Glossary term: O-type Star
Description: An O star is one whose "surface" temperature (the temperature of the layer in the star from which its light is emitted also known as effective temperature) is greater than approximately 30,000 kelvins. An O-star is identified by the absorption lines in its spectrum including ionized helium lines. O stars are the hottest and bluest of the main spectral classifications. O stars on the main sequence have the shortest hydrogen burning lifetime and as a result are mostly found in and around star forming regions.Related Terms:
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Term and definition status: This term and its definition is still awaiting approval
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