what do you mean by the last term?
The celestial equator is the great circle of the imaginary celestial sphere on the same plane as the equator of Earth.
Celestial equator
The celestial equator is the great circle of the imaginary celestial sphere on the same plane as the equator of Earth.
what type of path do planets follow around the sun orbit what is ecliptic? The ecliptic is the plane of Earth's orbit around the Sun. is there a celestial reference plane? The ecliptic forms one of the two fundamental planes used as reference for positions on the celestial sphere, the other being the celestial equator.
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Celestial equator [SEP] Introduction
The celestial equator is the great circle of the imaginary celestial sphere on the same plane as the equator of Earth. This plane of reference bases the equatorial coordinate system. In other words, the celestial equator is an abstract projection of the terrestrial equator into outer space. Due to Earth's axial tilt, the celestial equator is currently inclined by about 23.44° with respect to the ecliptic (the plane of Earth's orbit). The inclination has varied from about 22.0° to 24.5° over the past 5 million years. An observer standing on Earth's equator visualizes the celestial equator as a semicircle passing through the zenith, the point directly overhead.