hour circle
noun Astronomy.
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.
Nearby words
hounslow, houphouet-boigny, houppelande, hour, hour angle, hour circle, hour hand, hourglass, hourglass contraction, hourglass murmur, hourglass stomach
Origin of hour circle
First recorded in 1665–75
Also called circle of declination.
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British Dictionary definitions for hour circle
hour circle
noun
a great circle on the celestial sphere passing through the celestial poles and a specified point, such as a star
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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Science definitions for hour circle
hour circle
A great circle passing through the poles of the celestial sphere and intersecting the celestial equator at right angles. An hour circle is equivalent to a meridian on Earth and is used in describing the position of a celestial body with respect to an observer's celestial meridian. See more at hour angle.
The American Heritage® Science Dictionary
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