Misleading Perspective

Dione and Rhea together near the rings
October 24, 2005
PIA NumberPIA07614
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The Saturn moon Mimas is much smaller than Rhea, but the geometry of this scene exaggerates the actual differences in size. Here, Mimas is on the opposite side of the rings from Rhea and Cassini. Mimas' diameter is 397 kilometers (247 miles), while Rhea's diameter is 1,528 kilometers (949 miles).

Saturn's shadow slices across the ringplane here. The view looks toward the Saturn-facing hemisphere on Mimas, and the anti-Saturn hemisphere on Rhea.

The image was taken in visible light with the narrow-angle camera on Sept. 9, 2005, from a distance of approximately 1.5 million kilometers (900,000 miles) from Rhea. Mimas was located on the far side of the rings, about 670,000 kilometers (420,000 miles) farther from Cassini. The image scale is 9 kilometers (6 miles) per pixel on Rhea and 13 kilometers (8 miles) per pixel on Mimas.

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 operations center is based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov . The Cassini imaging team homepage is at http://ciclops.org .

Credit: NASA/JPL/Space Science Institute