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Saturn Details Become Visible To Cassini Spacecraft

One year since last sighting Saturn, and less than eight months before reaching the planet, the cameras on NASA's Cassini spacecraft have caught another glimpse of the ringed planet, growing more detailed with time.

A natural color composite of the image is available from the Cassini Imaging Team's website and from NASA's Jet Propulsion Laboratory's Planetary Photojournal.

The planet was 111 million kilometers (69 million miles) from the spacecraft when the images were taken last week, about the equivalent of three-fourths of the distance between Earth and the Sun. The image shows details in the rings and atmosphere not seen a year ago, as well as five of Saturn's icy moons.

"After more than a decade of preparation and waiting for arrival, it is satisfying to see the Saturnian moons in this approach picture," said Dr. Gerhard Neukum, an imaging team member and a professor at Free University in Berlin, Germany. "Soon we will be in orbit around Saturn to investigate these worlds in detail and to decipher their geologic history from close-up images - an exciting prospect."

Dr. Anthony Del Genio, imaging team member from NASA Goddard Institute for Space Studies in New York City and a specialist in atmospheric studies, said, "We can only see the general banded structure of Saturn from this distance, but we know that as we get closer those bands will break up before our eyes into smaller features - spots, storms, wave patterns that we'll be able to see in 10 times more detail than any previous observation of Saturn.

"I can't wait to dive in as we see it all unfold over the next few months. For all of us who have worked for more than a decade preparing for this mission, seeing Saturn grow larger and larger in the eyes of the Cassini cameras is a bit like the feelings children have as they come downstairs on Christmas morning to see what gifts are waiting for them under the tree," Del Genio said. "But this Christmas will last for four years."

Dr. Carolyn Porco, a planetary ring specialist and leader of the Imaging Science team, said, "For someone who was involved in the Voyager exploration of Saturn twenty-three years ago, this is turning out to be a very sentimental journey. I'm reminded of what it felt like to see Saturn's rings for the first time with Voyager, and how rich and surprising they were. The spokes in the B ring, the twisted F ring and its shepherding moons, the sheer number and diversity of ring features... we'll be on the lookout for all these things and more over the next few months".

Dr. Wesley Huntress, former Cassini Study Scientist in the mid-1980s, Director of NASA's Solar System Exploration Division in 1990 at the inception of the Cassini mission, and presently the Director of Carnegie Institution of Washington's Geophysical Laboratory, said of the latest image, "Wow! So far away, so long to travel, so much effort to make it happen, and so worth it".

Fourteen camera-team scientists from the United States and Europe will use the two cameras on Cassini to investigate many features of Saturn, its moons and its rings. Cassini will begin a four-year prime mission in orbit around Saturn when it arrives on July 1, 2004. It will release its piggybacked Huygens probe about six months later for descent through the thick atmosphere of the moon Titan. The probe could impact in what may be a liquid methane ocean.

The Cassini-Huygens mission is a cooperative mission of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Office of Space Science, Washington, D.C.

The Space Science Institute, home to the Cassini Imaging Central Laboratory for Operations, is a non-profit organization of scientists and educators engaged in research in the areas of astrophysics, planetary science and the earth sciences, and in integrating research with education and public outreach.

Mission information is available online at saturn.jpl.nasa.gov.

Media Contact

Heidi Finn, (720) 974-5859, Cassini Imaging Central Laboratory for Operations, Space Science Institute, Boulder, CO

This article was derived from the NASA Jet Propulsion Laboratory Press Release.

   

Cassini image of Saturn. See following caption.

Saturn, Nov. 9, 2003
A cold, dusky Saturn looms in the distance in this striking, natural color view of the ringed planet and five of its icy satellites. This image was composed from exposures taken by Cassini's narrow angle camera on Nov. 9, 2003, from a distance of 111.4 million kilometers (69.2 million miles). That is about three-fourths the distance of Earth from the Sun and 235 days from reaching Saturn. The smallest features visible here are about 668 kilometers (415 miles) across - a marked improvement over the last Cassini Saturn image released on Nov. 1, 2002. New features such as intricate cloud patterns and small moons near the rings should become visible over the next several months as the spacecraft speeds toward its destination.

Some details within Saturn's massive ring system are already visible. Structure is evident in the B ring, the middle and brightest of Saturn's three main rings. The 4,800 kilometer (2,980 mile)-wide Cassini Division is the distinctive dark, central band that separates the outermost A ring from the brighter B ring. Interestingly, the outer edge of the B ring is maintained by a strong gravitational resonance with the moon Mimas, also visible in this image. The 325-kilometer (200 -mile) wide Encke gap in the A ring, near the outer edge of the ring system, is also visible, as is the fainter C ring, interior to the B ring.

Saturn's multi-banded, multi-hued atmosphere is also apparent at this distance. In the southern polar region, a dusky haze is visible, grayer than the light-brown at middle latitudes. Most of Saturn's northern hemisphere is in shadow of the rings, with the exception of a small sliver visible on the limb. Five Saturnian satellites can also be seen in this image. The brightness of these bodies has been increased three- to five-fold to enhance visibility. The satellites are, on the left, from brightest to faintest, Rhea, Dione, and Enceladus, and on the right, from brightest to faintest, Tethys and Mimas. Credit: NASA/JPL/Space Science Institute