- A B-type main-sequence star (B V) is a main-sequence (hydrogen-burning) star of spectral type B and luminosity class V. These stars have from 2 to 16 times the mass of the Sun and surface temperatures between 10,000 and 30,000 K. B-type stars are extremely luminous and blue. Their spectra have strong neutral helium absorption lines, which are most prominent at the B2 subclass, and moderately strong hydrogen lines. Examples include Regulus, Algol A and Acrux.
- Girtab (stars.astro.illinois.edu)
GIRTAB (Theta Scorpii). Girtab, Bayer’s Theta star within Scorpius, the celestial scorpion, stands out in almost any way you can look at it. The name alone is unusual, in that it comes to us from Sumerian rather than Arabic or Greek, and means simply “the scorpion.”