This image shows Titan, Saturn's largest moon (5,150 kilometers, or 3,200 miles, across), with a streak-like cloud near its south pole. The cloud may be part of a region of polar clouds seen during Cassini's first flyby of Titan in July 2004, only now covering a larger area.

Titan's atmosphere, like that of Earth, is mostly nitrogen. The pressure at Titan's surface is 50 percent higher than on Earth, despite its lower gravity, meaning that the mass of the atmosphere per unit area is more than ten times that on Earth.

The image was taken in visible light with the Cassini spacecraft narrow angle camera on Sept. 23, 2004, at a distance of 7.1 million kilometers (4.4 million miles) from Titan and at a Sun-Titan-spacecraft, or phase, angle of 84 degrees. The image scale is 42 kilometers (26 miles) per pixel.

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 Cassini-Huygens 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 team is based at the Space Science Institute, Boulder, Colo.

For more information, about the Cassini-Huygens mission visit, http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://ciclops.org.