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physical object > natural object > celestial body > star > late star > carbon star > C star

C star
subject			fact

C star	has definition A class of carbon star, defined by Morgan and Keenan to replace the Harvard R and N spectral classes.
	has definition Late type giant with strong bands of carbonated molecules (C2, CN, CH) and no metallic oxide bands. Formerly they were called R or N types, the R types being the hotter and the N types the cooler C stars.
	is a kind of carbon star
late star	has spectral type cooler than G2
star	has star surface temperature
	has V magnitude
	has B magnitude
	has U magnitude
	has position on celestial sphere from the point of view of Earth
	has parallax from the point of view of Earth's orbit
	has proper motion
	has radiation at surface which is diffused out from the hotter core
	has energy source gravitational contraction and or fusion
	has energy production which takes place primarily within the core
	has surface density which depends on luminosity class
	has surface temperature greater than 1000 Kelvin
	has apparent magnitude
	has absolute magnitude
	has age
	has catalog star catalog
	has material hydrogen, helium
	has velocity determined from proper motion and radial velocity
	has mass greater than 0.08 the sun's mass
celestial body	has spectra
physical object	has location or center of gravity
	has angular momentum
	has momentum
	has temperature
	has volume
	has extent

Kinds of C star :

• hydrogen-deficient C star (2 kinds, 21 facts) - A subgroup of high-luminosity C stars with weak or absent hydrogen lines, mostly of types F and G.
• lithium star (1 kind, 7 facts) - C star with a very strong Li I 6078 line., Peculiar giant star (spectral types G-M) whose spectra show high abundances of lithium. They are primarily S stars and carbon stars, although Li is also found in T Tauri stars, and is sometimes observed in normal late-type giants. Interstellar Li / H ≈ 2 × 10^-10. (Solar system Li / H ≈ 10^-9.) Lithium is destroyed rapidly (in about 7500 years) at typical nuclear burning temperatures. Spallation is the only production mechanism known for ⁶Li, but ⁷Li can be transported from the core in the form of ⁷Be and converted in the envelope to ⁷Li by electron capture. Observed ⁷Li / ⁶Li > 10.
• N star (3 facts) - Red star similar to M stars except that bands of C₂, CN, and CH are present instead of those of TiO. N stars are strongly concentrated toward the Galactic plane., In the old terminology, the cooler C-type stars.
• R star (2 facts) - Star with spectral characteristics similar to those of K stars except that molecular bands of C₂, CN, and CH are present instead of TiO bands.

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