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Stellar Luminosity Calculator

Calculate a star luminosity from its radius and surface temperature using Stefan-Boltzmann law.

Reviewed by Daniel Agrici, Founder & Lead Developer

Reviewed by Daniel Agrici, Founder & Lead Developer

Formula

L = 4ฯ€RยฒฯƒTโด | L/Lโ˜‰ = (R/Rโ˜‰)ยฒ ร— (T/Tโ˜‰)โด

Stefan-Boltzmann law: luminosity depends on surface area (Rยฒ) and temperature to the 4th power. Lโ˜‰ = 3.828ร—10ยฒโถ W, Tโ˜‰ = 5778 K.

Worked Examples

Example 1: Sirius A

Problem:R=1.71 Rโ˜‰, T=9940 K

Solution:L = 1.71ยฒ ร— (9940/5778)โด = 2.924 ร— 8.76 = 25.6 Lโ˜‰

Result:25.6 Lโ˜‰

Reviewed by Daniel Agrici, Founder & Lead Developer ยท Editorial policy