Notes on Stellar Spectra

1.) A hydrogen light spectra are more likely to appear on earth.
2.) Closer stars because the difference in position is more noticeable.
3.) Apparent brightness
4.) Hydrogen, many atoms fuse together to make helium which burns very hot and the interactions keep multiplying as more and more helium atoms are made, throwing off a hydrogen atom.
5.) Intensity is how bright the star appears and magnitude is how bright it actually is.