I enthused about these Helene images the first time they came down from Cassini, and then forgot about them, and then was thrilled anew a couple of weeks ago when Daniel Macháček posted his version, processed from data published by the Cassini imaging team on April 1.
In the last few days as it's rounded periapsis in its current orbit of Saturn, Cassini has taken a lot of great photos of Saturn's moons. One series of photos was taken from pretty close to Janus, a moon about a third the diameter of Enceladus that orbits between the F and G rings. And among those, several were taken with the moon sitting in front of Saturn.
Since Cassini currently orbits Saturn within the plane of Saturn's rings, it has lots of chances to catch two or more moons in the same photo. One such "mutual event" happened on September 17, featuring four moons: Titan, Dione, Pan, and Pandora.
I'm preparing a talk for the Pacific Astronomy and Telescope Show here in Pasadena on Sunday afternoon at 1:45. I have spent the morning putting together a slide that I have long wanted to have for presentations.
Yesterday Cassini passed unusually close by Hyperion, the oddly shaped moon that orbits Saturn just beyond Titan. Among the many cool images captured during this flyby were three that I used to make this neato view of Hyperion's crescent.
A few weeks ago a producer for a public television space documentary asked me if I knew of any cool Cassini animations and my answer was, "Ooh, what a great excuse to have some fun digging around in the Cassini data archives." Here is the most fun animation I came up with in response to the request.
Cassini has finally achieved gorgeous global imaging of Helene with a spectacular flyby on Saturday, in which they 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!!
Last week I got very excited about a set of pictures that had appeared on Cassini's raw images website, but was sad that I couldn't make color versions myself. I was so excited that I failed to identify the little icy moon in the picture correctly.
I've got some lovely pictures from Saturn to show you! Every three months, the Cassini mission dumps gigabytes worth of precious Saturn data into the Planetary Data System, and the latest gift came on April 1. This particular pile of data, which was taken between April 1 and June 30, 2010, contains a lot of really terrific moon observations.
Regular readers of this blog will find the content of today's 365 Days of Astronomy Podcast familiar, because it's an update on what the solar system exploration spacecraft are up to, based on my monthly "what's up" updates.
Daniel Macháček has reached into the dark side of Prometheus and pulled out an incredible amount of detail where the potato-shaped moon is illuminated by Saturnshine. He produced an animation that morphs among the three sets of four-filter color images that Cassini snapped during the flyby.