Colure

Colure
From LoveToKnow 1911
COLURE (from Gr. KOXos, shortened, and ovpfi, tail), in astronomy, either of the two principal meridians of the celestial sphere, one of which passes through the poles and the two solstices, ...

colure: (archaic) a great circle on the celestial sphere that passes through the north and south celestial poles. See also equinoctial colure.

Colure A great circle that passes through the celestial poles and either the equinoxes (equinoctial colure) or solstices (solstitial colure) ...

equinoctial colure (NASA SP-7, 1965) That great circle of the celestial sphere through the celestial poles and equinoxes; the hour circle of the vernal equinox. equinoctial day (NASA SP-7, 1965) = sidereal day.

Theta, Beta (Menkalinan), Pi, and Delta Aurigae closely line up along the Solstitial Colure (the curved line immediately to the left of them), and thus point the way to the North Celestial Pole and Polaris.

(More about the ecliptic, equinoxes and solstices further on.) As an added bonus, other features may be present, such as the analemma, and-I had to look this one up-the equinoctial colure.

See also: Light, Earth, Distance, Orbit, Sky