Across
- 4. recorded oldest known record of a comet sighting
- 6. discovered the sun is powered by nuclear energy
- 9. means "rebirth"
- 13. (2W)primarily used eye-sight and record-keeping
- 17. mathematical view of earth-centered universe in AD 150
- 18. concluded that the speed of light is a universal constant
- 20. cataloged many of the deep space objects studied in astronomy today
- 22. used water clocks to count out time
Down
- 1. described earth as a round object
- 2. developed an accurate model of the universe and the forces working within it
- 3. believed the planets revolved around the sun
- 5. calculated the average lunar month almost precisely
- 7. recorded the first supernova
- 8. (2W)used celestial navigation to find the baby born king of the Jews
- 10. published a detailed map of the moon's surface
- 11. first astronomer to successfully photograph sunspot spectrums
- 12. developed mathematical law describing elliptical planetary orbits
- 14. scientific study of celestial objects
- 15. can reveal the temperature of a star, chemical composition, etc.
- 16. they discovered the planet Uranus
- 19. means "star"
- 21. first published telescope observations of the universe