Saturn's poles," said Linda Spilker, the Cassini project scientist at NASA's Jet
Propulsion Laboratory, Pasadena, Calif. "Spectacular images like these highlight
that Cassini has given us the gift of knowledge, which we have been so excited
to share with everyone."
Launched in 1997, Cassini has explored the Saturn system for more than nine
years. NASA plans to continue the mission through 2017, with the anticipation of
much more groundbreaking science and imagery to come.
The Cassini-Huygens mission is a cooperative project of NASA, the European
Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory (JPL),
a division of the California Institute of Technology in Pasadena, manages the
Cassini-Huygens mission for NASA's Science Mission Directorate, Washington.
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