On Oct. 5, 2008, just after coming within 25 kilometers (15.6 miles)
of the surface of Enceladus, NASA's Cassini captured this stunning
mosaic as the spacecraft sped away from this geologically active moon of
Saturn.
Craters and cratered terrains are rare in this view of the southern
region of the moon's Saturn-facing hemisphere. Instead, the surface is
replete with fractures, folds, and ridges—all hallmarks of remarkable
tectonic activity for a relatively small world. In this enhanced-color
view, regions that appear blue-green are thought to be coated with
larger grains than those that appear white or gray.
Portions of the tiger stripe fractures, or sulci, are visible along the
terminator at lower right, surrounded by a circumpolar belt of
mountains. The icy moon's famed jets emanate from at least eight
distinct source regions, which lie on or near the tiger stripes.
However, in this view, the most prominent feature is Labtayt Sulci, the
approximately one-kilometer (0.6 miles) deep northward-trending chasm
located just above the center of the mosaic.
Near the top, the conspicuous ridges are Ebony and Cufa Dorsae. This
false-color mosaic was created from 28 images obtained at seven
footprints, or pointing positions, by Cassini's narrow-angle camera. At
each footprint, four images using filters sensitive to ultraviolet,
visible and infrared light (spanning wavelengths from 338 to 930
nanometers) were combined to create the individual frames. The mosaic is
an orthographic projection centered at 64.49 degrees south latitude,
283.87 west longitude, and it has an image scale of 196 kilometers
(122.5 miles) per pixel. The original images ranged in resolution from
180 meters (594 feet) to 288 meters (950 feet) per pixel and were
acquired at distances ranging from 30,000 to 48,000 kilometers (18,750
to 30,000 miles) as the spacecraft receded from Enceladus. The view was
acquired at a Sun-Enceladus-spacecraft, or phase, angle of 73 degrees.
Image: NASA/JPL/Space Science Institute [high-resolution]
Caption: NASA
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