The Five Points of Lagrange

by Neil deGrasse Tyson

From Natural History Magazine, April 2002


The second and third Lagrangian points (L2 and L3) also lie on the Earth-Moon line, but this time L2 lies far beyond the far side of the Moon, while L3 lies far beyond Earth in the opposite direction. Once again, the three forces—Earth's gravity, the Moon's gravity, and the centrifugal force of the rotating system—cancel in concert. And once again, an object placed in either spot can orbit the Earth-Moon center of gravity with the same monthly period as the Moon.

 http://www.haydenplanetarium.org/tyson/read/2002/04/01/the-five-points-of-lagrange/


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