In the paper “The Gyro-Gravitational Spin Vector Torque Dynamics of Main Belt Asteroids in relationship with their Tilt and their Orbital Inclination” I found the excellent compliance between the observations and the extrapolations of E. Skogl?v and A. Erikson, 2002, and the theoretical deductions according the Maxwell Analogy for Gravitation. This implies namely the existence of the second gravitational field: Gyrotation (Co-gravitation). Six of the seven observations are directly explained by the theory. The seventh observation: “there is a significant majority of asteroids with a prograde spin vector compared to retrograde ones” is explainable by supposing that the asteroids are created, like most of the planets are, prograde. The theory found that the asteroids’ spins are expected to end-up as retrograde. Two factors play a role: the speed of change of tilt due to gyrotation, and the other influences like the perturbations by Jupiter and Saturn or the gravitational librations. Here, mainly the gyrotation part is studied analytically and graphically, and commented.
Keywords: Main Belt Asteroids, gravitation, gyrotation, prograde, retrograde, orbit, precession, nutation, tilt, angular momentum