Across
- 2. a space that does not contain any matter
- 4. Earth’s most distant point
- 7. amount of time a planet takes to complete its orbit
- 8. sun centered
- 9. symmetrical oval
- 10. closest point to the sun
- 11. circle around due to gravity
- 13. this astronomer proposed the heliocentric theory
- 14. developed the law of gravity
- 15. our galaxy
Down
- 1. this astronomer agreed with Copernicus
- 3. the force of gravity depends on___________and distance
- 4. popularized the geocentric theory
- 5. Kepler developed__________laws of planetary motion
- 6. earth centered
- 10. this astronomer assumed that the planets traveled in small circles called epicycles
- 12. the study of God’s creation beyond our atmosphere