Dione's lit hemisphere faces away from Cassini's camera, yet the moon's darkened surface features are dimly illuminated in this image, due to Saturnshine.
Although direct sunlight provides the best illumination for imaging, light reflected off of Saturn can do the job as well. In this image, Dione (698 miles or 1,123 kilometers across) is above Saturn's day side, and the moon's night side is faintly illuminated by sunlight reflected off the planet's disk.
This view looks toward the Saturn-facing side of Dione. North on Dione is up and rotated 8 degrees to the right. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Oct. 23, 2016.
The view was obtained at a distance of approximately 313,000 miles (504,000 kilometers) from Dione. Image scale is 1.8 miles (3 kilometers) per pixel.
The Cassini mission is a cooperative project of NASA, ESA (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. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colorado.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini. The Cassini imaging team homepage is at http://ciclops.org.