In this week's Science,
a team of researchers using the Cassini spacecraft report discovering the elusive source of Saturn's G ring. Until now scientists were stumped when it came to finding an explanation for why the G ring was where it was. Now it seems that the G ring is likely produced by icy debris blocks found in a bright arc along the ring's inner edge. The arc's material is influenced by the moon Mimas's gravity.
To learn more, check out the team's press release. And be sure to see some of the cool images and videos of the region.