| A | B |
| satellite | a man-made object that revolves around a larger boy, may send information back to Earth |
| solar system | the system of object in orbit around the sun |
| space probe | spacecraft equipped with instruments designed to collect information about outer space |
| space shuttle | a reusable craft designed to transport astronauts, materials and satellites to and from space |
| universe | all that exists, including Earth and all of space |
| Milky Way | the galaxy that contains our solar system |
| quasar | a very bright center of a distant galaxy that is in the beginning stages of being created |
| star | a huge ball of gas |
| asteroid | fragments of rocky matter that orbit Mars and Jupiter |
| black hole | a star in which matter is condensed and its gravity field so strong that light cannot escape |
| comet | a mass of frozen gases, dust, and small rock particles that orbits the sun; it has a shiny tail |
| constellation | a visual pattern of stars |
| galaxy | large system of gas, dust, and many stars; there are 4 types |
| meteor | meteoroids that burn up in the Earth's atmosphere |