Stellar classification (astrophysics)
Jump to navigation
Jump to search
Stars are classed by various properties. A common classification is surface temperature. Beginning with early spectral schema in the 19th century ranking stars from A to P, the spectral classification, called “Morgan-Keenan spectral classification” [1][2] now ranks stars in seven main types: A, B, A, F, G, K, M.[3] Each spectral classification is further divided into tenths. Our sun, Sol is a G2.
Classification system
The stars are ranked from hottest to coldest:
Class Temperature Star colour
- O 30,000-60,000 °K Blue
- B 10,000-30,000 °K Blue
- A 7,500-10,000 °K White
- F 6,000-7,500 °K White (yellowish)
- G 5,000-6,000 °K Yellow (e.g. Earth’s sun)
- K 3,500-5,000 °K Orange
- M 2,000-3,5000 °K Red
References
- ↑ Note: based on the work of Annie Cannon and other astronomers from the Harvard College Observatory
- ↑ Annie Jump Cannon 1983-1941
- ↑ A popular mnemonic for this is Oh Be A Fine Girl, Kiss Me
- ↑ Star classification