Blue Supergiant

Blue Supergiant

Blue supergiants (BSGs) are hot luminous stars, referred to scientifically as OB supergiants. They have luminosity class I and spectral class B9 or earlier.

They are found towards the top left of the Hertzsprung-Russell diagram to the right of the main sequence. They are larger than the sun but smaller than a red supergiant, with surface temperatures of 10,000–50,000 K and luminosities from about 10,000 to a million times the sun.