The classification of stellar spectra started with the amount of hydrogen in the star's spectrum; however, now a better scheme uses the star's _____.
A) mass
B) diameter
C) radius
D) temperature
E) luminosity

Question

Quizplus · Accepted Answer

The classification of stellar spectra is primarily based on the star's temperature. This scheme, known as the Harvard spectral classification, orders stars according to their surface temperatures, which significantly influence the absorption lines visible in their spectra.

The Classification of Stellar Spectra Started with the Amount of Hydrogen