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Phoebe flyby preview
This animation shows Cassini during its encounter with the tiny moon Phoebe on the route to Saturn. (42sec file)
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Cassini preview
The Cassini spacecraft's arrival at Saturn is previewed in this detailed news conference from NASA Headquarters on June 3. (50min 01sec file)
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Saturn arrival explained
Cassini's make-or-break engine firing to enter orbit around Saturn is explained with graphics and animation. Expert narration is provided by Cassini program manager Robert Mitchell. (3min 33sec file)
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Cassini mission science
The scientific objectives of the Cassini mission to study the planet Saturn, its rings and moons are explained by Charles Elachi, director of the Jet Propulsion Laboratory. (4min 54sec file)
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Huygens mission science
After entering orbit around Saturn, the Cassini spacecraft will launch the European Huygens probe to make a parachute landing on the surface of the moon Titan. The scientific objectives of Huygens are explained by probe project manager Jean-Pierre Lebreton. (3min 14sec file)
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Saturn's moon Phoebe revealed in stunning detail
CASSINI PHOTO RELEASE
Posted: June 13, 2004

Extraordinary new images taken by the Cassini spacecraft during its close encounter with Saturn's mysterious moon Phoebe were released by scientists Sunday. The must-see pictures show in great detail the cratered surface of the tiny moon.


Credit: NASA/JPL/Space Science Institute
Download larger image version here

 
FIRST IMAGE: Phoebe's true nature is revealed in startling clarity in this mosaic of two images taken during Cassini's flyby on June 11, 2004. The image shows evidence for the emerging view that Phoebe may be an ice-rich body coated with a thin layer of dark material. Small bright craters in the image are probably fairly young features. This phenomenon has been observed on other icy satellites, such as Ganymede at Jupiter. When impactors slammed into the surface of Phoebe, the collisions excavated fresh, bright material -- probably ice -- underlying the surface layer. Further evidence for this can be seen on some crater walls where the darker material appears to have slid downwards, exposing more light-colored material. Some areas of the image that are particularly bright - especially near lower right - are over-exposed.

An accurate determination of Phoebe's density - a forthcoming result from the flyby - will help Cassini mission scientists understand how much of the little moon is comprised of ices.

This spectacular view was obtained at a phase, or Sun-Phoebe-spacecraft, angle of 84 degrees, and from a distance of approximately 32,500 kilometers (20,200 miles). The image scale is approximately 190 meters (624 feet) per pixel. No enhancement was performed on this image.


Credit: NASA/JPL/Space Science Institute
Download larger image version here

 
SECOND IMAGE: Phoebe delivers on its promise to reveal new wonders to Cassini by showing probable evidence of an ice-rich body overlain with a thin layer of dark material. The sharply-defined crater at above center exhibits two or more layers of alternating bright and dark material. Imaging scientists on the Cassini mission have hypothesized that the layering might occur during the crater formation, when ejecta thrown out from the crater buries the pre-existing surface that was itself covered by a relatively thin, dark lag deposit over an icy mantle. The lower thin dark layer on the crater wall appears to define the base of the ejecta blanket. The ejecta blanket itself appears to be mantled by a more recent dark surface lag.

This image was obtained on June, 11 2004 at a phase, or Sun-Phoebe-spacecraft, angle of 79 degrees, and from a distance of 13,377 kilometers (8,314 miles). The image scale is approximately 80 meters (263 feet) per pixel. No enhancement was performed on this image.


Credit: NASA/JPL/Space Science Institute
Download larger image version here

 
THIRD IMAGE:This eye-popping high-resolution image of Phoebe's pitted surface taken very near closest approach shows a 13-kilometer (8-mile) diameter crater with a debris-covered floor. Part of another crater of similar size is visible at left, as is part of a larger crater at top and many scattered smaller craters. The radial streaks in the crater are due to downslope movements of loose fragments from impact ejecta. Also seen are boulders ranging from about 50 to 300 meters (160 to 990 feet) in diameter. The building-sized rocks may have been excavated by large impacts, perhaps from some other region of Phoebe rather than the craters seen here. There is no visible evidence for layering of ice and regolith or a hardened crust in this region, as on other parts of this moon.

Some of the relatively bright spots are from small impacts that excavated bright material from beneath the dark surface. Images like this provide information about impact and regolith processes on Phoebe.

This image was obtained at a phase, or Sun-Phoebe-spacecraft, angle of 78 degrees, and from a distance of 11,918 kilometers (7,407 miles). The image scale is approximately 18.5 meters (60.5 feet) per pixel. The illumination is from the right. No enhancement was performed on this image.

Ares 1-X Patch
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Apollo Collage
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Expedition 21
The official embroidered patch for the International Space Station Expedition 21 crew is now available from our stores.
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The official embroidered patch for mission STS-125, the space shuttle's last planned service call to the Hubble Space Telescope, is available for purchase.
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