1. Big Bang Theory Assessment

2. A Theory is Born
Big Bang-A theory that describes how the universe was created.

3. When Did This Event Occur
13.8 billion years ago (bya)
The universe was just energy before the explosion the size of an atom
The first elements created were hydrogen (H) and helium (He).
Hydrogen and helium are the most abundant elements found throughout the universe today.

4. Proof of the Big Bang Cosmic Background Radiation (microwaves)
This radiation was created at the initial bang and is found throughout the universe in all directions today.

5. Proof of the Big Bang Expanding universe
Telescopes were used to track the motion of galaxies. (Edwin Hubble)
Galaxies are moving at different speeds
Light spectra-spectral lines of stars and galaxies shift to either the blue or red side of the light spectrum.
Red shift-moving away, blue shift-moving towards

6. Birth of a Solar System
Our solar system was born 4.5 billion years ago