What is the meaning of OBAFGKM?
What is the meaning of OBAFGKM?
OBAFGKM
| Acronym | Definition |
|---|---|
| OBAFGKM | Oh, Be A Fine Girl/Guy, Kiss Me (mnemonic for the order of star temperatures) |
| OBAFGKM | Only Boys Accepting Feminism Get Kissed Meaningfully (mnemonic for the order of star temperatures) |
| OBAFGKM | Only Bad Astronomers Forget Generally Known Mnemonics (mnemonic for the order of star temperatures) |
Why are stars classified as OBAFGKM?
Fleming, assigned stars a letter according to how much Hydrogen could be observed in their spectra: stars labeled A had the most Hydrogen, B the next most, and so on through the alphabet. Her meticulous observations led her to simplify the 22-type scheme into a sequence of *temperature*: OBAFGKM.
How do you remember OBAFGKM?
The spectral sequence O B A F G K M. The classic mnemonic is Oh Be A Fine Girl, Kiss Me. You may replace girl with guy, depending on your sexual orientation, without changing the sense of the mnemonic.
What scientist came up with OBAFGKM?
What do the initials of “OBAFGKM” mean? A: It appears that when stars were first being classified in the 1890s, an astronomer at Harvard named Edward Pickering decided to sort the stars according to how much hydrogen they contained.
What type of star is the sun OBAFGKM?
Our Sun is class G2. Have a good look at Orion. Betelgeuse is a class M star whilst Rigel is a class B star.
What is the sun made of?
The sun is not a solid mass. It does not have easily identifiable boundaries like rocky planets like Earth. Instead, the sun is composed of layers made up almost entirely of hydrogen and helium.
What type of star lives the longest?
Red Dwarfs
Red dwarf stars make up the largest population of stars in the galaxy, but they hide in the shadows, too dim to be seen with the naked eye from Earth. Their limited radiance helps to extend their lifetimes, which are far greater than that of the sun.
Who was the first to scientifically categorize stars?
Known as the “census taker of the sky,” Annie Jump Cannon was a brilliant astronomer that revolutionized the way scientists classify stars. Not only did she develop the important Harvard spectral system, she also classified about 350,000 stars manually.
What is the relationship between a star’s temperature and expected life?
At the spot where the Sun is located, with 1 solar luminosity and a surface temperature of 6,000 K, stars live for about 1010 years, or 10 billion years. Stars that are hotter and more luminous than the Sun live for shorter times, while stars that are cooler and less luminous live for longer times.
What is the hottest type of sun?
Eta Carinae could be as large as 180 times the radius of the Sun, and its surface temperature is 36,000-40,000 Kelvin. Just for comparison, 40,000 Kelvin is about 72,000 degrees F. So it’s the blue hypergiants, like Eta Carinae, which are probably the hottest stars in the Universe.
https://www.youtube.com/watch?v=AJE_6E9LWNE
