B-type main-sequence star

A B-type main-sequence star is a main-sequence (core hydrogen-burning) star of spectral type B. The spectral luminosity class is given as V. These stars have from 2 to 18 times the mass of the Sun and surface temperatures between about 10,000 and 30,000 K.

B-type stars are luminous and blue-white. Their spectra have strong neutral heliumabsorption lines, which are most prominent at the B2 subclass, and moderately strong hydrogen lines. Examples include Regulus, Algol A and Acrux.