Relative Luminosity from relative size and temperature

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Equation / Last modified by KurtHeckman on 2019/08/16 00:18
`L = `
sspickle.Relative Luminosity from relative size and temperature

The Relative Luminosity from Relative Size and Temperature calculator computes the relative luminosity based on the relative size and the relative temperature.

INSTRUCTIONS: Enter the following:

  • (T) This is the Relative Temperature.  It is the absolute temperature divided by the temperature of the reference object.
  • (R)  This is the Relative Size.  It is the radius divided by the radius of the reference object.

Relative Luminosity: The calculator returns the relative luminosity (L)

The Math / Science

The formula for the relative luminosity of a star based on the relative temperature and size is:

     L = R2•T4


  • L = Relative luminosity 
  • R = Relative Size
  • T = Relative Temperature

For example, suppose you have a star with 10 times the radius of the Sun but half the absolute temperature. The luminosity of this star would be:

  L = 102 • (0.5)4

or 6.25 times the luminosity of the Sun.

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