OB star
hot, massive star of spectral types O or early-type B that form in OB associations
OB stars are hot, massive blue stars. They are stars of types O or B in the Hertzsprung–Russell diagram.
Like other giant stars they are short lived, and do not move far from where they were formed. During their lifetime, they emit huge amounts of ultraviolet radiation. This radiation ionizes the surrounding interstellar gas of the nebula, forming an H II region.
References
change- B. Cameron Reed (2003). "Catalog of galactic OB stars". The Astronomical Journal. 125 (5): 2531–2533. Bibcode:2003AJ....125.2531R. doi:10.1086/374771. S2CID 121285799.
Other websites
change- Scientia Astrophysical Organization's star classification page. [1] Archived 2006-01-29 at the Wayback Machine
- Philippe Stee's homepage: Hot and active stars research