The Cassini spacecraft has imaged the dumpling/walnut/ravioli-shaped Pan, a shepherd moon in Saturn's Encke Gap with a mean radius of around 14.1 km:
Even as it nears a sad end in September, the Cassini spacecraft is continuing to delight as it makes some of its final orbits through the Saturn system. As part of these "ring-grazing" maneuvers, the spacecraft has just returned the best-ever images of the small, walnut-shaped moon Pan. [...] In earlier research, [Carolyn] Porco and other planetary scientists have suggested that Pan, as well as Daphnis and some of the other small moons in the Saturn system, were once denser cores that had about one-third to one-half their present size.
Also at NASA JPL, Science Magazine and The Verge.
(Score: 5, Informative) by c0lo on Friday March 10 2017, @12:15AM (1 child)
> Compared to the gap in the rings that it creates, I expected it to be a lot smaller.
Its mean density [wikipedia.org] (0.42±0.15 g/cm³) would allow it to float on water; less than half of it submerged - approximately the same density as aspen or willow wood.
The escape velocity from its surface is 6 m/s - the average human can reach 6.7 m/s for short speed runs. Essentially, it's a pile of un-compacted dust - not enough gravity to pull itself into a spheroidal shape.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by bob_super on Friday March 10 2017, @12:53AM
It's actually convenient, a probe thrown at it to figure out what size rock started it would easily pierce through.
Those rings never cease to amaze me.