Epimetheus and the Rings

November 27, 2013

Download Full Image

While the moon Epimetheus passes by, beyond the edge of Saturn's main rings, the tiny moon Daphnis carries on its orbit within the Keeler gap of the A ring. Although quite different in size, both moons create waves in the rings thanks to their gravitational influences.

Epimetheus (70 miles, or 113 kilometers across) is visible at the lower-right of the image, and Daphnis (5 miles, or 8 kilometers across) is barely visible at one pixel wide just below-right of the image center. A close inspection of the image also reveals the waves Daphnis creates on the edges of the Keeler gap.

This view looks toward the unilluminated side of the rings from about 2.6 degrees below the ringplane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on June 28, 2013.

The view was acquired at a distance of approximately 808,000 miles (1.3 million kilometers) from Daphnis and at a Sun-Daphnis-spacecraft, or phase, angle of 28 degrees. Image scale is 5 miles (8 kilometers) per pixel.

Image credit: NASA/JPL-Caltech/Space Science Institute