| A | B |
|---|
| satellite | an object that revolves around a larger body |
| space shuttle | a reusable craft designed to transport astronauts, materials, and satllites to and from space |
| space probe | spacecraft equipped with instruments designed to collect information about outer space |
| gravity | the mutual force of attraction that exists between all objects in the universe |
| weightlessness | being in a state of apparent lack of gravitational pull |
| sundial | a tool that shows the time of the day by the position and length of the shadow the sun casts on a surface marked with numbers |
| sextant | an instrument used mainly in navigation for measuring the altitude of the sun or a star to determine the position of the observer |
| constellation | a visual pattern of stars |
| universe | all that exists, including Earth and all of space |
