How does precession affect earth?

1 Answer
Dec 16, 2016

Not in a big way but there is some effect. See explanation


The precession period is the Great Year = 258 centuries, nearly..The

poles complete one rotation in this period, about a mean position,

upon the surface of the Earth. Correspondingly, either ( no-shadow-

noon ) equinoxes rotate along the equator. This backward angular

speed is #(360/25800)^o=0.014^o#/year. The time equivalent for

this retrograde movement is

(24X3600)/25800 sec/year = 3.35"/year = 5.7 minutes/century..

So, there is an effect but not in a big way.

Importantly, the orbit of the Earth about the Sun and the year is mot

affected by precession of equnoxes. In other words, the instants for

perihelion and aphelion are not shifted because of this precession

of either the equinox (or, for that matter, precession of either solstice )..