The Story Titan's Dunes Tell

An intricate, fingerprint-like pattern of dunes is seen in this dramatic radar image of Saturn's moon Titan captured by NASA's Cassini spacecraft on May 21, 2009 from an altitude of 965 kilometers (about 600 miles). The dunes likely consist of sand-sized particles made of organic material.

On Earth, dunes preferentially form in low-lying regions as hills or mountains present an obstacle to the movement of sand-sized particles. The general absence of dunes on the bright patches seen here supports the notion that they are likely topographically high regions or mountains that block the dunes. The forked tongue of dunes crossing the bright patch at right may have formed in a relatively low-lying valley in the bright terrain.

The significant variations in spacing and density of the dunes indicate a variation in the sand supply and/or local differences in winds at the surface. The dunes are roughly symmetrical around the irregular bright region in the left half of the image, suggesting that the bright region is somehow responsible for creating the pattern.

The area imaged is 225 by 636 kilometers (140 by 395 miles), centered just north of the equator at 0.5 deg N latitude, 154.2 degrees W longitude. Radar illumination is from the top at an incidence angle of 24 degrees. North is to the right in this image. The obvious horizontal stripes across the center and top of this preliminary version are artifacts of the way the image is produced.

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/index.cfm.