Chapter 8 Crossword

4. The first ______ were formed by heavy rains for 10 million years.
6. By looking at ______ in Australia, scientists are trying to find the age of the earths crust.
7. The Earth is 4.6 _______ years old.
8. The first clouds on Earth were formed by steam released from ________.
9. The Earths iron core creates a magnetic field to protect it from solar ____.
10. The process by which volcanoes steam created clouds is called __________.
14. When the surface of the Earth was completely molten, it was known as _____ ocean.
15. The Big Bang Theory is about the creation of the ________.
16. The explosion of a star is called a _________.
18. The Milky Way is the ______ that contains the earth.

1. as the Earth grew older, the ____ moved further away.
2. Six million years from now the sun will _______ from consuming other planets.
3. The process by which the planets solidified.
5. Small early planets the formed from gravitational attraction.
11. When _____ get extremely old they turn into a red giant.
12. Scientists can determine a meteors ___ by the radioactive elements found in the meteors.
13. These were similar to the first organisms found on earth.
17. this planet was believed to have once had water.