Figure 1: Originally Released Image
This spectacular view is a mosaic of four high resolution images taken by
the Cassini spacecraft narrow angle camera on Feb. 16, 2005, during its
close flyby of Saturn's moon Enceladus.
The view is about 300 kilometers (200 miles) across and shows the myriad
of faults, fractures, folds, troughs and craters that make this Saturnian
satellite especially intriguing to planetary scientists. More than 20
years ago, NASA's Voyager spacecraft gave hints of a surface cut by
tectonic features, and subsequent images of other icy moons have revealed
many different ways that stresses have acted on icy moon crusts.
The new close-up images of Enceladus, which has a diameter of 505
kilometers (314 miles), show some familiar-looking features and others
that are brand new. The work required to unravel their origins, their
formation sequence, and the implications for the evolution of icy solar
system bodies is just beginning.
Voyager images of Enceladus, which were obtained at much poorer spatial
resolution, showed terrains like those seen here. They were called "smooth
plains" because they appeared to exhibit little topographic relief.
However, Cassini has now viewed these terrains at almost 10 times better
resolution. The new images reveal very complex systems of fractures,
resurfaced terrain, and in some cases, topographic relief greater than
several hundred meters.
Many styles of fracturing are evident in this mosaic. Extending downward
from the top center of the mosaic for hundreds of kilometers is a broad
belt of complex, interwoven fractures. A huge rift 5 kilometers (3
miles)-wide dissects this belt and extends into several older-looking,
distinct regions or "cells" of terrain that themselves exhibit distinct
fracture patterns.
Because Cassini flew rapidly past Enceladus, the right-side images were
taken from a slightly different perspective than the left, and are
delineated by the white box.
The mosaic covers longitudes from about 254 west to 296 west and
latitudes from 60 south to the equator.
The images were taken in visible light on Feb. 17, 2005, at distances
ranging from of 26,140 to 17,434 kilometers (16,243 to 10,833 miles) from
Enceladus and at Sun-Enceladus-spacecraft, or phase, angles ranging from
27 to 29 degrees. Pixel scale in the left-side image is 150 meters (492
feet) per pixel; in the right-side (white box) image, scale is 105 meters
(344 feet) per pixel. The image has been contrast-enhanced to aid
visibility.
The Cassini-Huygens mission is a cooperative project of NASA, the
European Space Agency and the Italian Space Agency. The Jet Propulsion
Laboratory, a division of the California Institute of Technology in
Pasadena, manages the mission for NASA's Science Mission Directorate,
Washington, D.C. The Cassini orbiter and its two onboard cameras were
designed, developed and assembled at JPL. The imaging team is based at
the Space Science Institute, Boulder, Colo.
For more information about the Cassini-Huygens mission, visit
http://saturn.jpl.nasa.gov and the Cassini imaging team home page,
http://ciclops.org.
