Equator of a planet
(gcide) | Equator \E*qua"tor\, n. [L. aequator one who equalizes: cf. F.
['e]quateur equator. See Equate.]
1. (Geog.) The imaginary great circle on the earth's surface,
everywhere equally distant from the two poles, and
dividing the earth's surface into two hemispheres.
[1913 Webster]
2. (Astron.) The great circle of the celestial sphere,
coincident with the plane of the earth's equator; -- so
called because when the sun is in it, the days and nights
are of equal length; hence called also the equinoctial,
and on maps, globes, etc., the equinoctial line.
[1913 Webster]
Equator of the sun or Equator of a planet (Astron.), the
great circle whose plane passes through through the center
of the body, and is perpendicular to its axis of
revolution.
Magnetic equator. See Aclinic.
[1913 Webster] |