I’ve frequently said the Cassini spacecraft is an artist, so when Carolyn Porco, the mission’s imaging team lead, mentioned on Twitter that Saturn’s moon Prometheus is akin to Michelangelo, I had to take a look. Wow, this gorgeous image is suitable for framing! Visible in the perturbed, thin F ring, is the potato-shaped Prometheus, and having performed the perturbing, it continues in its orbit. Click the image for the super-huge version.
Prometheus (148 kilometers, 92 miles across) periodically creates streamer-channels in the F ring, and the moon’s handiwork can be seen as the dark channels. Here’s a movie made from Cassini images showing this process:
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on June 1, 2010. A star is also visible through the rings near the center right of the image.
There are also some additional features in the F ring, courtesy of Prometheus.
This Cassini image shows icy particles in Saturn’s F ring clumping into giant snowballs as the moon Prometheus makes multiple swings by the ring. Scientists say that the gravitational pull of the moon sloshes ring material around, creating wake channels that trigger the formation of objects as large as 20 kilometers (12 miles) in diameter.
“Scientists have never seen objects actually form before,” said Carl Murray, a Cassini imaging team member based at Queen Mary, University of London. “We now have direct evidence of that process and the rowdy dance between the moons and bits of space debris.”
Read more about these fans and snowballs in this JPL article.