Across
- 3. a small body of matter from outer space that enters the earth's atmosphere
- 7. space rocks
- 9. about the same mass as a proton but without an electric charge
- 10. space research
- 13. earth science
- 15. The fifth planet
- 17. state of matter
- 18. Only Saturn has..
- 19. state of matter
- 20. based on or characterized by the methods and principles of science
Down
- 1. positive electric charge
- 2. the force that attracts a body toward the center of the earth
- 4. the process of eroding or being eroded by wind, water, or other natural agents
- 5. a group of atoms bonded together
- 6. a basis for reasoning
- 8. facts and statistics
- 11. looking at something to gain information
- 12. systematic investigation
- 14. state of matter
- 16. Our Planet