Saturn’s “Strange” Ringlet
While the IAU has decided on a definition of “planet”, that body of astronomers might want to consider the almost embarrassing lack of names for Saturn’s many rings. Within the main ring system of Saturn are many small, distinct ringlets. A few of them, like the Huygens ringlet, have names. In this recent Cassini image of the Huygens ringlet (inside the Huygens Gap, of course), you can see another narrow ringlet that I happen to have a particular grudge against. This narrow fellow, nicknamed the “strange ringlet” by some in the Cassini Rings Working Group, appears not to go all the way around Saturn. While it looks perfectly ordinary in the image above, in my observations of stellar occultations by the rings, this ringlet appears sometimes, but not all the time. Some images also seem to show the ringlet disappearing. This is pretty unusual behavior for planetary rings, and might be a clue to the existence of a new moon embedded within the rings. I got excited last year that our data might show that it is an inclined, eccentric ringlet, passing over the main rings at some points in its orbit. But this idea is too simple to explain all the observations. It may be inclined and eccentric, but it has some additional wrinkles that we will have to figure out. Maybe by then we’ll also have a proper name for it.