Cassini Finds Plethora of Plumes, Hotspots on Saturn's Moon Enceladus

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ScienceDaily (Feb. 24, 2010) — Newly released images from last November's swoop over Saturn's icy moon Enceladus by NASA's Cassini spacecraft reveal a forest of new jets spraying from prominent fractures crossing the south polar region and yield the most detailed temperature map to date of one fracture.

The new images from the imaging science subsystem and the composite infrared spectrometer teams also include the best 3-D image ever obtained of a "tiger stripe," a fissure that sprays icy particles, water vapor and organic compounds. There are also views of regions not well-mapped previously on Enceladus, including a southern area with crudely circular tectonic patterns.

The images and additional information are online at http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov.

"Enceladus continues to astound," said Bob Pappalardo, Cassini project scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "With each Cassini flyby, we learn more about its extreme activity and what makes this strange moon tick."

http://www.sciencedaily.com/releases/2010/02/100223162707.htm


In this unique mosaic image combining high-resolution data from the imaging science subsystem and composite infrared spectrometer aboard NASA's Cassini spacecraft, pockets of heat appear along one of the mysterious fractures in the south polar region of Saturn's moon Enceladus. The fracture, named Baghdad Sulcus, is one of the so-called "tiger stripe" features that erupt with jets of water vapor and ice particles. It runs diagonally across the image.

This mosaic, obtained on Nov. 21, 2009, shows a 40-kilometer (25-mile) segment of Baghdad Sulcus and illustrates the correlation between the geologically youthful surface fractures and anomalously warm temperatures recorded in the south polar region. It shows the highest-resolution data yet of the heat leaking from the moon's interior along the tiger stripes.

The image shows that broad swaths of heat previously detected by the infrared spectrometer are confined to a narrow, intense region no more than a kilometer (half a mile) wide along the fracture. The thermal image also reveals that the strength of the thermal radiation varies considerably along the length of this fissure segment. The temperature along Baghdad Sulcus reached more than 180 Kelvin (about minus 140 degrees Fahrenheit).

This mosaic layers temperature data atop of a visible-light image and alignment of the two data sets is approximate. The mosaic is centered near 80 degrees south latitude and 30 degrees west longitude. The V-shaped valleys that distinguish Baghdad are about 500 meters (1,600 feet) deep. The 30-degree slopes that rise along the valleys appear to be coated with smooth-looking particulate deposits that are peppered with large ice blocks that can reach tens of meters (yards) in size. The smooth materials most likely represent ice grain fallout from active jets that erupt along this warm and active section of Baghdad. The ice blocks appear to be icy rubble that may have been exposed by scouring from the eruptions, seismic shaking, and down-slope settling of the finer ice particles.
http://www.nasa.gov/mission_pages/cassini/multimedia/pia11696-b.html