Great Year

The Great Year is the long cycle of time measured not in years, but in the slow turning of the heavens.

Caused by the precession of Earth's axis, this cycle spans approximately 25,920 years, during which the position of the equinox gradually shifts through the constellations. Though refined by modern astronomy to approximately 25,770 years, the concept of this vast cosmic rhythm has been observed, interpreted, and transmitted across civilizations for millennia.

This book traces the development of the Great Year from its earliest observational foundations in Mesopotamia, through Greek and Roman thought, and across the cosmological systems of India, Mesoamerica, and China. It examines how ancient cultures recorded long term celestial change, how these observations were preserved and transformed, and how they were ultimately explained through the physics of Newton and refined by modern scientific measurement.

Bringing together history, astronomy, and philosophy, The Great Year presents a disciplined and evidence based account of one of the most profound cycles in nature.

It is not a work of speculation, but of continuity.

From ancient observation to modern science, the turning of the axis remains one of the clearest expressions of time on a cosmic scale.