
NASA / JPL-Caltech / SSI
Two of Saturn's more than 60 moons join the ringed planet in this scene, captured by the Cassini orbiter on Jan. 19 and released on April 30. Tethys appears as a small white dot above the rings on the far left of the image. Enceladus appears as a smaller bright speck beside the planet. The rings cast wide shadows on the planet's southern latitudes.
Two of Saturn's moons are dwarfed by the giant planet and its rings in this family portrait from the Cassini spacecraft, which will mark its eighth year in Saturnian orbit in July. This image was put out by the Cassini imaging team on Monday, just a little too late to make our Top 20 roundup for the Month in Space Pictures — but it's worth passing along as a bonus prize.
You can see 660-mile-wide Tethys as a white dot toward the left edge of the image, and 313-mile-wide Enceladus as a smaller bright speck beside the planet. Tethys is thought to be composed mostly of water ice with a bit of rock mixed in, while Enceladus is a very special case: Cassini has repeatedly documented geysers of water ice spewing from fissures in that moon's surface — suggesting that liquid water and perhaps even living things may lie beneath. It'll be up to a future probe to plumb the mysteries of Enceladus more deeply.
Saturn's rings are seen nearly edge-on, and in this picture they're casting wide, curved shadows on Saturn's southern hemisphere. Bad Astronomy's Phil Plait says he can't help noticing the thin white ribbon of clouds stretching across the planet's northern hemisphere. Those may be the remnants of a monster storm that wrapped itself around the globe for months, starting in late 2010. "Our gas giants don't screw around," he writes. "When they do something, they do it big."
And when we do the Month in Space Pictures slideshow, we do it big as well. Click on the image below to see some of the best out-of-this-world views from the month of April. You'll find shots from the final flights of the shuttles Discovery and Enterprise, photos of weird phenomena on Mars and Uranus, and even a UFO (Galaxy, that is). If you want to find out more about the stories behind the pictures, leave a comment and I'll try to point you in the right direction.
Alan Boyle is msnbc.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter or adding Cosmic Log's Google+ page to your circle. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for other worlds.



Fantastic images! ;-)
Cassini has been one terrific return on the joint investment (between NASA and the ESA; for it's Titan landing probe, Huygens). We've learned so much about the outer solar system in the last few decades. I still remember being in middle school when the first Voyager images came back from Jupiter and Saturn.
Nice that this generation can experience some of that awe as well....
Both of those moons have water on them. Wow, life out there may be closer than we think!
It'd be amazing if life were discovered somewhere else in our own solar system, wouldn't it? Even if only in primordial forms. It'd instantly double the chances for life all over the universe..
I absolutely love this stuff. Incredibly gorgeous pictures. Thanks for sharing, Alan!
WOW! Great pictures. I will visit this place again tonight before I fall asleep.
I have always been fascinated with Saturn ever since I saw it through a 7" refractor telescope at Brooklyn College back in the early 1970's. Its own self contained solar system, it is just a beautiful planet. Of course, back then Saturn had 'only' 9 moons, and we did not know about the 'shepherd moons' within the rings. Our knowledge of our solar system has sky rocketed over the past 40+ years. The work Spirit and Odyssey on Mars is just phenomenal.
@ Mr. Boyle, you keep publishing these wonderful articles, and I will keep enjoying them. THANK YOU
What a great slide show Alan ....
Seemed like about 5 or 6 sets ....
I just kept pressing forward getting more and more sets ....
Nice job again Alan Boyle ....