There are several really, really big craters on various parts of Iapetus, but none of them really suggest an obvious association with the dark stuff.
It's so tempting to propose some association with the equatorial ridge, but what that association would be is not clear. The ridge seems to peter out somewhere in the western transition region after poking up those white mountains, and it doesn't really go all the way to the eastern end. But it's mostly in the dark area.
2007-09-15 09:07 pm (UTC)
2007-09-16 01:24 am (UTC)
at least thats what the patterns the dark spots all over the right side suggest.
not sure if theres a crater on the far side to match the ejecta spray.
2007-09-16 03:22 am (UTC)
It's so tempting to propose some association with the equatorial ridge, but what that association would be is not clear. The ridge seems to peter out somewhere in the western transition region after poking up those white mountains, and it doesn't really go all the way to the eastern end. But it's mostly in the dark area.
(Anonymous)
2007-09-16 11:33 am (UTC)
I want to see the spectra...
Andreas Morlok