Fr.: équateur céleste
An imaginary great circle on the sky half-way between the → celestial poles. It is the projection of the → equator of the Earth on the sky.
true celestial equator
hamugâr-e âsmâni-ye râstin
Fr.: équateur céleste vrai
The → celestial equator of date, which is the → great circle on the → celestial sphere perpendicular to the instantaneous axis of rotation of the Earth. Its interaction with the → ecliptic defines the → vernal equinox of date and the → autumnal equinox of date.