Answer:
Nutation
Step-by-step explanation:
The counterclockwise rotation of planet earth around its own axis is defined as the Earth Rotation. The earth rotates about the line called "the axis of rotation," it is an imaginary line that passes through the North and South Poles of the planet, which the earth rotates about.
Hence, earth rotates once in about 24 hours with respect to the Sun, from West to East and thus giving rise to;
a. Day and night
b. Seasons
The Earth motion which describes the wobbling of the Earth around its precessional axis and could alter the amount of seasonal effects is known as nutation.
Basically, nutation usually occurs when the precessional motion of a planetary body such as planet earth experience some form of irregularities when it is rotating.