Latitude constant latitude and constant longitude, which are constructed with reference to the rotation axis of the Earth. The primary reference points are the poles where the axis of rotation of the Earth intersects the reference surface. Planes which contain the rotation axis intersect the surface at the meridians; and the angle between any one meridian plane and that through Greenwich (the Prime Meridian) defines the longitude: meridians are lines of constant longitude. The plane through the centre of the Earth and perpendicular to the rotation axis intersects the surface at a great circle called the Equator. Planes parallel to the
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