HST Captures a View of Four of Saturn’s Many Moons
So, last entry I had you examining the details of an image of a galaxy pair some 70 or so million light-years away. Today, we’re going to look at at the details of an HST image of a scene that played out some 70 or so light-minutes away at the planet Saturn.
If you click on the smaller image, you’ll get a much bigger one that shows the details of a rare transit of four of Saturn’s moons: Titan (the large one at the top of the limb of Saturn), Mimas (below Titan and casting a shadow near the rings) and bright Dione and fainter Enceladus off to the left. These transits only happen from our point of view when Saturn’s ring plane is nearly edge-on as seen from Earth.
Later this year, on August 10 and September 4, 2009, the ring plane will appear perfectly edge-on; however, we won’t be able to see that rarity because Saturn will be too close to the Sun for good viewing. These happen periodically though — in another 14-15 years we’ll get another chance to see the rings edge-on again.
Gaze at this image (particularly the large one) for a while — note the faint banding in Saturn’s atmosphere and the sharp shadow of Saturn’s rings darkening the cloud tops. For more information on the image and how the HST folks got it, check out the web site news release. It’s got details about the exposures used, the observation times and much more.
There’s even a nifty video sequence of four “eclipses” as the moons transit the planet. You can see it here.
And, thanks to Andy Chaikin for pointing out that there’s an even COOLER pic of the transits on the Hubble Heritage site. Those moons are lined up quite nicely!