Across
- 4. The shape of orbits in Kepler's model (10)
- 6. When a planet lies on a line between Earth and the Sun (11)
- 12. Formulated laws of gravitational motion (6)
- 17. A telescope with mirrors (9)
- 18. A space probe that crashes into a body (8)
- 19. Egyptian who refined geocentric model (7)
- 21. Big fan of Mars (5)
- 23. A day particularly short or long (8)
- 24. The shape of orbits in early models (8)
Down
- 1. Earth at the centre (10)
- 2. A small circle whose circumference moves around a larger one (8)
- 3. A space probe that lands on a body (6)
- 5. View an inferior planet when this is greatest (10)
- 7. Sun at the centre (10)
- 8. A telescope with lenses (9)
- 9. Published heliocentric thesis on deathbed (10)
- 10. The 'wobbling' of Earth's axis (10)
- 11. Motion that appears backwards (10)
- 13. A day and night of equal length (7)
- 14. What Aristotle believed made the planets orbit (5,5)
- 15. Greek philosopher who proposed geocentric model(11)
- 16. When a planet is closest to Earth (10)
- 20. A space probe that orbits a body (7)
- 22. A space probe that passes a body (5)