Coolest stars - levels have higher temperatures ii X-ray...

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Coolest stars 1. Has alternative spectral types reflecting the relative abundance of elements. 1.i. Type L – temp about 1500K, has molecular spectrum lines from iron hydride and calcium hydride (brown dwarfs). 1.ii. Type T – cooler than Type L and has spectrum lines from methane molecules 2. Example: a star relatively high in carbon is called a carbon star . 3. These lower temperature stars bridge the gap between and planets. Special cases 1. Wolf-Rayet stars i. O Type ii. Very wide emission spectrum. iii. Comes shells of material ejected from the star. iv. Very strong solar wind. v. Mass loss varies from spectral type to spectral type. <Who was Ceclia Payne and what was her contribution to society?> 2. Spectra observed from space i. By observing x-ray, ultraviolet and or spectrum from outside the earth. Atmosphere, we can observe the spectrum above the stars surface. Higher
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Unformatted text preview: levels have higher temperatures. ii. X-ray observations ii.a. Class M – have a 10% x-ray spectrum compared to its visible spectrum. Class M stars are to cool for that much x-ray emission from surface. ii.b. Comes from Stellar Coronas with a temp. of 1,000,000˚k magnetic waves. iii. Ultraviolet observations iii.a. Can pick up spectral line from a temp. of 250,000˚. iii.b. Come from Stellar Chromospheres/Transition zone between surface and corona. H-R Diagrams – a graphical representation of the relationship or absolute magnitude, temperature, color and spectral type of stars. There are four major sections on an H-R Diagrams: Supergiants, Giants, Dwarfs (main Sequence) and White Dwarfs. Mass-Luminosity Relationship . Main sequence – Dwarf Dwarf stars Giants Super giants White dwarf...
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Coolest stars - levels have higher temperatures ii X-ray...

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