New model of precession, valid in time interval 400 thousand years
Precession is the secular and long-periodic component of the motion of the Earth’s spin axis in the celestial reference frame, approximately exhibiting a motion of about per year around the pole of the ecliptic. The presently adopted precession model, IAU2006, approximates this motion by polynomial expansions of time that are valid, with very high accuracy, in the immediate vicinity (a few centuries) of the reference epoch J2000.0. For more distant epochs, this approximation however quickly deviates...