On Monday, October 30, 2017 at 4:53:49 PM UTC, palsing wrote:
Gerald wrote;

Most of these issues are new and barely touched.

All of these issues are well understood and have been for a very, very long time.

How I wish that were so. The foundations of timekeeping have been presented in its entirety including the orbital benchmark which defines the proportion of rotations to one orbital circuit, the proportion of rotations to four orbital circuits and the additional refinement of rotations per orbital circuits known through the precession of the equinoxes insofar as the same framework and observations works for more general to more detailed proportions of rotations to orbital circuits.

A good start is DST which demonstrates how the rotation of the Earth is anchored to noon.