As I mentioned in a recent blog post, Saturn is currently presenting itself to us with its rings and moon orbits nearly edge-on. I knew this would mean we'd see transits of the moons: from our view, the moons seem to pass directly over the face of Saturn.
What I didn't think of is this also means the moons will cast shadows on the rings themselves! This is starting to happen now, and Cassini, our robot-on-the-spot, is now sending back spectacular pictures (like it ever sends back any other kind, duh) of these events! The animation you see here (click to embiggen) shows the tiny moon Epimetheus -- only 113 km (70 miles) across -- casting its own shadow on the rings. While it was still a million kilometers from the tiny world, Cassini took a series of images that the ground team strung together into this beautiful and somewhat ...
