One of the rewards of being an amateur astronomer is that from time to time you get to discover on your own astronomical facts that were actually discovered centuries ago. Like the orbital period of Titan. About ten days ago I reported on my early morning observations of Saturn. Titan was in the far right of my field of view. Then, a week later I looked again and saw that Titan was now in the far left of the field of view. It looked like it it had gone to the opposite end of its orbital track in about a week. I checked and, sure enough, Titan takes about 15 earth days to complete an orbit. Neat. 
(Photo from NASA, text from New Scientist)A study in contrasts, this photo captures three illuminated moons as a darkened Saturn looms in the shadows. Only the planet's rings are visible but its shape can be traced from the way it partially obscures its rings and one of its moons.
The large foreground moon is Rhea at 1528 kilometres across. Nearly a third of Rhea's size, sunny Enceladus is on the right. Dione, at 1123 kilometres wide, rounds out the trio to the left with a night-cloaked Saturn obstructing part of it.
The photo was taken by NASA's Cassini spacecraft in April. Cassini has been exploring Saturn's 62 known moons since it reached the ringed planet in 2004.
There is a big and very unusual storm on Saturn right now. You can see it in the image above. It was taken by amateur astronomer Jim Phillips using an eight inch telescope. I've been out before dawn for the last two mornings trying to see the storm with my 6 inch Dobsonian reflector telescope. I get very nice views of Saturn and Titan, but I can't quite make out the storm. Conditions have not been great, and I'm not sure the storm was in view when I was looking.
After a long spell of looking almost exclusively at Jupiter and our Moon, I was very pleased to see that Saturn is now visible. It is up in the south-east just before dawn, to the upper right of VERY bright Venus. The Sky and Telescope screen shot is a good representation of what I saw. I was using a 6 inch reflector telescope. I could see Titan very easily, and I could also see Rhea by using the averted vision trick.
Above is a much better view of Rhea. This one was taken by the Cassini spacecraft last November. Rhea has been in the news recently because scientists have discovered oxygen in its atmosphere: 
Now for some real DX. The Cassini probe is exploring the moons of Saturn. Above you see a picture of the planet in eclipse -- the sun is behind it. Click on the picture to make it larger. Look closely between the rings at around the ten o'clock position. That's us. That's Earth.
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