Astrophysics (Index)About

carbon star

(C, C-type star)
(star with more carbon than oxygen in its atmosphere)

A carbon star is a star with more carbon than oxygen in its stellar atmosphere. The spectral class C (for C-type star) indicates a star with molecular carbon lines, indicating such a star. Their effective temperature can be anywhere from within the range of M-type stars to G-type stars. Carbon and oxygen in a star's atmosphere forms carbon monoxide, and if carbon is left over, other carbon compounds are formed, giving the star a red appearance (most stars, including the Sun, have more oxygen than carbon in their atmospheres). One situation where stars form more-than-usual carbon is thought to be asymptotic giant branch (AGB) stars with helium producing additional carbon through helium fusion. Another means is accretion from a binary companion. Carbon stars can emit carbon in their stellar wind, leading to carbon in cosmic dust. Some related terms:

(For each of these terms, whether it can be called a subclass of carbon star, versus some other star type that has some carbon is a matter of semantics: the term carbon star is probably often used specifically for certain well-known types/scenarios.)


(star type,carbon,spectral class)
Further reading:
https://en.wikipedia.org/wiki/Carbon_star
https://en.wikipedia.org/wiki/Stellar_classification#Class_C
https://en.wikipedia.org/wiki/CEMP_star
https://dictionary.obspm.fr/index.php?showAll=1&formSearchTextfield=carbon+star
https://www.daviddarling.info/encyclopedia/C/carbon_star.html
https://lweb.cfa.harvard.edu/~pberlind/atlas/htmls/cstars.html
https://www.johncbarentine.com/carbon-star-list.html

Referenced by pages:
binary star
chemically peculiar star (CP star)
PAH emissions
rare designator prefixes
spectral class
technetium star

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