A circle of a sphere is a circle defined as the intersection of a sphere and a plane. If the plane contains the center of the sphere then the circle is called a great circle, otherwise it is a small circle. Circles of a sphere have radius less than or equal to the radius sphere, with equality when the circle is a great circle.
In the geographic coordinate system on a globe, the parallels of latitude are such circles, with the Equator the only great circle. By contrast, all meridians of longitude, paired with their opposite meridian in the other hemisphere, form great circles.
The diameter of the sphere which passes though the center of the circle is called its axis and the endpoints of this diameter are called its poles. A circle of a sphere can also be defined as the set of points at a given angular distance from a given pole.
Read more about Circle Of A Sphere: Geometric Proof
Famous quotes containing the words circle of, circle and/or sphere:
“Every few years something new breaks into the circle of my thoughts.”
—Mason Cooley (b. 1927)
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—Mason Cooley (b. 1927)
“One concept corrupts and confuses the others. I am not speaking of the Evil whose limited sphere is ethics; I am speaking of the infinite.”
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