Across
- 3. center of the solar system according to Ptolemy
- 6. this scientists' model of the solar system finally explained the precession in Mercury's orbit
- 7. used Brahe's measurements to determine that orbits are ellipses
- 8. Kepler's 2nd Law: a planet sweeps out equal areas in ___ time
- 9. the location in an orbit farthest from the sun
- 10. Kepler's 3rd Law: The ____ squared equals the semi-major axis cubed
- 14. Tycho Brahe lost his ____ in a duel
- 15. This scientists' early model of the solar system only accounted for the planet's speeds
Down
- 1. popularizer of the heliocentric theory
- 2. the eccentricity of many comets orbits is nearly equal to ___
- 4. the location in an orbit closest to the sun
- 5. Kepler's 1st Law: Planets move in ___ with the sun at one focus
- 11. first theory of what makes planets go around the sun
- 12. ___ and epicycle: Ptolemy's mechanism for explaining retrograde loops
- 13. maade fantastically accurate measurements without a telescope