1. How Did the Universe Begin?

2. Background Info
There are many theories about how the Earth system originated.
Some are based on scientific fact
others are based on religion, and folklore

3. An Idea Edwin Hubble was an American astronomer who studied galaxies
Two significant findings
Confirmed that there are many galaxies other than the Milky Way (the galaxy we live in)
Galaxies are moving away from each other

4. The Big Bang Theory
The leading scientific theory for the origin of the Universe.

5. Building a Universe - infinitely dense point
- all matter and energy contained
in one point called a singularity
Einstein’s theory of relativity predicts this “smaller than a proton” time=0 state

6. Big Bang Theory of the Universe
About 13.7 Billion years ago the singularity began to expand
2. This matter cooled and began to quickly move apart

7. The Big Bang Theory
3. hydrogen and helium were the first atoms to form.
After 1 million years the gases began to gather together.

8. The Big Bang Theory 5. After 300 million years:
Gases clumped into clouds
Clouds clumped together to form stars and galaxies

9. The Big Bang Theory Video 1

10. Formation of our solar system

11. The Solar Nebula
The nebular theory - Solar System formed out of a nebula which collapsed under its own gravity.
solar nebula – name given to a cosmic cloud of gas from which our own Solar System formed

12. A huge rotating cloud of dust and gases (Nebula) begins to contract

13. Gravity forces most material to the center, producing the sun.
Some dust and gas remain orbiting the central body

14. The planets begin to form from the material that is orbiting

16. What is the estimated age of the universe?
Were stars and galaxies formed immediately after the Big Bang? Explain.
How is the formation of a star linked to the formation of the solar system