celestial sphere(redirected from equatorial plane)
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An imaginary sphere of infinite extent with the earth at its center and on which the stars, planets, and other heavenly bodies appear to be located.
(Astronomy) an imaginary sphere of infinitely large radius enclosing the universe so that all celestial bodies appear to be projected onto its surface
the imaginary, infinite sphere formed by the sky, the center of which is a given observer's position.
An imaginary sphere with Earth at its center. The stars, planets, sun, moon, and other heavenly bodies appear to be located on this sphere.
An imaginary sphere of infinite radius concentric with the Earth, on which all celestial bodies except the Earth are imagined to be projected.
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|Noun||1.||celestial sphere - the apparent surface of the imaginary sphere on which celestial bodies appear to be projected|
apex of the sun's way, solar apex, apex - the point on the celestial sphere toward which the sun and solar system appear to be moving relative to the fixed stars
celestial point - a point in the heavens (on the celestial sphere)
nadir - the point below the observer that is directly opposite the zenith on the imaginary sphere against which celestial bodies appear to be projected
surface - the extended two-dimensional outer boundary of a three-dimensional object; "they skimmed over the surface of the water"; "a brush small enough to clean every dental surface"; "the sun has no distinct surface"
zenith - the point above the observer that is directly opposite the nadir on the imaginary sphere against which celestial bodies appear to be projected
zodiac - a belt-shaped region in the heavens on either side to the ecliptic; divided into 12 constellations or signs for astrological purposes