Latitude and Longitude


Latitude and Longitude are spherical coordinates on the surface of the earth. Latitude is measured North or South of the Equator, resulting in a range of -90 (S pole) to +90 (N pole) degrees. Longitude is measured East or West of Greenwich, and can be expressed in different ways. For example, 120 degrees West Longitude is also 240 degrees East Longitude, since the earth is round, and 360 degrees make a circle. The choice of sign for longitude is also somewhat arbitrary. Some uses require (+) for West, others use (+) for East. Winorbit can use any of these formats, as well as expressing the angles in decimal degrees (such 40.077 deg N) or degrees, minutes and seconds (40 deg 04 min 37 sec).

Note that while a degree of latitude or longitude is about the same at the equator (60 nautical miles), this is not true as one approaches the poles, where a degree of longitude eventually becomes infiinitesimally small.