Nautical mile latitude could be used as the basis for a unit of measurement for distance and proposed the nautical mile as one minute or one-sixtieth () of one degree of latitude. As one degree is of a circle, one minute of arc is of a circle (or, in radians, ). These sexagesimal (base 60) units originated in Babylonian astronomy. Gunter used Snell's circumference to define a nautical mile as 6,080 feet, the length of one minute of arc at 48 degrees latitude. Since the earth is not a perfect sphere but is an oblate spheroid with slightly flattened poles, a minute
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