CICLOPS: Cassini Imaging Central Laboratory for OPerationS
Captain's Log
April 23, 2012


A Most Beguiling Ring

Today the Cassini Imaging Team presents to you a glimpse of what patience, care and painstaking analysis can bring. And it is glorious.

Recall the F ring of Saturn ... a solitary ring of icy debris, lying outside Saturn's main rings, that first came into view during the historic Voyager flybys of Saturn in the early 1980s. Voyager found a bright ring, shepherded into a tight orbital corridor by two of Saturn's moons, Prometheus and Pandora, the so-called 'shepherd moons.' The dynamical influence of these moons explained for the most part the F ring's narrowness.

But it was the complexity of this ring that baffled: isolated bright clumps, individual strands, braided regions, kinky segments all seemed at the time to be inexplicable. It was strongly suspected, however, that the ring's special location plays a major role: ie, it lies at a distance from Saturn where the planet's shearing tidal forces, still present here but weakening, are offered stiff competition by the coalescence-encouraging gravitational attraction among ring particles.

Fast forward 22 years, Cassini arrives at Saturn, and finds more of the same. But this time, it's different: now we imaging scientists have the luxury of observing the behavior of this ring closely for extended periods of time ... a gift resulting from the finely tuned orbital trajectory of the spacecraft that brings us at times sufficiently close to Saturn and the F ring to make detailed observations.

And that we've done. Tens of thousands of Cassini images later, we have come finally to understand the intricate workings of this most beguiling ring. We have learned that there is a heirarchy of gravitational influences at work in this strange beast, beginning with the channels and jets and small, loosely aggregated bodies that are created when Prometheus, whose orbit, like the F ring's, is eccentric, comes close to the ring. Some of these bodies soon get destroyed by collisions with other bodies or by the tidal forces from Saturn which eagerly rip them apart. But some are strong enough and survive long enough to plow their own way through the F ring, creating the fine, irregular structure and smaller jets that have now been found through careful inspection of images of the F ring taken over the past 8 years.

And so, we continue our Saturnian explorations knowing, with a certain satisfaction and pleasure, that one of our solar system's finest mysteries has yielded finally to our scrutiny.

Next, our voyage takes us out of the equatorial plane and up and over the rings, where we will enjoy repeated and prolonged looks at the intricate structures therein, and the polar regions of the planet. With nothing in our way, it's full speed ahead.


Carolyn Porco
Cassini Imaging Team Leader
CICLOPS
Space Science Institute
Boulder, CO
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Alliance Member Comments
sunwell (Jun 10, 2012 at 7:46 AM):
It is time for the universe of meaningless.Maybe it's secret is all around us.exploration never sleep.
sunwell (Jun 3, 2012 at 3:48 AM):
Life is not the result of the most valuable it is a process.
thespis2717 (May 15, 2012 at 0:17 AM):
I must say that the Cassini images of Saturn's total solar eclipse are some of the most beautiful spectacles I've ever seen. It is truly awe-inspiring, and the team who looks over these missions deserves a standing ovation that lasts so long they become annoyed with the sound of applause. Tremendous work!
GorT> (May 11, 2012 at 9:54 AM):
Carolyn, I'm deeply enamored by ring geology...It can't just be all ice and dust. There has to be some remnants of precious metals in there. Maybe a form of fuel, if we ever travel out to Sextor six...Maybe you could pilot Cassini through the ring...I'm sure you'de probably have to change your orbit, to more of a North-South heading...
GorT> (May 11, 2012 at 9:53 AM):
Carolyn, I'm deeply enamored by ring geology...It can't just be all ice and dust. There has to be some remnants of precious metals in there. Maybe a form of fuel, if we ever travel out to Sextor six...Maybe you could pilot Cassini through the ring...I'm sure you'de probably have to change your orbit, to more of a North-South heading...
GorT> (May 11, 2012 at 9:52 AM):
Carolyn, I'm deeply enamored by ring geology...It can't just be all ice and dust. There has to be some remnants of precious metals in there. Maybe a form of fuel, if we ever travel out to Sextor six...Maybe you could pilot Cassini through the ring...I'm sure you'de probably have to change your orbit, to more of a North-South heading...
sunspot51 (May 7, 2012 at 6:28 PM):
Can someone give me an idea of the approx ratio of ice to non-ice in Saturn's rings. An overall estimate would do. Or maybe point me to a solid source of that information.

Thanks!!
Paul Maxson
sunspot51@cox.net
Larrythebassman (May 3, 2012 at 2:14 AM):
WOW_Jupiter's_RINGS_the New Horizon.
WOW_thank you _so much
sunwell (Apr 29, 2012 at 7:15 PM):
The rest of us really are suckers.
sunwell (Apr 27, 2012 at 8:54 AM):
More and more.
GorT> (Apr 26, 2012 at 11:13 PM):
F ring...I mean G string...!
rochelimit (Apr 24, 2012 at 10:39 AM):
Amazing amazing amazing amazing amazing!
NeKto (Apr 24, 2012 at 8:02 AM):
our faithful robotic friend out there in orbit around Saturn, and the talented crew who direct it, have teamed up to give us another spectacular set of images.
Great Job Team!
thanks again.