[TimesDomain]

The difference between simulation and reality?

Let's see - you can have Olive Oil (Popeye's girlfriend) as your prefered simulations ....

.... and I'll have Raquel or Gina Lollobrigida.

THAT is the difference.

[Lonesome in Massachussets]

I'm sure the orbital elements of Uranus' major moons are known with far more than the necessary accuracy to have predicted this. (They recently accurately predicted the occlusion of a star by one of Neptune's moons, iirc, a much, much harder feat.)

I think that the guys studying Neptune's atmosphere just didn't do the calculations and were pleasantly surprised. BTW, moons' shadows on Jupiter are observed and photographed all the time.