Astrophysics (Index)About

B-type star

(B, B-class star)
(star with spectral characteristics of around 10000-30000 K)

A B-type star is a star within the B-class, a spectral class indicating stars with neutral helium and moderate hydrogen absorption lines, a blue-white color, and a surface temperature in the general range of 10,000 K to 30,000 K. The spectral energy distribution peaks in the ultraviolet. Main sequence stars of this class are on the order of 10 solar masses, 5 times solar radius, and hundreds to thousands of times as bright as the Sun. Such main sequence stars burn their hydrogen on the order of a hundred million years. Characteristics of B-type main sequence stars:

1.25 to -6.12absolute magnitude(visual)
25-30000bolometric luminosity(solar)
10 million-1.5 billion yearsmain-sequence lifetime
0.13%fraction of MS stars

Blue giants (and blue supergiants) are very hot giant stars, which can fall in this temperature range and be classified as B-type stars. Example B-type stars are Achernar, Algol, Beta Centauri (pair of giant stars), and Rigel (includes a supergiant).

(star type,spectral class)
Further reading:
97nm3.1PHz13eVbeginB-type star
145nm2.1PHz8.6eVendB-type star

Referenced by pages:
Ap star
Be star
Beta Centauri
giant star
Gould's Belt
helium star
Herbig AeBe star (HAeBe)
OB association
OB star
Pleiades (M45)
red giant
red-giant branch (RGB)
star formation rate (SFR)
shell star (sh)
solar wind
spectral class
stellar association
subdwarf (sd)
variable star
WR 104
young stellar object (YSO)