Empeda
True, one of Saturn's moons is in a retrograde orbit, Phoebe.
It is also the farthest out orbit, but not very elliptical.
Quoted from this page,
http://nineplanets.org/phobos.html
"Open Issues
It seems likely that Phobos and Deimos formed elsewhere and were subsequently captured by Mars. But how did the capture occur? Was it made possible by a thicker Martian atmosphere long ago?"
Both Phobos and Deimos are not elliptical in their orbits. And I think they are grasping at straws about a thicker atmosphere, but then again maybe not. For a look at Deimos go here,
http://nineplanets.org/deimos.html
While doing some research on these "captured objects" Gale (FieryIce) and I came across this page describing Trojans of Jupiter.
http://www.ifa.hawaii.edu/~sheppard/sat ... rojan.html
We had never heard of them till today.
Astronomy is indeed a fascinating learning experience.
Norval
"It's not what you know, or don't know, but what you know that isn't so that will hurt you." Will Rodgers 1938