This may be my favorite picture of Saturn's moon Enceladus yet:
Quick! It's trying to get away! My first thought (well, my real first thought was that this is Enceladus on full afterburners) was that this was a composite: two images combined. The moon is icy and very bright, while the plumes of water shooting away from cracks in its surface are faint. But actually, there are two separate light sources here! The face of the Moon we see here is being lit by a full Saturn (think of Saturn as being behind you as you look at the picture). But the Sun is behind Enceladus (not directly behind, but mostly behind and off to the side of the picture), and is illuminating the geysers. That's why the fainter plumes are visible; we're looking at the dark side of the moon! If Saturn weren't lighting it up, the moon would ...
