| A | B |
|---|
| red shift | occurs when a star moves away from the Earth |
| hydrogen | 1st element in the universe |
| spectroscope | instrument used to split white light into all of its colors, and determine what elements are present in a star |
| nulcear fusion | turns hydrogen to helium |
| gravity | force based on the amount of matter something has |
| Local Group | group of 45 galaxies |
| magnitude | brightness of a star |
| parallax | shift in a star's location, used to measure distance to a star |
| electromagnetic spectrum | complete range of wavelengths emitted by a star |
| light-year | unit used when measuring distance to a star |
| background radiation | left over energy from the Big Bang that has been stretched from gamma rays to microwaves |
| the sun | our closest star, has a life-span of 10 billion years |
| Milky Way | our spiral galaxy |
| nebula | cloud of gas and dust in space |
| quasar | galaxy that is just forming and emitting lots of energy |
| red stars | cool stars |
| blue stars | hot stars |
| white light | light that contains all of the colors in the rainbow |
| main sequence | diagonal band of stars on a H-R diagram; these stars are burning hydrogen |
| white dwarfs | small, hot, dim stars in the lower left of the H-R diagram |
