Across
- 3. the First half of the moon phases
- 5. _______ Laws, determine the shape of an orbit
- 9. object spinning around a central point
- 10. A hydrogen fusing with a hydrogen will give you what element?
- 11. A downward force that pulls objects toward the center
- 12. The center of an atom
- 14. The atomic number is equal to the number of _____
- 15. the shape of an orbit
- 16. Inner planets that are made of rocks or metal
- 18. ________ fusion is how stars create energy and light
- 20. Helium fused with carbon will give you ______
- 21. A technique astronomers use to measure the distance from stars to earth
- 22. The number of protons an iron atom has
- 24. Dark flat planes of the moon
- 27. Substance with atoms that have the SAME number of protons
Down
- 1. The ______ Space Station is a laboratory in space
- 2. Young stars are mostly ______ and helium
- 4. Brightness of stars from Earth
- 6. Smaller planets will have ______ gravity than larger planets
- 7. Outer planets, gas giants
- 8. The hottest stars are what color?
- 13. composition of stars is measure with a _____
- 17. The coolest stars are what color?
- 19. In order for fusion to occur, the temperature must reach ten ___ degrees Celsius
- 23. A light year is the distance light travels in a _____
- 25. Actual brightness of stars
- 26. Model that states the sun as the center of the solar system