What Is The Equator?

The imaginary
great circle around the earth's surface, equidistant from the poles and
perpendicular to the earth's axis of rotation. It divides the earth
into the Northern Hemisphere and the Southern Hemisphere.A similar great circle drawn on the surface of a celestial body at right angles to the axis of rotation.

The equator, in geography, is an imaginary line, which runs around the planet, exactly halfway between the north and south poles. The surface of the planet, along this equatorial line, is parallel to the axis of rotation.  The planet is divided into Northern and Southern Hemisphere, by the equator. The latitude here is 0°. The length or the distance around the Earth's equator is around 24,901.5 miles, or 40,075.0 km.

Both sunrise and sunsets are experienced at the quickest rate, in regions along the equator. These regions also experience days and nights that have a very constant duration, spanning twelve hours each throughout the year. The sun passes directly overhead at noon, with its rays being perpendicular to the earth's surface, on the days of equinox.

Equatorial regions have a wet climate throughout the year, but seasons can vary, according to the region's proximity to the ocean or factor's like elevation.

The equator is the line that goes through the centre of the earth

The Equator (from Wiki)

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