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Eddington limit




The theoretical limit at which the radiation pressure of a light-emitting body would exceed the body's gravitational attraction. A star emitting radiation at greater than the Eddington limit would break up. This would happen, for example, to a star of more than about 120 solar masses, or to the Sun if its luminosity were increased by a factor of 30,000. The Eddington limit, named after Arthur Eddington, is given by

L = 4πGMmpc / σT

where G is the gravitational pressure, M is the mass of the luminous object, mp is the mass of a proton, c is the speed of light, and σT is the effective area of an electron when it is illuminated by radiation.


Related category

   • STELLAR ASTROPHYSICS