February 2, 2017
Agreed with this, there are various ideas in the literature whch are used to try to explain why solar system orbits appear to be two dimensional with respect to the sun. Most of them use evolutionary arguments. However, the sun is itself orbiting the centre of the Milky Way, so the overall orbits of the planets are three dimensional as you infer. It seems that the Milky Way (a spiral galaxy) is also orbiting another galaxy. The orbit of the moon about the earth is nearly circular, and tilted at 5 degrees to the earth’s orbit about the sun. So the moon’s orbit about the sun is not planar as you infer.”
So you and Sewage are beginning to realize that there really is no such thing as a 3-dimensional orbit. Like all pseudoscientists, you have to resort to ‘playing with semantics’. Yes, one can get all sorts of exotic results by playing games with the chosen coordinate system. But no scientist would call the resultant convoluted movements ‘orbits’; they would call them ‘paths’. It is, to a first degree of approximation, irrelevant what angle the Moon’s orbital plane has with respect to the ecliptic, because one need treat only the planar orbital motion of the centre-of-mass of the Earth-Moon system about the Sun. Incidentally, if one does take the trouble to determine the path [sic] of the Moon around the Sun one discovers quite an interesting fact. We did not previously believe that we could lure you into falling for an age-old misconception but, having seen you fall so heavily for the Old Wives’ Tale of the ‘levitating top’, we now think that it is worth a try. So here is the question which fooled the ‘genius’ Tesla, a Chief Inspector of Schools and many another opinionated sciolist. It is this: does the Moon rotate? It would be just too delightful if you got the answer wrong … and Warwick could add yet another of our points to the Wiki ECE page.