In an appropriate reference frame it can be defined as a change in the first Euler angle, whereas the third Euler angle defines the rotation itself.- Precession
The fixed-axis hypothesis excludes the possibility of an axis changing its orientation and cannot describe such phenomena as wobbling or precession.- Rotation around a fixed axis
2 related topics
Nutation is a rocking, swaying, or nodding motion in the axis of rotation of a largely axially symmetric object, such as a gyroscope, planet, or bullet in flight, or as an intended behaviour of a mechanism.
However, in spacecraft dynamics, precession (a change in the first Euler angle) is sometimes referred to as nutation.
Rotation is the circular movement of an object around an axis of rotation.
Another consequence of the rotation of a planet is the phenomenon of precession.