Across
- 2. also called Tycho he studied astrology, alchemy, and medicine
- 4. drawn using string,pencil and two thumbtacks
- 7. total amount of matter
- 9. force of gravity
- 12. semimajor axis of earth's orbit around the sun
- 13. discovered the law of gravity
- 14. earth ray at center of universe
Down
- 1. earth is not the center of the universe
- 3. two bodies with equal masses under the influence of their mutual gravity
- 5. sun's inward pull of gravity on a planet
- 6. 4 moons of Jupiter
- 8. Italian philosopher created the telescope
- 10. considered a dwarf planet in our solar system
- 11. discovered the aberration of starlight
- 15. a tendency to do nothing or to remain unchanged