| A | B |
|---|
| elliptical | oval-shaped like a flattened circle |
| model | a representation of how something looks or works |
| asteroid | a rocky object that revolves around the sun |
| meteoroid | a small piece of rock and metal that travels in space around the sun |
| meteor | a bright streak of light that passes through Earth's atmosphere |
| comet | a ball of ice, dust, and gases that travel through space and orbit the sun |
| meteorite | a piece of a meteor that lands on Earth after passing through the atmosphere |
| light year | the distance light travels in one year |
| constellation | stars that appear to be in groups when viewed from Earth |
| galaxy | a group of billions of stars, dust, and gases in space held together by gravity |
| spectroscope | an instrumenrt that separates light into a pattern of lines of different colors |
| refraction | the bending of light as it passes from one material to another |
| reflection | the bouncing of light off a shiny surface |
