The slim crescent of Iapetus looms before the Cassini spacecraft as it
approaches the mysterious moon.
Iapetus, 1,468 kilometers (912 miles) across, seen here in false color, is
unique in its dramatic variation in brightness between the northern polar
region and the middle and low latitudes. Equally prominent is the moon's
equatorial ridge of towering mountains. The profile of the ridge against
the darkness of space reveals that it is topped by a cratered plateau
approximately 15 kilometers (9 miles) wide. Further west, the profile of
the ridge changes from a long plateau to discrete peaks.
The mosaic consists of four image footprints across the surface of Iapetus
and has a resolution of 489 meters (0.3 miles) per pixel.
A full-resolution clear filter image was combined with half-resolution
images taken with infrared, green and ultraviolet spectral filters
(centered at 752, 568 and 338 nanometers, respectively) to create this
full-resolution false color mosaic.
The color seen in this view represents an expansion of the wavelength
region of the electromagnetic spectrum visible to human eyes. The intense
reddish-brown hue of the dark material is far less pronounced in true
color images. The use of enhanced color makes the reddish character of the
dark material more visible than it would be to the naked eye. In addition,
the scene has been brightened to improve the visibility of surface
features.
This view was acquired with the Cassini spacecraft narrow-angle camera on
Sept. 10, 2007, at a distance of about 83,000 kilometers (51,600 miles)
from Iapetus.
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 operations center is based at the Space
Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit
http://saturn.jpl.nasa.gov/home/index.cfm. The Cassini imaging
team homepage is at http://ciclops.org.
