Sphère armillaire
A geometric model for celestial coordinates and motions.
Aperçu
The armillary sphere models the celestial sphere as nested rings representing great circles such as the equator and the ecliptic. From ancient China and Greece through the Islamic world and Renaissance Europe it served as a coordinate-measuring instrument and a teaching model of the heavens.
Découvertes clés
- Enabled measurement of equatorial and ecliptic coordinates
- Demonstrated celestial-sphere models in classical astronomy
- Antecedent of later graduated positional instruments