Across
- 3. small parts or pieces that are left over after the main part is gone
- 4. something that occurs or takes place
- 8. a gas that is lighter than air, has no color or smell, and is used as a fuel
- 10. an object in space formed when a star breaks down
- 13. plant life or all the plants in an area
- 14. very destructive weapons that get their explosive power from the splitting of atoms
- 15. believable or likely but not certain
- 18. a large number or amount that is more than enough
- 20. a large gathering or collection of something
- 22. objects that move through space and are made of ice, frozen gas, and dust
- 23. far away from other things
- 24. burned the outside of something
- 25. came into being, usually as a result of something
- 27. passed from person to person
Down
- 1. the use of science to solve problems or make tasks easier
- 2. inventions or machines made for a certain job or purpose
- 5. a bowl-shaped pit that is caused when something slams into the surface
- 6. possible sequences of events
- 7. a possible explanation or a guess mad after observation and careful thought
- 9. equal in value, amount, or some other measure
- 11. an unidentified flying object
- 12. usually or most of the time
- 16. later or happening after
- 17. people who point out the good and bad parts of something
- 19. the amount of harm or difficulty that something causes
- 21. strong, sharp, or extreme
- 26. a piece of rock or metal that has fallen to Earth from outer space