Ecliptic
Glossary · Last updated: 2026-07-26
The ecliptic is the great circle on the sky traced by the Sun over a year. The Moon and planets stay close to this path, which is why zodiac signs lie along it.
Tropical zodiac zero starts at the March equinox point on the ecliptic. Sidereal zodiac zero anchors to fixed stars with ayanamsa.
Obliquity
Earth's tilt (obliquity) creates seasons and defines the equinoxes that anchor tropical signs. Precession slowly shifts those equinox points against the stars.