Twice-lit Janus

Janus, Saturn's small moon named after the two-faced god, here displays two illuminated hemispheres.Janus (179 kilometers, 111 miles across) orbits beyond the thin F ring in the top left of the image. The moon is lit by sunlight on the left and light reflected off Saturn on the right.This image, taken a little more than a week after Saturn's August 2009 equinox, also shows vertical structures in