Bruce Murray Space Image Library

The "dark side" of Saturn

The "dark side" of Saturn
The "dark side" of Saturn This approximate true color view of the night side of Saturn was captured by Cassini on 19 May 2007. It shows how Saturn's night side is brightly illuminated by reflected light from Saturn's rings. NASA / JPL-Caltech / SSI / Gordan Ugarkovic

Sunlight is incident on the south (bottom) side of the rings, so the strongest illumination from ringshine is on the southern hemisphere of Saturn. The reflection goes to a minimum near the equator, where the effective area of the rings goes to zero (because they are so thin). There is also weaker ringshine lightening the northern hemisphere night side because the rings are partially transparent; light there has been scattered through the rings and bounces northward to Saturn. At the extreme left of the image daylight is illuminating Saturn's globe, and the rings casting shadows onto its blue northern hemisphere. Three moons are visible in this view: clockwise from the top, they are Enceladus, Epimetheus, and Mimas.