| A | B |
|---|
| Meteor | a piece of space debris burning up in Earth's atmosphere |
| Asteroid | a rock in space |
| Comet | a ball of ice from Deep Space |
| Copernicus | developed the modern theory of the Sun centered Solar System |
| Oort Cloud | where comets come from; located and the edge of our Solar System |
| main sequence | a level of classification for stars; as stars get hotter they get brighter in this level |
| dwarf star | a level of classification for a hot, dim star |
| Giant or Super Giant Star | a level of classification for stars that are cooler in temperature, but still very bright |
| black hole | and area in space where gravity prevents light from escaping |
| hydrogen | the most abundant element in the universe; fuel source for stars |
| nuclear fusion | process that forms stars |
| galaxy | a group of billions of stars located in a region of space |
| apparent magnitude | how bright a star appears to be from earth's view |
| absolute magnitude | how bright a star actually is compared to every other star |
| Big Bang Theory | a theory explaining how the Universe may have formed |
| Nebula | a cloud of dust and gases in space that will eventually become a star |
