Have a pretty Saturn picture
Jul. 8th, 2010 08:46 am![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
mmcirvinDaphnis making ripples in the Keeler Gap. (Color picture, made from slightly different frames, here.)
The moon orbits from upper left to lower right in the picture, inside the gap. Its feeble but persistent gravity clears ring particles out of the interior of the gap. Daphnis's orbit isn't exactly coplanar with the rings, so it effectively bobs up and down and its gravity raises complicated ripples in the edges. The ring particles on the outer side of the gap (lower left) are moving more slowly than Daphnis, so the ripples trail behind it. The ring particles on the inner side are moving faster, so the ripples lead the moon on that side. Ripples like these, raised in various ways by moons and moonlets, gradually get stretched out by the differential motion of the particles, and wrapped around the rings to form regular wave structures like the ones visible in the rest of the picture.
The moon orbits from upper left to lower right in the picture, inside the gap. Its feeble but persistent gravity clears ring particles out of the interior of the gap. Daphnis's orbit isn't exactly coplanar with the rings, so it effectively bobs up and down and its gravity raises complicated ripples in the edges. The ring particles on the outer side of the gap (lower left) are moving more slowly than Daphnis, so the ripples trail behind it. The ring particles on the inner side are moving faster, so the ripples lead the moon on that side. Ripples like these, raised in various ways by moons and moonlets, gradually get stretched out by the differential motion of the particles, and wrapped around the rings to form regular wave structures like the ones visible in the rest of the picture.