Across
- 2. Force of attraction
- 5. The gradual changing of ecosystems
- 7. Type of large planet that is made mostly of hydrogen and helium
- 10. _____ flows through a system
- 11. Type of large planet that is made mostly of nitrogen, carbon, oxygen, and sulfur
- 14. Ribbons of green to red light formed when solar winds hit the earth’s magnetic field.
- 15. The earth is found in a ___ of the Milkey way galaxy
- 16. Semi-molten, plastic layer beneath the lithosphere
- 20. Fourth planet from the sun
- 22. Type of galaxy with older stars and little dust left
- 23. All of the water on earth (97% saltwater and 3% freshwater!)
- 25. Seasons are caused by the ____ of the planet
- 28. Process by which plants convert carbon dioxide and water into food using sunlight
Down
- 1. Most common element
- 3. All the non-living things in an ecosystem
- 4. Type of planet with a solid surface
- 6. Collection of billions of stars and their planets
- 8. Area of space with lots of hydrogen-- where stars are likely to form
- 9. All the living organisms on the planet
- 12. The earth represents a ___ system
- 13. How light and energy travel through space
- 17. Type of galaxy with younger stars and lots of space dust
- 18. Dwarf planet that used to be the ninth planet from the sun
- 19. Matter ____ through a system
- 21. Instead of using light, ____ uses hydrogen sulfide to produce food
- 24. Like a planet, but smaller and has other space objects in its orbit path
- 26. Transition from earth’s atmosphere to space helps block solar radiation
- 27. all the living things in an ecosystem