Discovery · c. 130 BCE

Precession of the Equinoxes

History of Astronomy

Overview

Hipparchus discovered that the equinox points slowly drift along the zodiac, completing a circuit in about 26,000 years, by comparing his star positions with older records.

Why it matters

The first detection of a long-term motion of the Earth's axis, and a landmark in precise positional astronomy.

Credit

Discovered by

Hipparchus

Knowledge connections

Discovered byHipparchus
Part ofGreek Astronomy
Associated withThe Ecliptic & Equinox
Associated withPrecession

Sources & references

Facts on this topic will be cited from these primary and reference sources.

BritannicaEncyclopaedia Britannica
General reference for the history of astronomy, biographies, and cultural context.

Loading…