Cassini’s Take on Saturn’s Rings

Images by NASA's Cassini spacecraft reveal the wondrous Saturn system in fantastic detail. These observations have also provided fodder for detailed simulations of what's afoot in the rings. Below, you'll find images that didn't make it into our May 2013 cover story on Saturn's majestic Hula-Hoops, plus up-close looks (both real and animated) that follow how the rings change with time.

Enceladus jets

This image is a mosaic of two high-resolution images captured by Cassini’s narrow-angle camera when the spacecraft flew through Enceladus’s jets on November 21, 2009. These dramatic plumes spray water and organic compounds out from many locations along the famed "tiger stripes" near the south pole of the Saturnian moon. Cassini scientists continue to study the question of whether reservoirs of liquid water exist beneath the surface.
Credit: NASA / JPL / Space Science Institute

F ring wiggles

This mosaic covers a small section of Saturn’s F ring, with the vertical axis representing distance from Saturn and the horizontal axis representing longitude around Saturn (the images have been processed to make the ring follow a straight line instead of an arc). In addition to the powerful perturbing effect of the moon Prometheus, a population of small objects probably interacts with the ring's core to produce the structures seen. Click for a more complete view (shows 70% of the ring's circumference).
Credit: NASA / JPL / Space Science Institute

Green Saturn

Taken from Saturn’s shadow, this enhanced-color mosaic shows the planet and rings backlit by the Sun. The composite includes images taking through infrared, red, and violet spectral filters.
Credit: NASA / JPL / Space Science Institute

Saturn system

While on final approach for its September 2007 close encounter with the moon Iapetus, Cassini spun around to take in a sweeping view of the Saturn system. Titan appears in the lower right. In the zoom view (click the image for the large version), you can see (from left to right) Dione, Rhea, Tethys, and Titan.
Credit: NASA / JPL / Space Science Institute

The planet Venus appears as a white pinprick between Saturn's rings in this true-color image from Cassini.
Credit: NASA / JPL-Caltech / Space Science Institute

The moon Prometheus slowly collides with the diffuse inner edge of Saturn's F ring in this movie sequence of Cassini images. The oblong moon pulls a streamer of material from the ring and leaves behind a dark channel. Once during its 14.7-hour orbit of Saturn, Prometheus (102 kilometers, or 63 miles, across) reaches the point in its elliptical path called apoapse, where it is farthest away from Saturn and closest to the F ring. At this point, Prometheus' gravity is just strong enough to draw a "streamer" of material out of the core region of the F ring. Image sequence taken 23–24 November 2006.

A series of images from Cassini show how the B ring's dark spokes change with time.

Not real, but really cool, is an animation of the B ring, which shows the ring from above, with the radial direction running from left to right. The frame moves with the orbital motion of material at the frame's radial center; thus material radially inwards moves faster (ahead) and material radially outwards moves slower (behind); this is the so-called Keplerian shear. The particles range up to 5 m radius and have internal density of 0.5 g/cm3. Click to view.

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