hour circle


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hour circle

n.
A great circle passing through the poles of the celestial sphere and intersecting the celestial equator at right angles.

hour circle

n
(Astronomy) a great circle on the celestial sphere passing through the celestial poles and a specified point, such as a star

hour′ cir`cle


n.
a great circle on the celestial sphere passing through the celestial poles and containing a point on the celestial sphere, as a star or the vernal equinox.
[1665–75]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.hour circle - a great circle on the celestial sphere that passes through both celestial poles
great circle - a circular line on the surface of a sphere formed by intersecting it with a plane passing through the center
References in periodicals archive ?
Meanwhile, the champagne-colored tapestry gold dial at 3 o'clock, the hour circle in mother-of-pearl, and black painted Roman numerals only add to the model's handsome aesthetic.
To complete this illusion, the metal borders of the discs were hidden in the hour circle.
The time of day is displayed in an off-centre dial that features a 1 to 31 scale for the date indicator within the hour circle.