Latitude exact relationship of parallels and meridians with horizontal and vertical: both are complicated curves. On the sphere the normal passes through the centre and the latitude () is therefore equal to the angle subtended at the centre by the meridian arc from the equator to the point concerned. If the meridian distance is denoted by then where denotes the mean radius of the Earth. is equal to . No higher accuracy is appropriate for since higher-precision results necessitate an ellipsoid model. With this value for the meridian length of 1 degree of latitude on the sphere is (60.0 nautical miles).
The Equator monument The Equator monument The Equator monument is located on the equator in Pontianak, Indonesia. It marks the division between the northern and southern hemispheres. The monument consists of four iron wood poles, each with a diameter of about 0,30 metre, with frontage bollard height is two pieces as high as 3,05 radian place backside bollard and the signpost dart as high as 4,40 metres. Its location is in "Jalan Khatulistiwa", North Pontianak, about 3 kilometres from the city centre of Pontianak. The equator monument is not on the equator any more. The equator has moved slightly southwards and there is