A set of three parallel ridges was seen by the Cassini spacecraft's radar
instrument during the latest Titan flyby on May 12, 2008. This combination
is unlikely to be a coincidence -- the best explanation for these features
is that they are tilted or separated blocks of broken or faulted crust,
now exposed as high ridges. Their regular spacing is typical of regions
that have been compressed or extended over large areas; as an example, the
western United States Basin and Range Province was formed by extension.
Such interactions are called tectonics, although they do not happen in the
same way as plate tectonics, which is a process unique to Earth.
The ridges, which appear on the left side of the image, are rugged
features and are elevated above surrounding terrain. The brightness
patterns mean that the materials are fractured or blocky at the radar
wavelength (2.17 centimeters, or about 1 inch). Along the south sides of
the ridges are prominent cliffs, or scarps, present as thin, radar-dark
lines trending west-to-east, and interpreted as faults. These features are
dark due to shadowing from the radar illumination, and have heights up to
a few hundred meters (several hundred feet), based on preliminary
estimates of slopes.
The area shown here is located in the mountainous region called Xanadu.
The ridges are similar in many ways to mountain chains seen at similar
latitude but about 90 degrees to the west, just west of Shangri-La
(observed during a flyby in October 2005, PIA08454). Both regions have mountain
chains or ridges that are oriented west-to-east and are spaced about 50
kilometers (30 miles) apart. This indicates tectonic forces have acted in
a north to south direction at Titan's equatorial region and have resulted
in regular effects in Titan's crust, evidence that will help scientists
better understand Titan's crust and interior.
Other linear features, probably related to the formation of the ridges,
and circular features, perhaps eroded impact craters now filled with
radar-dark (smooth) material, are also seen in the image. The largest
circular feature, at bottom center, is about 20 km in diameter.
The image is centered at 2 degrees south, 127 degrees west and was
obtained on May 12, 2008, with a resolution of about 300 meters (980
feet). The open arrow indicates the direction of radar illumination. The
dashed white line in the upper portion is an artifact of the SAR
processing and will be removed in later versions.
The Cassini-Huygens mission is a cooperative project of NASA, the European
Space Agency and the Italian Space Agency. NASA's 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 was designed, developed and assembled
at JPL. The radar instrument was built by JPL and the Italian Space
Agency, working with team members from the United States and several
European countries.
For more information about the Cassini-Huygens mission visit
http://saturn.jpl.nasa.gov/.
