First of all the rotation axis ... wobble. Although it was already discovered by American astronomer Seth Carlo Chandler in 1891 the exact cause of this change of Earth’s spin with a period ...

Superimposed is a subtler wobble. The axis keeps steady in space, but over an uneven period of about one year, the bulk of the earth moves slightly in relation to the axis. Gold uses this motion ...

This event is commonly called the "African Humid Period (AHP ... and a 20,000-year cycle in the "wobble" — much like a top wobbles — of the Earth's axis (precession). All three of orbital ...

Earth is currently in an interglacial period, with the last glacial period ... or changes in Earth's axial tilt and how the axis wobbles around itself, respectively — play a part in the waxing ...