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Target 2: F Ring

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Target 2: F Ring

Jonathon Smith

Cassini Navigator

Computer simulation of Target 2: F ring
Software used by the Cassini science planning team simulates the field of view the cameras on board the Cassini spacecraft can capture at a specific date and time. This is a computer-generated image of a portion of the rings that includes the F ring as should be as seen by the Cassini spacecraft's Narrow Angle Camera on Sept. 20, 2012.
+ Click on the image for a larger view

Hi, my name is Jonathon, and I'm a Navigator for the Cassini Spacecraft. Along with the rest of the navigation team, I help steer Cassini to interesting places in the Saturn System.

For this observation, I think that we should point Cassini to image Saturn's "F" ring, which is our Target number two.

From far away, it looks as if Saturn is surrounded by a single, giant ring. However, when you get up as close as Cassini is, you can see that there are really many different rings of varying sizes and compositions. Scientists have named these rings "A" through "G."

My favorite is the F ring, a very thin and faint ring discovered in 1979 by NASA's Pioneer 11 spacecraft.

The F ring is kept thin and narrow by two "shepherd" moons, Prometheus and Pandora. These moons orbit on either side of the F ring and keep it from diffusing into space. They are like two sheep dogs that keep their herd of sheep from wandering off.

One of these moons creates large snowballs as it plows through the F ring, and these snowballs puncture the ring as they tumble around Saturn. There are some estimates that five hundred of these snowballs are cutting in and out of the F ring's orbit, making it one of the most dynamic places in the Saturn system.

Every observation of the F ring tells us something new, and that's why I think you should choose Target two.