One of the topics I found most exciting yesterday was a series of talks on Titan's climate. Bob West showed how Titan's detached haze has shifted with time. Zibi Turtle presented about how Titan's weather has changed with these seasonal changes. Jason Barnes followed up Zibi's talk -- which was based on Cassini camera images -- with a study of the same regions using data from Cassini's imaging spectrometer, trying to figure out what was going on with that brightening. Ralph Lorenz talked about rainfall rates on Titan. Jeff Moore asked: what if Titan hasn't always had a thick atmosphere?
Clearly, this is Saturn, and its rings, and if you look closer you can see a tiny circle, on top of the rings, which is Mimas, and two stars in the background. It should look weird to you that while the rings are bright, Mimas is a black dot. What is happening here? Nearly everything in this picture is lit by light that has not arrived directly from the Sun.
When I posted about the really cool Cassini SAR images of Enceladus a few weeks ago, I initially wrote that this was the first-ever SAR image of an icy moon other than Titan. Several people (some readers and two members of the Cassini science team!) corrected that statement: Cassini has performed SAR imaging of other icy moons (including Enceladus) before.
On the November 6, 2011 flyby of Enceladus -- the third such flyby in just a few weeks -- the Cassini mission elected to take a SAR swath instead of using the optical instruments for once. So here it is: the first-ever SAR swath on Enceladus. In fact, the only other places we've ever done SAR imaging are Earth, the Moon, Venus, Iapetus, and Titan.
It's been a week of very heavy science on this blog, so I thought it'd be nice to go into the weekend with a post in which a breathtaking picture speaks for itself, without needing my thousands of words.
It's been a very full day at the DPS-EPSC 2011 joint meeting. My day was less full than it might have been, because I overslept and missed most of the morning's session. I really needed the rest though so I think it was probably for the best!
Today they turned on the scientific fire hose at the Division of Planetary Sciences / European Planetary Science Congress meeting happening here in Nantes, France. My brain already feels full and I still have four more days!
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.
About four years ago I wrote a blog entry about an ESA press release about paper published in Nature that suggested that Saturn's moons Tethys and Dione might have volcanic activity, like Enceladus. A new paper published in Icarus casts doubt on that conclusion.
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.
I haven't checked in on Cassini lately. I went to the raw images page and found the frames for this very lovely, very close view of Saturn. It was taken by Cassini two days ago, as it was approaching periapsis.