Across
- 7. Dark areas that form on the surface of the sun.
- 9. Earth and the other planets orbiting the sun.
- 11. Apparent shift in the position of the stars changing as the Earth moves.
- 12. When an object is farthest from the sun.
- 17. When particles attract every other particle.
- 18. A force that attracts objects due to their masses and distances.
- 19. An explosion release of energy that extends into outer space.
- 20. An act of turning.
Down
- 1. A concept used by historians.
- 2. A path that a body travel as it goes around another body.
- 3. The act of a fluid that is hot and has little density.
- 4. An explanation of what happens to the natural world.
- 5. When two or more low-mass atomic nuclei fuse to form another.
- 6. Extend outward about 100km
- 8. A cloud from where the solar system form.
- 10. The inward force causing an object to move in the inward force.
- 13. The sun and all the bodies that orbit the sun.
- 14. Large bodies where planets are formed.
- 15. The sun and the other planets orbiting the Earth.
- 16. When an object is closes to the sun.