This side-by-side view shows a newly discovered impact crater (at left)
compared with a previously discovered crater (at right). The new crater
was just discovered by the Cassini spacecraft's radar instrument during
its most recent Titan flyby on May 12, 2008. This makes the fourth feature
definitely identified as an impact crater so far on Titan -- fewer than
100 features are regarded as possible impacts. Compared with Saturn's
other moons, which have many thousands of craters, Titan's surface is very
sparsely cratered. This is in part due to Titan's dense atmosphere, which
burns up the smaller impacting bodies before they can hit the surface.
Geological processes, such as wind-driven motion of sand and icy
volcanism, may also wipe out craters.
Both images are about 350 kilometers (217 miles) in width. The crater on
the right was discovered by Cassini in 2005 and is shown here for
comparison. It is 80 kilometers (50 miles) in diameter (see PIA07368), with the
radar illumination from above. Called Sinlap, this crater is estimated to
be about 1,300 meters (4300 feet) deep. The new feature pictured on the
left, which has not been named yet, is bigger than the Sinlap crater with
a diameter of about 112 kilometers (70 miles).
The new crater is located at about 26 degrees north latitude, 200 degrees
west longitude, in the bright region known as Dilmun, about 1,000
kilometers (600 miles) north of the Huygens landing site. In its image,
also illuminated from above, it appears slightly irregular, suggesting
that it was modified after it was formed, perhaps by collapses of segments
of its rim onto the floor. The crater floor appears flat, and two small
bright spots indicate a likely central peak complex. The ejecta blanket
(surrounding material) from this crater is less prominent than that of the
Sinlap crater. The crater's more degraded character suggests it could be
older than Sinlap (assuming that erosive processes are the same at both
locations, which are at similar latitudes).
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/.
