# What is nutation in relation to earth?

Nov 19, 2016

See explanation

#### Explanation:

The cyclic precession-nutation motion of the polar axis of the Earth

is similar to the motion of thf the spinning toy, Top.

Precession is motion along the surface of a double right circular

cone, with vertex near the center of the Earth. The period of this

revolution is called Great Year = 258 centuries, nearly. The semi-

angle of this cone is about ${23.4}^{o}$.

Tn this interactive play of mutual attractions of the triad the Earth,

the Sun and the Earth's orbiter Luna, there is lateral oscillations

(nodding) of either Pole called Nutation, on the surface of the Earth,

about its Great Year circular path.. This nutation comprises quite a

number of oscillations with different periods.

For graphic depiction see wikipedia.org/wiki/Nutation