Across
- 4. The planet most similar in size to Earth
- 6. A cloud of dust and gas in space
- 9. The name for the study of the origin and structure of the universe
- 10. The name of our galaxy
- 11. The name of the path a planet takes around a star
- 12. The largest planet in the solar system
- 13. A small rocky object orbiting a star
- 15. An object that orbits a planet
- 17. The closest star to Earth
- 18. The name of the force that holds the solar system together
Down
- 1. A small icy object that orbits a star
- 2. The process a star uses to produce energy
- 3. The closest planet to the Sun
- 5. A region of space with gravity so strong not even light can escape
- 7. The name of the man-made object that has travelled furthest into space (no number)
- 8. The number of planets in the solar system
- 14. Caused by the explosive death of a massive star
- 16. the distance light travels in one year