Following its last close flyby of Saturn's moon Rhea, NASA's Cassini spacecraft captured these raw, unprocessed images of the battered icy moon. They show an ancient, cratered surface bearing the scars of collisions with many space rocks. Scientists are still trying to understand some of the curious features they see in these Rhea images, including a curving, narrow fracture or a graben, which is a block of ground lower than its surroundings and bordered by cliffs on either side. This feature looks remarkably recent, cutting most of the craters it crosses, with only a few small craters superimposed. Read more
These raw, unprocessed images of Saturn's second largest moon, Rhea, were taken on March 10, 2012, by NASA's Cassini spacecraft. This was a relatively distant flyby with a close-approach distance of 42,000 kilometres, well suited for global geologic mapping. During the flyby, Cassini captured these distinctive views of the moon's cratered surface, creating a 30-frame mosaic of Rhea's leading hemisphere and the side of the moon that faces away from Saturn. The observations included the large Mamaldi (480 kilometres, across) and Tirawa (360 kilometres, across) impact basins and the 47-kilometers ray crater Inktomi, one of the youngest surface features on Rhea (about 1,530 kilometres, across). Read more
This global digital map of Rhea was created using data taken during Cassini and Voyager spacecraft flybys. The map is an equidistant projection and has a scale of 417 meters per pixel in the full size version. The mean radius of Rhea used for projection of this map is 764.1 kilometers.
Expand (5.45mb, 11520 x 5760) Credit: NASA/JPL/Space Science Institute
NASA's Cassini spacecraft has successfully completed its closest flyby of Saturn's moon Rhea, returning raw images of the icy moon's surface. Pictures of the Rhea surface taken around the time of closest approach at 4:53 a.m. UTC on Jan. 11, 2011, which was 10:53 p.m. PST, Jan. 10, show shadowy craters at a low sun angle. A portrait of bright, icy Rhea also captures Saturn's rings and three other moons clearly visible in the background. Images obtained by Cassini's imaging science subsystem show an old, inert surface saturated with craters, just like the oldest parts of Earth's moon. But there appear to be some straight faults that were formed early in Rhea's history, which never developed the full-blown activity seen on another of Saturn's moons, Enceladus. Read more
Saturn's icy moon Rhea might seem a strange place to look for clues to understanding the vast majestic rings encircling Saturn. But that's what NASA's Cassini spacecraft plans to do on its next flyby of Rhea. At closest approach, Cassini will pass within about 69 kilometres of the surface at 4:53 AM UTC on Tuesday, Jan. 11, which is 10:53 PM Pacific Time on Monday, Jan. 10. This flyby is the closest Cassini will get to the icy moon's surface. Read more
DLR researchers compile atlas of Saturn's moon Rhea
Researchers at the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) have compiled an atlas of Saturn's second largest moon, Rhea, which has been published by NASA today. The atlas includes a number of high-resolution images and a three-dimensional view of fractures on the icy world acquired by the Cassini spacecraft, which has been orbiting Saturn for six and a half years. The data was obtained during two fly-bys in September 2009 and March 2010, from distances as close as 100 kilometres. The atlas comprises the most detailed images of Rhea to date and provides an insight into the geological development and surface composition of the moon. Recently, two instruments on Cassini discovered a thin oxygen-carbon dioxide atmosphere, or exosphere, on Rhea. Read more
Cassini Marks Holidays With Dramatic Views of Rhea
Newly released for the holidays, images of Saturn's second largest moon Rhea obtained by NASA's Cassini spacecraft show dramatic views of fractures cutting through craters on the moon's surface, revealing a history of tectonic rumbling. The images are among the highest-resolution views ever obtained of Rhea. Read more