2004.11.18 Stellar Spectral Types: OBAFGKM

Explanation: Astronomers divide stars into different spectral types. First started in the 1800s, the spectral type was originally meant to classify the strength of hydrogen absorption lines. A few types that best describe the temperature of the star remain in use today. The seven main spectral types OBAFGKM are shown above with the spectrum of a single "O" star at the top followed by two spectra each from the progressively cooler designations, respectively. Historically, these letters have been remembered with the mnemonic "Oh Be A Fine Girl/Guy Kiss Me." Frequent classroom contests, however, have come up with other more/less politically correct mnemonics such as "Oven Baked Apples From Grandpa's/Grandma's Kitchen. Mmmm." Our Sun has spectral type "G". 

천체물리 수업을 들을때 보았던 별들을 분류하는 방법 중의 하나.
Oh Be A Fine Girl Kiss Me! ㅋㅋ.. 재밌다.

Credit & Copyright: KPNO 0.9-m Telescope, AURA, NOAO, NSF 
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