1. Science’s explanation of how the universe originated
The Big Bang Theory
Science’s explanation of how the universe originated

2. Large and violent explosion 13.7 billion years ago

3. This created many clouds of gas and dust
Those clouds accreted to form solar systems and eventually galaxies
ALL the elements came from this explosion, mostly H and He at first

4. heavier elements formed later (inside the stars)

5. the universe continues to expand, evolve, and cool
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6. Quickly look over your notes and then summarize important concepts
60 second summary
Quickly look over your notes and then summarize important concepts

7. Review #1What does the big bang theory try to explain?
how the universe began

8. Review #2What does accretion mean?
to clump together and stick

9. Review #3 Which 2 elements were there the most of after the big bang?
H and He

10. evidence: recent data show low-level microwave radiation in the universe, only 3K, background “noise”
this radiation is left over from the big bang
as the universe expanded and cooled, the radiation waves stretched out