Across
- 2. A natural satellite of a planet
- 5. Someone who studies and observes celestial bodies
- 6. A fixed path taken by a planet moving around the Sun
- 10. The movement of an object turning on an axis
- 12. An object in space that revolves around another object
Down
- 1. A system of planets revolving around the Sun
- 3. A self-luminous celestial body
- 4. The natural pull exerted by objects on one another
- 7. A single or complete cycle of an orbital motion
- 8. A natural pull caused by gravity
- 9. A celestial body that obits around a star
- 11. An imaginary straight line through the centre of the Earth