Circle of latitude can be calculated by a common sine or cosine function. The 60th parallel north or south is half as long as the Equator (disregarding Earth's minor flattening by 0.3%). A circle of latitude is perpendicular to all meridians. The latitude of the circle is approximately the angle between the Equator and the circle, with the angle's vertex at Earth's centre. The equator is at 0°, and the North Pole and South Pole are at 90° north and 90° south, respectively. The Equator is the longest circle of latitude and is the only circle of latitude which also is a great
The Longest Voyage The Longest Voyage "The Longest Voyage" is a science fiction short story by American writer Poul Anderson. It won the Hugo Award for Best Short Story in 1961. On a distant world the age of exploration is beginning. A party of daring explorers attempts to circumnavigate their world. In unknown waters they encounter an island civilization which claims to have a prophet who fell from the stars. "The Longest Voyage" won the 1961 Hugo Award for Best Short Story. Gardner Dozois, upon selecting "The Longest Voyage" for inclusion in his 2000 anthology "Explorers: SF Adventures to Far Horizons", said that