1. Birth of a Theory
Chapter 30.4

2. The Universe & Beyond
Cosmology – study of origin, structure, & future of the universe.
Measuring red shift --- Hubble found that the spectra of most galaxies shifted toward the red end; examining the amount of red shift can determine the speed the galaxies are moving away from Earth.
From this determined the universe is expanding

3. Big Bang Theory
Billions of years ago all the matter in the universe was compacted into one small volume
About 14 billion years ago, all of this matter exploded outward in all directions in an event called the big bang
The cloud of matter expanded and parts of it began to clump together and formed galaxies.
The universe has continued to expand

4. Evidence for the Big Bang Theory
Background Radiation: Throughout the universe low level energy is distributed evenly. Formed shortly after the Big Bang
Ripples --- These are irregularities in the cosmic background radiation; caused by small fluctuations in the distribution of matter in the early universe; the ripples might also indicate the 1st stages in the formation of the universe’s 1st galaxy.

5. Darkness
Dark Matter – Matter in the universe that doesn’t give off light but has detectable gravity.
Dark Energy – Most of the universe is made up of something we know nothing about; acts as a force that opposes gravity.