Stellar Luminosity Calculator

Calculate the luminosity of a star relative to the Sun using the Stefan-Boltzmann law, given its radius and surface temperature.

Results will appear here.

Formula

Stefan-Boltzmann Law:

L = 4π R² σ T⁴

Where:

  • L = Stellar luminosity (Watts)
  • R = Stellar radius (meters)
  • σ = Stefan-Boltzmann constant = 5.6704 × 10⁻⁸ W m⁻² K⁻⁴
  • T = Effective surface temperature (Kelvin)

Relative to the Sun:

L / L☉ = (R / R☉)² × (T / T☉)⁴

Where T☉ = 5,778 K and R☉ = 6.957 × 10⁸ m.

Bolometric Absolute Magnitude:

M_bol = 4.74 − 2.5 × log₁₀(L / L☉)

Assumptions & References

  • References: Carroll & Ostlie, Introduction to Modern Astrophysics; IAU 2015 Resolution B3.