General 1

Navigation basics. We presume that the earth is a perfect sphere and is the center of the universe.
The earth is rotating round a hypothetical axis N and S and is penetrated in two points.
The upper point “N”, is called the North Pole and the lower point “S”, is called the South Pole.
“N” and “S” are known as the Geographical poles.
“C” is the center of the earth known as the core
Any plane passing through the center “C” is known as a Great Circle Plane.
The circumference of the great circle that is right angled to the hypothetical axis “N and S ” is called the Equator,
This divides the globe or sphere into two equal hemispheres, the northern hemisphere where the North Pole is located,
and the southern hemisphere where the South Pole is located.
The circumference of the small circle “A A1” with a plane parallel to the Equator, is called the Parallel of Latitude.