Across
- 4. The rapid increase in different species during the Phanerozoic Eon.
- 5. Fossil that includes only bones or teeth.
- 8. How tightly packed something is.
- 9. Meteor that crashes on Earth.
- 14. Humans.
- 15. The first step in planet formation.
- 17. The metric system unit measurement for length.
- 19. Study of fossils.
- 21. A large expanse of land.
- 22. The area of space where Pluto is located.
- 25. Egg that allows reptiles to live on land.
- 26. The system that includes all the frozen water on Earth.
- 27. The planet type Pluto is categorized as.
Down
- 1. The preserved remains of organisms.
- 2. Planet closest to the Sun.
- 3. The extinction that killed the dinosaurs.
- 6. The planet most explored besides Earth.
- 7. Statement of what you think will happen in an experiment.
- 9. The majority of species alive on Earth die.
- 10. Force that keeps the planets circling the Sun.
- 11. Animal that spends half its time on land and in the water.
- 12. Information you collect during an experiment.
- 13. The measurement of how much space a liquid takes up.
- 16. Type of planets made up of gas.
- 18. Walking up right.
- 20. Study of the ocean.
- 23. How long it takes a radioactive isotope to decay.
- 24. Study of tree rings.