O stars

http://astrothesaurus.org/uat/1137

alt label
Class O stars
O-type stars
dcterms modified equal to or less than 2020-11-03T19:46:55.553Zequal to or more than 2020-11-03T19:46:55.553Z
broader
http://astrothesaurus.org/uat/2051 original
narrower
1137 original
http://astrothesaurus.org/uat/430 original
narrower
1137 original
definition A luminous, hot, blue star whose spectrum is dominated by the lines of hydrogen, atomic helium, and ionized helium; also known as O-type star. This is the earliest spectral type and the only main sequence star in which ionized helium is present. The effective temperatures of these stars range from about 30,000 K to 50,000 K, their luminosities from 50,000 to 1,000,000 times that of solar luminosity, and their masses from about 20 to 100 solar masses. The hottest O-type stars display high ionization emission features such as N III and He II, Of star. They are divided into subtypes O2, the hottest, to O9.7, the coldest. O-type stars are relatively rare, for each star of 100 solar masses there are 10^6 stars of solar mass. They are relatively short-lived since they spend only a few million years on the main sequence. The brightest O-type star in the sky visible with naked eye is Alnitak.
narrower
http://astrothesaurus.org/uat/1132 original
broader
1137 original
http://astrothesaurus.org/uat/1135 original
broader
1137 original
http://astrothesaurus.org/uat/1136 original
broader
1137 original
http://astrothesaurus.org/uat/1138 original
broader
1137 original
http://astrothesaurus.org/uat/1139 original
broader
1137 original
http://astrothesaurus.org/uat/1153 original
broader
1137 original
http://astrothesaurus.org/uat/1154 original
broader
1137 original
http://astrothesaurus.org/uat/1155 original
broader
1137 original
type
Resource original
Concept original
contributor AAS_Frey.Katie_Admin original