hughhyatt wrote:Also, why is the inner edge of the inner ring that's in Saturn's shadow offset from the one that's not in shadow? Surely, we're not seeing more through light that's reflected off the rings, then off the planet and finally back through the rings than we're seeing through scattered direct sunlight. BTW, the same thing appears to be true of the outermost edge that's in Saturn's shadow as well.
The backside of Saturn is illuminated by:
1) back scattered sunlight off the sunlit side of the rings and
2) side scattered sunlight off the night side of the rings.
Neither ring illumination gets to Saturn's poles which don't see the rings.
Neither ring illumination gets to Saturn's equator hardly sees the rings.
However, the ring illumination does gradually gets brighter as one moves away from the Saturn's equator into the temperate zones
particularly in the Southern Hemisphere which receives ring back scattered sunlight.
The "inner edge of the inner ring that's in Saturn's shadow " is
actually the surface of Saturn itself demonstrating the contrast between the poorly lit Northern Hemisphere and the well lit Southern Hemisphere. The two dark bands on Saturn's Southern Hemisphere are simply the thick B & A ring bands preventing us from a relatively clear view of Saturn's entire back side. These thick B & A ring bands are also dark in the space view because they are truly (multiply scattered) opaque bands. The fact that the bright non-opaque C & D bands in the space view are approximately as bright as Saturn's back lit Southern Hemisphere (as seen through the C & D bands) is simply coincidence and the two (space & Saturn views) should not be confused with each other.
