Which spectral luminosity class corresponds to a red supergiant?
A) M2 I
B) B7 I
C) M3 V
D) G2 III

Question

Quizplus · Accepted Answer

Red supergiants are large, cool stars with low surface temperatures and high luminosities. The spectral luminosity class that corresponds to this type of star is an I in the MK spectral classification system which indicates a luminous supergiant star. The M2 spectral class corresponds to an effective temperature of around 3,500K which is consistent with the cool temperatures of red supergiants. Therefore, choice A) M2 I is the best choice.

Which Spectral Luminosity Class Corresponds to a Red Supergiant