Starship Asterisk*

Prometheus and the F Ring

Explanation: In Greek myth Prometheus was a Titan, known for bringing fire from Mount Olympus. But in modern times the name is given to is a small moon of Saturn, orbiting just inside Saturn's F ring. In a complex interaction, the tiny potato-shaped moon interacts with the icy ring particles creating structures along the F ring still not fully understood. One of the highest resolution views of Prometheus, this image of its pocked surface posing with the thin F ring in the background was taken during the Cassini spacecraft's close approach on December 6, 2015. Prometheus is about 86 kilometers (50 miles) across.

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Awesome....

Um....looks like the potato I had the other day....

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Boomer12k wrote:
Um....looks like the potato I had the other day....

''Why do you doubt your senses?''

''Because,'' said Scrooge, ''you may be an undigested bit of beef, a blot of mustard, a crumb of cheese, a fragment of an underdone potato.''

The orbital resonances of Saturn’s moons are fascinating. The orbital dance of Epimetheus and Janus, like Prometheus and Pandora’s interaction with the F-ring, will keep our curiosities perked for years to come.

It appears that this photo may answer the question of the origin of streaks on Phobos. If you magnify the crater in the center of the image, the boulder responsible for a streak to the right appears to be resting to the left on the lower right lip of the crater. The shadow cast by the boulder is light to dark instead of the dark to light of the craters indicating that it is prominent from the surface rather than indented.

The relevant Phobos image with commentary on "strange streaks" was posted January 24, 2011 on APOD at http://apod.nasa.gov/apod/ap110124.html.

LRing wrote:It appears that this photo may answer the question of the origin of streaks on Phobos. If you magnify the crater in the center of the image, the boulder responsible for a streak to the right appears to be resting to the left on the lower right lip of the crater. The shadow cast by the boulder is light to dark instead of the dark to light of the craters indicating that it is prominent from the surface rather than indented.

The relevant Phobos image with commentary on "strange streaks" was posted January 24, 2011 on APOD at http://apod.nasa.gov/apod/ap110124.html.

I don't think the resolution of this image is sufficient to reliably come to that conclusion about what we're seeing. And even if your analysis is correct, it tells us little about processes on Phobos. There are two accepted theories about the streaks on Phobos, both reasonable and both still requiring additional testing: that they are essentially crater chains produced by material ejected from the Martian surface by impacts, or that they are faulting caused by tidal deformation.

This is a beautiful beautiful imagen