Gyroscopes have always
fascinated me. Even after taking engineer physics classes and learning the principles, I still find it amazing
that the momentum of a spinning, stationary object will resist an attitudinal perturbance. This video demonstrates
the ability of a gyro to hold up a relatively heavy mass, and the resulting precession. It is the same phenomenon
that causes the Earth's 26k-year cycle of the
precession of the equinoxes.
Also demonstrated is nutation, which is the same kind of wobble that occurs with our moon that causes a slight
variation in the lines between the light and dark sides. It has the period of a lunar orbit. The Earth also
experiences nutation, but its period of 18.6 years is barely noticeable.