Spectra contain many bright lines.
Divided into WC (Carbon Sequence) and WN (Nitrogen Sequence)
Temperatures up to 80,000 C.
Spectra contain both bright and dark lines.
Temperatures between 40,000 and 35,000 C.
Prominent Helium lines.
Temperatures between 25,000 and 12,000 C.
Prominent Hydrogen lines.
Temperatures between 10,000 and 8,000 C.
Prominent Calcium lines.
Temperatures between 7,500 and 6,000 C.
Many metallic lines, weaker hydrogen lines.
Giants have temperatures between 5,500 and 4,200 C.
Dwarfs have temperatures between 6,000 and 5,000 C.
Strong metallic lines.
Giants have temperatures between 4,000 and 3,000 C
Dwarfs have temperatures between 5,000 and 4,000 C
Complicated spectra containing many lines due to molecules.
Giants have temperatures of 3,400 C.
Dwarfs have temperatures of 3,000 C
Type C (formerly types R and N):
Strong Carbon lines.
Temperatures between 5,000 and 2,000 C.
Prominent lines due to Titanium Oxide and Zirconium Oxide.
Temperatures of 2,600 C
Types L, Y, and Y:
Very cool Red Dwarfs and Brown Dwarfs.
T are the Methane Dwarfs.
Temperatures less than 2,00 C.
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