Chapter 8 Crossword

4. When _____ get extremely old they turn into a red giant.
8. The Big Bang Theory is about the creation of the ________.
10. Scientists can determine a meteors ___ by the radioactive elements found in the meteors.
12. Small early planets the formed from gravitational attraction.
14. These were similar to the first organisms found on earth.
15. Six million years from now the sun will _______ from consuming other planets.
17. as the Earth grew older, the ____ moved further away.

1. this planet was believed to have once had water.
2. By looking at ______ in Australia, scientists are trying to find the age of the earths crust.
3. The first ______ were formed by heavy rains for 10 million years.
5. The explosion of a star is called a _________.
6. The process by which the planets solidified.
7. The process by which volcanoes steam created clouds is called __________.
9. The first clouds on Earth were formed by steam released from ________.
11. When the surface of the Earth was completely molten, it was known as _____ ocean.
13. The Milky Way is the ______ that contains the earth.
14. The Earth is 4.6 _______ years old.
16. The Earths iron core creates a magnetic field to protect it from solar ____.