This question is about stars and their radiation. (The Stefan-Boltzmann constant is σ=5.67×10−8 W m−2 K−4\sigma = 5.67 \times 10^{-8} \text{ W m}^{-2} \text{ K}^{-4}σ=5.67×10−8 W m−2 K−4.)
Use the data below to show that the luminosity of the star Procyon A is about 1.9 × 1027 W.
Vega, one of the brightest stars in the night sky, has a luminosity 40 times greater than that of Procyon A. It has a diameter 2.2 times greater than that of Procyon A.
Calculate the surface temperature T T\,T of Vega.
