August 6, 2016
orbit, ellipse, focus, ovoid, comet, S2, star, planet, Mercury, perihelion precession, Newton, Kepler, Relativity, theory, measures, demonstration
Since Kepler and Newton, orbits are known to be perfect ellipses. An ellipse is characterized by its eccentricity lower than 1, two focus and a periodicity. But it can remain trouble in the explanation of some celestial bodies’ motions: the motions of few comets with an eccentricity slightly higher than 1 are expected to be periodic. And for the orbital ellipse, there is a lack of ‘physical meaning’ for the second focus. Introducing the Lorentz factor, it is demonstrated here that the orbit would not be an ellipse with a double focus, but a flat ovoid with a single focus. This figure could be used for comets, for stars as S2 in the centre of our Galaxy, and for planets. And in particular the perihelion precession of Mercury around a single focus is more understandable. An accurate comparison of the demonstrations of the Theory of Relativity and of the Neo-Newtonian Mechanics is given in Appendix. At low speed, the ovoid looks like an ellipse. So ellipse orbit appears to be a simplified case of the general ovoid orbit.