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
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.