| Word | Meaning |
| Nebula | A vast cloud-like mass of gas and dust particles in space |
| Eddy current | The swirl set up as matter collects, which makes the centre spin |
| Centrifugal force | The force that pushes the matter of a spinning body outwards |
| Equator | The middle circle of a spinning ball, the line from which the rings were flung off |
| Comet | A heavenly body with a long tail |
| Filament | The long tongue of hot matter drawn out of the sun by a star's pull |
| Asteroid | A small body revolving round the sun that never grew into a planet |
| Revolution | The motion of one body going round another body |
| Fossil | The remains of ancient living things preserved inside rock, from which age is read |