EQUATOR (

See also:

• LATE

Late

See also:

• LAT

Lat. aequator, from aequare, to make equal)  , in geography, that great circle of the earth, equidistant from the two poles, which divides the northern from the southern hemisphere and lies in a plane perpendicular to the axis of the earth; this is termed the " geographical " or " terrestrial equator." In astronomy, the " celestial equator " is the name given to the great circle in which the plane of the terrestrial equator intersects the celestial sphere; it is consequently equidistant from the celestial poles . The " magnetic equator " is an imaginary line encircling the earth, along which the vertical component of the earth's magnetic force is zero; it nearly coincides with the terrestrial equator .