CICLOPS: Cassini Imaging Central Laboratory for OPerationS
The Great Crossing

The Great Crossing
PIA 08356

Avg Rating: 9.10/10

Movie 980x900:
Flash 1.9 MB
MP4 movie 2.7 MB


The Great Crossing
PIA 08356

Avg Rating: 7.65/10

Still Image 980x900:
PNG 215 KB
  This life-like movie sequence captures Saturn's rings during a ringplane crossing -- which Cassini makes twice per orbit -- from the spacecraft's point of view. The movie begins with a view of the sunlit side of the rings. As the spacecraft speeds from south to north, the rings appear to tilt downward and collapse to a thin plane, and then open again to reveal the unilluminated side of the ringplane, where sunlight filters through only dimly.

The striking contrast between the sunlit and unlit sides of the ringplane can now be fully appreciated, thanks to the sense of continuity in time and space provided by this brief clip.

The movie consists of 34 images taken over the course of 12 hours as Cassini pierced the ringplane. Additional frames were inserted between the original images in order to smooth the motion in the sequence -- a scheme called interpolation.

Six moons careen through the field of view during the sequence. The first large one is Enceladus, whose slanted motion from upper left to center right nicely illustrates the inclination of its orbit with respect to the rings. The second large one, seen in the second half of the movie, is Mimas, going from right to left.

This movie begins with a view looking toward the lit side of the rings from about 9 degrees below the ringplane. It ends when the spacecraft is 8 degrees above the ringplane.

The clear filter images in this movie sequence were taken with the Cassini spacecraft wide-angle camera on Jan. 17, 2007 at a distance of approximately 900,000 kilometers (500,000 miles) from Saturn. Image scale is 48 kilometers (30 miles) per pixel.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA's Science Mission Directorate, Washington, D.C. The imaging team consists of scientists from the US, England, France, and Germany. The imaging operations center and team lead (Dr. C. Porco) are based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini-Huygens mission, visit and the Cassini imaging team home page,

Credit: NASA/JPL/Space Science Institute
Released: April 2, 2009 (PIA 08356)
Image/Caption Information

Alliance Member Comments
zacharyj67 (Jan 4, 2008 at 3:50 PM):
This is a stunning sequence! However, I believe I counted seven moons, not six . . . three on the bright side of the rings (one very small body moving from right to left in the lower left side of the image and at the very beginning of the sequence and two moving from left to right above the rings) and four after the inversion to the dark side of the rings (three small bodies moving from left to right below the rings and one large body moving from right to left above the rings). Is it posasible one of them is not a moon? I would appreciate being corrected if I am wrong.

I am so grateful to be able to see this . . . it is beautiful beyond description!!
Moonsister (Mar 15, 2007 at 7:54 PM):
Every time I watch this movie, I hear/feel the breeze as we cross the rings. An antique Pink Floyd album called 'Meddle' has a song that begins with the breeze I hear, tho the song's words don't quite fit..("one of these days I'm going to cut you into little pieces")..Perhaps a Satriani song 'Big Bad Moon' might be better heard with this one, after the Pink Floyd breeze sound intro..hmmmmmmm
Moonsister (Mar 15, 2007 at 2:06 AM):
When I first saw this movie and the stills on Video File I was speechless...I recorded them and have played them back for friends and family, all had the same reaction--stunned silence! Awe! To know we live in the same solar system as this majestic and utterly alien world wets one's appetite for more! MORE! MORE! A standing ovation is in order, and an Oscar!!
Iapetus Monolith (Mar 6, 2007 at 5:36 PM):
Stupendous! (Do Alliance Members who can identify all the moons get bonus points?)
richard (Mar 4, 2007 at 6:28 PM):
this is great, better than my telescope
Ramses (Mar 4, 2007 at 7:53 AM):
This is just outstanding
My jaw is open looking at this!
Big fan of this site and visit daily!
carolyn (CICLOPS) (Mar 1, 2007 at 8:16 PM):
Moonbird (great name, by the way) ... Cassini's nominal mission ends the middle of 2008. However, chances are excellent that we will be given an extension of two more years, and we are currently planning for that. We should know with certainty really soon. After that, I would say it's likely we will be given further extensions, but it's hard to predict the funding level that far ahead. Fingers crossed for us. And be sure to let your congresspeople know that you feel Cassini is a worthy use of your taxpayer dollars.
moonbird (Mar 1, 2007 at 6:05 PM):
What really impresses me here is the motion of the moons both the larger ones and the smaller on the outer most ring. These "movie" sequences really help me perceive the Saturn system as the dynamic place it must be (made the hair on my neck tickle as I watched the first time)-- thanks so much for the incredible glimpse of that ... helps to break down my perception of it as a distant cold giant.

BTW -- what is Cassini's expected lifespan? I could look at these images for a long, long time -- I am proud to have contributed (as a lowly taxpayer) to such a noble venture!!
RobCass (Mar 1, 2007 at 11:07 AM):
Superb movie of the rings !
I hope in the near future Cassini will expose some ring spokes and this would be taken into an even more exciting animation (as the legendary Voyager spoke movies).