Oh - and do you have a link to your Electrodynamic spin gravity theory, Zarkov? @Janus58: are you saying that ALL satellites with a retrograde orbit are slowly approaching their primaries? (That would also include Phoebe, the outermost satellite of Saturn). If the reason is the motion of the tidal bulges those satellites cause on the said primaries, it must be infinitesimally small with most of them: I don't think Adrastea or Metis, for example, can generate any appreciable tides in the liquid mantle of Jupiter! The contrast in heating between the day and night sides of a planet would have more effect on its rotation than the tidal effect of such minor satellites.