Recent observations of Saturn’s rings from Cassini reveal some vertical structure to the rings. Shown here are disturbances caused by Daphnis, a small moonlet that orbits within the Keeler Gap of the rings. We have seen much of these kinds of disturbances in the rings from tiny moonlets, but the Saturninan equinox finally provides us with an angle of sunlight that reveals such structures from the long shadows they cast. The tallest shadow seen at right is Daphnis itself.
Some recent posts from Gordan Ugarkovic. The first is just gorgeous, the second featuring Prometheus and Pan in the gaps, the third is also just real pretty and the 4th is two sides of Enceladus. The 2nd and 4th of these images are false color which we publish less often, but these were just too nice to deny.
Yes, another movie of Prometheus disturbing Saturn’s rings. This is the longest clip and includes the most ring swinging action for your money. This version has been cropped and reduced down from the original. See here for a larger, wider view of the same animation (2M gif).
From the raw images of the Cassini mission. This is Saturn’s tiny moon Prometheus causing a disturbance in some ring particles. Nothing really new to be said here as we have seen this featured in a few animations posted here before. This is just a nice image of that phenomenon with the addition of a nice glaringly over-exposed Prometheus.
Looking at the 500 most recent raw images from Cassini, one of the pages was filled with nothing but images of the rings at various angles and locations. The tiling of these images on one page was unintentionally interesting and I thought we would repeat a more intentional version here with those same images.
This image taken on January 18, 2008 from 988,018 km, reminds one of some of those vintage Voyager images of Saturn (seen at left) from back in the early and mid 1980’s. Just compare at the incredible differences between the quality and color of the Voyager vs. Cassini images. Saturn images during the Voyager era were all consistently yellow and brown, but today’s Cassini images reveal Saturn to be a rich peach color mixed with hints of yellow and brown. We also have the advantage of being witness to the rich blues currently appearing in the northern hemisphere which did not exist in 1981 or 1986.
The one Saturn image that we keep coming back to at wanderingspace seems to be the Ian Regan portrait of Saturn. The composition, angle and color captured in the shot somehow seem to be better than any other. While there are a few other full Saturn images now available from the Cassini mission, none seem to have captured the drama that this one does. The angle that the ring shadows fall on Saturn’s disc, the phase that Saturn happened to be in at the time and the color available as the shot was taken from a more northern position. However, trying to apply the image to larger scale resolutions was not possible as the resolution in the orignal would require that the rings be extended to fill the frame on the left, right, bottom and potentially the top as well (I was also curious to see if the image was just as impressive if it was not angled and cropped as it is in the original). Extending the rings in one direction is easy enough, but doing it on all sides is near impossible to try to do in any image editing software such as Photoshop.
Instead, a one pixel wide swash of the rings was sampled and turned into vectors using Adobe Illustrator. This further allows Illustrator to stretch and curve the ring information captured without having to worry about resolution or pixel distortion. The row of rings was then applied to a brush pattern and applied and wrapped to a simple circle shape. Now the rings are in full circle and the proportions are adjusted. That full set of rings was then rendered in 3-D software and the correct angle as well as perspective was applied and matched with the original Ian Regan image underneath the render for reference.
After that, all that is left to do is merge the Regan image to the rings (and maintain as much of the original image as possible) and artificially add the disc shadow that would fall upon the rings behind the planet iteself.
There have been some nice NASA animations of the interaction between some “shepard” moons and the rings, but this has to be the most impressive. There are some blank frames in there for gaps in the data… but the effect is still easy to follow.
Among the various worlds in our celestial neighborhood, Saturn stands apart as a most photogenic. With the help of a complex system of rings it naturally lends itself to more scenic images as compared to the more detail oriented images we see from such other places such as Mars or Jupiter. The “Saturn Scenes” set (downloadable here as a zipped file) was compiled from some of the best scenic images from the Cassini mission that had the potential to fill a 2560x1600 frame.
In order to completely fill that frame out some rendering and sampling has been applied to the original images. These additions are briefly noted in the images themselves and are as noted here…
DIONE AND SATURN features the moon Dione passing in front of the edge of Saturn’s disc. The original image would only fill about 1/4 of the frame so some of the details have been sampled and expanded to fill out that full frame’s proportions. The details of the rings are sampled from this image and based upon other photographic references. The left 2/3 of the rings seen here were rendered and are not actual. The lower 1/5 of Saturn’s disc was sampled and extended from the original image. Lastly, the top darkest ring shadows were rendered based upon a fair amount of actual data that was actually present in the original but was cropped short.
SATURN (which is named “SATURN-2.jpg” in the file name) has had a considerable amount of rendering to extend the details of the rings to fill out this larger 2560x1600 frame. The original color composite work was masterfully performed by Ian Regan for unmannedspaceflight.com and has become a wanderingspace favorite. In order to extend the rings to fill out the frame as accurately as possible, a one pixel wide sampling of the full set of rings was captured and digitally translated to vectors. These vectors were then stretched and applied to a circle path which was then rendered in 3-D software to achieve the correct perspective of the original. Once a match was made, the new vector based rings were then blended into the actual original image and some masking was applied to represent Saturn’s shadow falling upon the rings. Despite the heavily rendered nature of the rings, virtually no part of the disc of Saturn itself has been altered and is 99.5% original and actual.
All other images are actual and unaltered.
NASA released an unusually large amount of color images to the Cassini website recently. Most of what is shown here on this site are actually images put together by freelance imagers who access the raw files and do some stitching together of filtered images. Color images coming straight off the Cassini website are a rare event, so when about 8 appeared in the gallery a few days ago… it was an unexpected gift. Saturn as seen from the unlit side of the rings.
A family portrait of the Saturn System. Moons visible in this image (you need to click the preview) are Dione at far left, Enceladus near the left side ring edge, Mimas a speck on ring shadows on the western limb, Rhea against the northern hemisphere, Tethys near the right ring edge, and Titan near lower right.
Hopefully by now, most people are aware of the shocking activity at this small moon named Enceladus at Saturn. It appears the moon is continually spewing out material (likely water-ice and rock) from a number of geysers located around its southern pole (see Life in the Hood: Enceladus for reference).
This image was taken around September of 2006, and reveals how Enceladus is actually constructing another ring around Saturn. The “ring” is not normally very visible, but by taking the image with the sun almost directly behind the structure - the particles become back-lit and appear brighter, like dust in a ray of light.
Close inspection of the image reveals quite a bit going on in there. You can see a darker path behind Enceladus as it sweeps up materials already left in it’s path from previous orbits. While in front and around the small moon, you can see jets of material being generated and going into orbit around Saturn. A similar phenomenon is happening at Jupiter with the torus created by Io’s volcanos as well, but I am unaware of any images illustrating that phenomenon as detailed as the one seen here.