Astrolabe Glossary and Notes

Ecliptic

The apparent annual path of the sun against the backdrop of the fixed stars. This great circle is inclined 23°27’ degrees from the celestial equator and intersects it at the vernal and autumnal equinoxes, i.e., on 20 March when the sun enters the zodiacal sign of Aries and on 22 September when the sun enters the zodiacal sign of Libra.
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