1. Earth's Place In Space

4. Evolution

6. Atomic particles from the explosion later formed galaxies, stars, and planets.

8. A supernova occurs at the end of a stars life, releasing huge amounts of energy.

10. A solar nebula is thought to be a spinning cloud of dust and gas.

12. The other lumps of matter that formed from the contracting dust and gas became the planets.

14. As the Earth cooled

15. enough to form a

16. solid crust, it was

17. covered with active

18. volcanoes.

22. Oxygen was released as a byproduct.

24. This allowed for plant life to evolve and made it possible for the evolution of animal life on land.

27. Cenozoic: Early humans/Modern Humans