How did the Universe Form?

1. How did the Universe Form?

2. The universe formed 14 billion years ago from an explosion referred to as the Big Bang • The universe is constantly expanding • http://www.brainpop.com/science/space/bigbang/zoom.weml

3. How did our solar system form? • Our solar system formed when the Big Bang explosion cooled.

4. How did Earth form? • Earth formed when dust, gases, and ice particles from the Big Bang collided, 4.6 billion years ago (4,600 million years ago). • http://www.teachersdomain.org/ext/ess05_img_walloftime/index.html

5. What keeps Earth from being bombarded with space debris? • Earth’s atmosphere and magnetic field protects it from being bombarded by space debris.

6. When did humans appear on Earth? • Humans appeared on Earth very, very recently; about 100,000 years ago.

7. How do we know what life existed on Earth before humans? • Fossils tell us what life forms existed before humans.

8. What is a fossil? • http://www.brainpop.com/science/diversityoflife/fossils/quiz/

9. A fossil is… • Body fossil- • Trace fossil- • Mold- • Cast- • Petrified fossil-

10. A fossil is the preserved remains or traces of an organism that lived in the past.

11. Body fossil- part of original organism that has been preserved; ex: bug in amber, mammoth in ice; saber-toothed tiger in tar pit

12. Petrified fossil- formed when minerals slowly replace an organism

13. Mold- hollow print, impression in sediment which turns to rock

14. Cast- when minerals fill in a mold and harden into rock; 3-D

15. Trace fossil- footprints, nests, bite marks, poop (what an animal could leave behind)

16. How are fossils formed? • http://www.teachersdomain.org/folder/view/3748/

17. How can we find out how old a fossil is? • http://www.teachersdomain.org/resource/tdc02.sci.phys.matter.radiodating/

18. What can fossils tell you about how life changed through time?

19. What are some things that you want to understand better about fossils and changes in life through time?