B and C in UV

RingsInUVOn 1 July, 2004, the Cassini spacecraft arrived at Saturn, marking the end of the spacecraft’s nearly seven-year journey through the solar system and the beginning of its tour of Saturn and the planet’s rings and moons.

This picture was taken in ultraviolet on 30 June, 2004 during Cassini’s orbital insertion maneuver. It shows, from left to right, the outer portion of the C ring and inner portion of the B ring which begins a little more than halfway across the image. The “dirty” particles are indicated by red, and “cleaner: ice particles shown in turquoise.

Saturn’s ring system is labeled from the inside out with the D, C, B and A rings followed by the F, G and E rings.

Image Credit: NASA

Rings and Shadows

ring shadowsjpgSaturn’s rings cast shadows on the planet, but the shadows appear to be inside out! The edge of Saturn’s outermost A ring can be seen at the top left corner of this picture taken by the Cassini spacecraft.  Moving down the image, one can see the faint Cassini Division, the opaque B ring, and the innermost C ring. The C ring contains several ringlets which appear dark against Saturn..  The bottom half of the picture shows the shadows of the rings in reverse order on the surface of the planet: the C ring, the B ring, the Cassini Division, and the inner half of the A ring.

Image Credit: NASA

New Moon?

new_moonThe Cassini spacecraft has documented the formation of a small icy object within the rings of Saturn that might be a new moon. It may also provide clues about the formation of some of the planet’s known moons.

Images taken with Cassini‘s narrow angle camera show disturbances at the very edge of Saturn’s A ring, the outermost of the planet’s large, bright rings. One of the disturbances is an arc about 1,200 km long and 10 km wide that is roughly 20 percent brighter than the surrounding ring.

The object is not expected to grow any larger, and may even be falling apart, but the process of its formation and outward movement in the ring aids in our understanding of how Saturn’s icy moons, including the cloud-wrapped Titan and ocean-holding Enceladus, may have formed in more massive rings long ago. It also provides insight into how Earth and other planets in our solar system may have formed and migrated away from the Sun.

Image Credit: NASA

Encountering Hyperion

This movie is a record of the Cassini spacecraft’s first close brush with Hyperion, a chaotically tumbling moon of Saturn. The jagged outlines are indicators of large impacts chipping away at Hyperion’s shape as a sculptor does to marble. The moon is too small to have pulled itself round by its own gravity. Its unusual dimensions are 328 by 260 by 214 km.

Video Credit: NASA