| A | B |
|---|
| apparent magnitude | the measure of how bright a star appears to be |
| absolute magnitude | a measure of how bright a star really is |
| light-year | the distance light travels in one year |
| nebulus | huge clouds of gases and dust |
| protostar | pockets of matter that forms a star |
| red giant | a very large old reddish star that has greatly expanded and cooled as its fuel has begun to run out |
| white dwarf | a very small dying star that gives off little light |
| black dwarf | the cool dark body that is the final stage of a star |
| supernova | en exploding star |
| neutron star | the remains of a massive star that has exploded in a supernova |
| black hole | a collapsed or tiny region |
| milky way galaxy | a gigantic cluster of stars that make up our home |
| galaxy | a huge collection of stars |
