This is a rather interesting article, Helene turns out to have some strange geological formations.
http://www.planetary.org/blog/article/00003072/#c5t_formThe Cassini team has had a wretched time trying to get pictures of Helene in the past, but their streak of bad luck is over. Helene is one of the four "co-orbital" moons in the Saturn system, which occupy metastable spots in the leading and trailing Lagrangian points on the orbits of Tethys and Dione. It's the biggest of the four, but that's not saying much; it's only about 36 by 32 by 30 kilometers across, so it's in the same general size range as Phobos. It's proven challenging to predict where it's going to be with enough accuracy to make sure Cassini can capture it in its camera field of view, with the result that nearly every imaging sequence that Cassini has been commanded to take of Helene has seen the moon wander out of the field of view at one time or another.
Well, Cassini has finally achieved gorgeous global imaging of Helene with a spectacular flyby on Saturday, in which they absolutely nailed the spacecraft's pointing and got Helene to pose prettily for the camera from beginning to end of the encounter. And what a wacky, wacky world Cassini has revealed Helene to be!!