Across
- 4. he created the laws of planetary motion
- 7. a mathematician and astronomer who formulated a model of the universe that placed the sun rather than the earth at its center
- 8. when 2 or more atomic nuclei collide while at a high speed and together form a new kind of atomic nucleus
- 9. when the moon blocks the sun from the earth
- 11. also known as a degenerate dwarf. a stellar remnant composed mostly of electron-degenerate matter
- 13. stars that have a lifetime that can range between 50 million to 20 billion years
- 18. an early stage in the process of star formation formed from the gas of a giant molecular cloud
- 19. bright balls of gas in the sky
- 20. the smallest and densest stars known to exist in the universe
- 22. an explosion that periodically shines brighter than an entire galaxy
- 24. the change in frequency of a wave for an observer moving to the source
- 25. the matter that is in the space between the different star systems in a galaxy
Down
- 1. places with such a gravitational pull that nothing can escape
- 2. when the earth is blocking the sun from the moon
- 3. an Italian astronomer who played a major role in the scientific revolution during the renaissance. He improved the telescope
- 5. the angle between an objects rotational axis and orbital axis
- 6. a telescope that uses infrared light to find celestial bodies
- 10. stars that spend many years fusing hydrogen to helium in their cores
- 12. is a scattered graph of stars
- 14. a small and relatively cool star on the main sequence
- 15. an astronomer and writer who wrote many scientific books
- 16. a white dwarf that has sufficiently cooled that it no longer emits significant heat or light
- 17. an intersteller cloud of dust and oter ionized gases
- 21. stars that form like low mass stars except much quicker
- 23. a significant pattern of stars