The existence of oceans or lakes of liquid methane on Saturn's moon Titan
was predicted more than 20 years ago. But with a dense haze preventing a
closer look it has not been possible to confirm their presence. Until the
Cassini flyby of July 22, 2006, that is.
Radar imaging data from the flyby, published this week in the journal
Nature, provide convincing evidence for large bodies of liquid. This
image, used on the journal's cover, gives a taste of what Cassini saw.
Intensity in this colorized image is proportional to how much radar
brightness is returned, or more specifically, the logarithm of the radar
backscatter cross-section. The colors are not a representation of what the
human eye would see.
The lakes, darker than the surrounding terrain, are emphasized here by
tinting regions of low backscatter in blue. Radar-brighter regions are
shown in tan. The strip of radar imagery is foreshortened to simulate an
oblique view of the highest latitude region, seen from a point to its
west.
This radar image was acquired by the Cassini radar instrument in synthetic
aperture mode on July 22, 2006. The image is centered near 80 degrees
north, 35 degrees west and is about 140 kilometers (84 miles) across.
Smallest details in this image are about 500 meters (1,640 feet) across.
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 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/home/index.cfm.
