Equatorial
[,ekwə'tɔːrɪəl] or [,ɛkwə'tɔrɪəl]
Definition
(noun.) a telescope whose mounting has only two axes of motion, one parallel to the Earth's axis and the other one at right angles to it.
(adj.) of or existing at or near the geographic equator; 'equatorial Africa' .
(adj.) of or relating to conditions at the geographical equator; 'equatorial heat' .
(adj.) of or relating to or at an equator; 'equatorial diameter' .
Checker: Rudolph--From WordNet
Definition
(a.) Of or pertaining to the equator; as, equatorial climates; also, pertaining to an equatorial instrument.
(n.) An instrument consisting of a telescope so mounted as to have two axes of motion at right angles to each other, one of them parallel to the axis of the earth, and each carrying a graduated circle, the one for measuring declination, and the other right ascension, or the hour angle, so that the telescope may be directed, even in the daytime, to any star or other object whose right ascension and declination are known. The motion in right ascension is sometimes communicated by clockwork, so as to keep the object constantly in the field of the telescope. Called also an equatorial telescope.
Checker: Lorrie
Examples
- On the lofty mountains of equatorial America a host of peculiar species belonging to European genera occur. Charles Darwin. On the Origin of Species by Means of Natural Selection.
- Watson has remarked, in receding from polar toward equatorial latitudes, the Alpine or mountain flora really become less and less Arctic. Charles Darwin. On the Origin of Species by Means of Natural Selection.
- In this way the polar diameter, or diameter from pole to pole, is shorter than the diameter at right angles to this--the equatorial diameter. Various. The Wonder Book of Knowledge.
- The Grand Equatorial of Gruenewald, at the recent Berlin Exposition, was even still larger, since its object glass was 3 feet 7 inches, or nearly 2 inches larger than the Yerkes. Edward W. Byrn. The Progress of Invention in the Nineteenth Century.
- He accordingly wrote to Professor Challis, July 9, requesting him to employ for the purpose the great Northumberland equatorial of the Cambridge Observatory. Walter Libby. An Introduction to the History of Science.
- The most accurate measurements make the polar diameter about twenty-seven miles less than the equatorial, the equatorial diameter being found to be 7,925. Various. The Wonder Book of Knowledge.
Typist: Malcolm