This conditional line divides the Earth's surface intotwo hemispheres: Northern and Southern. It also serves to start the latitude reference in geography. What is the Equator? Imagine a plane perpendicular to the axis of rotation of the Earth and passing through the center. There? where this plane will intersect with the surface, and there is an imaginary equator.
Its length is more than forty thousand kilometers. The equator has the shape of a circle (since our planet is as if flattened from the poles and represents a geoid). Its radius, respectively, is equal to the radius of the Earth. Today's science allows us to determine the parameters of the equator with an accuracy of several meters.
The equator plays an important role in the coordinate system,long accepted for the convenience of movement and calculation of the way in cartography, geography and other sciences. In it, the meridians (two opposite, for example), like the equator, conditionally divide the globe in half. Parallels, as it were, slice the sphere with lobules, parallel to each other and to the equator and perpendicular to the meridians. Equator here is the origin of parallels. In general, the whole planet is divided into conventional rectangular figures, allowing you to accurately determine the location, according to latitude and longitude. For more information, see What is a coordinate system.