Close Up of Enceladus' Tiger Stripes. Image Credit: Paul Shenk (LPI), USRA; Cassini Imaging Team, SSI, JPL, ESA, NASA

Saturn and Titan from Cassini. Image Credit: Cassini Imaging Team, SSI, JPL, ESA, NASA

Heat radiating from the entire length of 150 kilometer (95 mile)-long fractures is seen in this best-yet heat map of the active south polar region of Saturn's ice moon Enceladus. The warmest parts of the fractures tend to lie on locations of the plume jets identified in earlier images, shown in the annotated version with yellow stars. The measurements were obtained by the Cassini spacecraft's Composite Infrared Spectrometer from the spacecraft's close flyby of the moon on March 12, 2008.

Remarkably high temperatures, at least 180 Kelvin (minus 135 degrees Fahrenheit) were registered along the brightest fracture, named Damascus Sulcus, in the lower left portion of the image. For comparison, surface temperatures elsewhere in the south polar region of Enceladus are below 72 Kelvin (minus 330 degrees Fahrenheit).

Heat is escaping from Enceladus' interior along these warm fractures, dubbed "tiger stripes," which are also the source of the geysers that erupt from the polar region. The infrared radiation was mapped at wavelengths between 12 and 16 microns. The infrared data, shown in false color, are superimposed on a grayscale image mosaic of the south pole obtained by Cassini's cameras on July 14, 2005, during the previous close Enceladus flyby. Numbers on the map indicate latitude and longitude.

This new view shows that at least three of the south polar fractures are active along almost their full lengths--the fourth one, on the right, was only partially covered by this scan. The level of activity varies greatly along the fractures. The warmest parts of the fractures tend to lie on locations of the plume jets identified in earlier images. The main "tiger stripe" fractures are not the only sources of heat, however; additional warm spots are seen in the upper right part of the scan. The warm regions are probably concentrated within less than a few hundred meters (a few hundred yards) of the fractures, and their apparent width in this image results from the relatively low resolution of the infrared data.

This map was made by scanning the south pole during the period from 16 to 37 minutes after closest approach to Enceladus, at a distance between 14,000 and 32,000 kilometers (about 8,700 and 20,000 miles) as Cassini rapidly receded from its close (50-kilometer or 32-mile) flyby. Image Credit: NASA/JPL/Space Science Institute

Thirty Thousand Kilometers Above Enceladus. Image Credit: Cassini Imaging Team, SSI, JPL, ESA, NASA

Bright Blue marks a deposit of chloride (salt) minerals in the southern highlands of Mars in this THEMIS false-color image which highlights mineral composition differences. Using THEMIS, researchers have found more than 200 such features. These deposits typically lie within topographic depressions and suggest that Mars was much wetter long ago. The black rectangle shows the outline of a closeup view (below); 10 kilometers equals 6.2 miles. Image credit: NASA/JPL/Arizona State University/University of Hawaii

This graphic and animation depicts a cross-section of the Saturnian moon Titan. Cassini scientists speculate there may be a layer of liquid water mixed with ammonia about 100 kilometers (62 miles) below the surface of Titan.

The assumption that Titan contains an internal ocean was generated from data gleaned from Cassini's Synthetic Aperture Radar during 19 separate passes over Titan between October 2005 and May 2007. Using data from the radar's early observations, the scientists and radar engineers established the locations of 50 unique landmarks on Titan's surface. They then searched for these same lakes, canyons and mountains in the reams of data returned by Cassini in its later flybys of Titan. What they found was prominent surface features seemed to shift from their expected positions by up to 31 kilometers (19 miles). Since the features could not have really moved, the apparent shift told the scientists and engineers that Titan was spinning about its axis in a previously unsuspected manner. The pre-Cassini model of Titan's spin accounted for the gravitational fields of Saturn and other nearby planets and moons but omitted other smaller less well understood effects. Since the observed spin of Titan does not fit this model, other influences, such as the seasonal changes in the motion of its atmosphere must also be important. It is difficult to explain how such relatively low energy phenomena could have such a pronounced influence on Titan's spin unless the moon's icy crust was decoupled from its core by an internal ocean. If the crust were decoupled from the core, atmospheric fluctuation alone could account the observed spin. Image credit: NASA/JPL

Space shuttle Endeavour lifts off its launch pad at 2:28 a.m. EDT to start the STS-123 mission to the International Space Station. Credit: NASA/Jim Grossmann

This false-color view was created by combining three clear filter images taken at nearly the same time as PIA07759. This image product was then specially processed to enhance the individual jets that compose the plume. (PIA07759 was instead processed to reveal subtleties in the brightness of the overall plume that comprises the jets.) Some artifacts due to the processing are present in the image. The final product was colored as blue for dramatic effect. Image Credit: NASA/ JPL/ Space Science Institute

This is an artist concept of the ring of debris that may orbit Saturn's second-largest moon, Rhea. The suggested disk of solid material is exaggerated in density here for clarity. Image Credit: NASA/JPL/JHUAPL

GLAST unwrapped at the Naval Research Laboratory! The Large Area Space Telescope instrument is the large silver "box" that sits atop the satellite. Credit: NRL

Four Martian Avalanches in Action

The crew of STS-123 stands in front of space shuttle Endeavour, the spacecraft they will fly into space for the mission. Photo credit: NASA/Kim Shiflett

This artist's concept depicts NASA's Phoenix Mars Lander a moment before its 2008 touchdown on the arctic plains of Mars. Pulsed rocket engines control the spacecraft's speed during the final seconds of descent. Image credit: NASA/JPL-Calech/University of Arizona

While designing the lunar truck, JSC engineers threw out some traditional assumptions on what a vehicle needs -- for instance, doors and seats -- and added interesting new capabilities such as active suspension, six-wheel drive with independent steering for each wheel. Credit: NASA

Digital Elevation Map of Lunar South Pole -- Image brightness is generated from the strength of the radar echoes that are bounced of the lunar surface and the color represents the elevation. This map covers an area of 650 kilometers by 450 kilometers with an elevation measurement every 40 meters. Image Credit: NASA/JPL

Opportunity View of 'Gilbert' Layer (False Color)