As a comparison, here is a shot I took a few nights ago (22Dec)
of a similar field with an 80mm refractor and DSLR.
I have noted the times when the exposures were saved on HD.
These are 3 x 30 sec exposures , separated by 10 sec intervals and show
similar movement rate of a satellite. I'm not saying at all it is the same sat,
only an example of a typical drift rate.
A low orbit polar type sat would move much faster than this so my
guess would be a similar one to Jason's.....a satellite further out
(but not as far out as geostationarys- these move much slower and I have
photographed them) and probably in it's closest phase of an elliptical
orbit....
BTW, great shot! Look forward to seeing some more!
Steve