Saturn's moon Helene, seen here with Saturn's nearly edge-on rings, orbits
60 degrees ahead of Dione and is called a "Trojan" moon. The tiny moon
Polydeuces (about 5 kilometers or 3 miles across, recently discovered by
Cassini imaging scientists) is also a Dione Trojan, orbiting 60 degrees
behind. Helene is 32 kilometers (20 miles) across.
The image was taken in visible light with the Cassini spacecraft
narrow-angle camera on March 12, 2005, at a distance of approximately 2
million kilometers (1.2 million miles) from Helene and at a
Sun-Helene-spacecraft, or phase, angle of 90 degrees. Resolution in the
original image was 10 kilometers (7 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 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.