zenith distance

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.

Word History and Origins

Origin of zenith distance¹

First recorded in 1695–1705

Example Sentences

This figured out the size of the earth with a percentage of error surprisingly small when we consider the rough means with which Eratosthenes measured the sun's zenith distance and the distance between the two stations.

From Project Gutenberg

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 Project Gutenberg

Form used in the computation of the zenith distance and azimuth of the moon.

From Project Gutenberg

A case is noted in the Indian survey where the zenith distance of a station 10.5 miles off varied from a depression of 4′ 52″.6 at 4.30 P.M. to an elevation of 2′ 24″.0 at 10.50 P.M.

From Project Gutenberg

To take an example: the mean of eight observations of the zenith distance of the sea horizon at the top of Ben Nevis is 91� 4′ 48″, or δ = 64.8; the ray is pretty equally disposed over land and water, and hence h = 1.047n�

From Project Gutenberg