zenith distance

American  

noun

Astronomy.

1. the angular distance from the zenith of a point on the celestial sphere to the sphere, measured along a great circle that is perpendicular to the horizon; the complement of the altitude.

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Etymology

Origin of zenith distance

First recorded in 1695–1705

Example Sentences

It is a little more accurate to find the altitude by taking the complement of the observed zenith distance, if the vertical arc has sufficient range.

From Scientific American Supplement, No. 360, November 25, 1882 by Various

Then the zenith distance is the distance from your zenith to the center of the sun.

From Lectures in Navigation by Draper, Ernest Gallaudet

Now if BC is the true meridian altitude of the sun at noon, 90�-BC or AB is your zenith distance.

From Lectures in Navigation by Draper, Ernest Gallaudet

Bradley had a zenith sector, and with this he observed with the greatest care the zenith distance of Gamma Draconis at every possible opportunity.

From Astronomy: The Science of the Heavenly Bodies by Todd, David Peck

Your zenith distance is the distance in the celestial sphere you are from the sun.

From Lectures in Navigation by Draper, Ernest Gallaudet