1. Aim: How did the universe form?
Do Now: List in order from smallest to largest: our Sun, the Milky Way Galaxy, Universe, Earth

2. Explain how it all began?

3. How did the universe begin?
Big Bang – a powerful explosion of a very dense mass about billion years ago that produced the expanding universe that exists today
How the Universe Formed Space exploration may provide clues as to how the universe was formed. Scientists think that the entire universe was once contained in a single, very hot, very dense point. Between 15 and 20 billion years ago, a huge explosion caused it to start expanding rapidly. This explosion is called the Big Bang.
As the universe expanded, it cooled. Atoms and molecules formed. Gradually, the atoms and molecules collected into the objects that make up today’s universe, which is still expanding today.
First elements in space were hydrogen and helium.
----- Meeting Notes (9/13/16 09:19) -----

4. How do scientists know the universe is expanding?
Evidence for the Big Bang:
Cosmic background radiation: radiation coming from all directions in the universe
Doppler Effect: a change in light or sound wavelengths as a source moves towards or away for an observer. (Hubble's Law)
Light radiating from distant galaxies are measured on the visible spectrum
Red shift
Objects moving away from you
Longer wavelengths (stretched)
Blue shift
Objects moving towards you
Shorter wavelengths (squeezed)

5. How do we define galaxy? How are these galaxies different?
Galaxy: a collection of billions of stars, gas and dust held together by gravity.
Galaxies Stars appear as small point of light. Among these points of light, you can also see some fuzzy patches. Some of these patches are nebulae, or clouds of gas and dust. Others are galaxies. A galaxy is a huge collection of stars, gas, and dust that travel together through space. Using the newest telescopes, astronomers can see billions of galaxies. Galaxies are the building blocks of the universe.
Galaxies have different shapes. Astronomers classify, or group, galaxies based on shape. There are three kinds of galaxies: elliptical, irregular, and spiral.
How are these galaxies different?
Galaxies classified based on shape
Spiral – shaped like pinwheels with huge spiral arms
Elliptical – circular or slightly flatten
Irregular – no regular shape

6. How would your describe our galaxy?
Milky Way Galaxy: spiral galaxy; our solar system (sun) is located in the arm about two-thirds the distance away from the center of the galaxy
Andromeda Galaxy – spiral galaxy, 2.2 million light years away
Light Year - the distance light travels in one year – about 6 trillion miles (9.5 trillion kilometers)
100,000 Light Years
2/3 down arm
Arms
Center Bulge (Nucleus)

7. Infer a possible fate for our universe?
Big Crunch - Universe is going to stop expanding and all of matter will eventually cluster together again.
Indefinite Expansion - Universe is going to continue to expanding forever and ever. All the stars will eventually burn out of fuel.
Big Rip - Universe will expand so fast that all of matter will literally “rip” and nothing will exist

8. How are the following two solar systems different?
Which Solar System do we have today? Why?
How are the following two solar systems different?
Picture A
Picture B
Geocentric model
Earth centered
Heliocentric model Sun centered

9. Summary Activity Solar System Galaxies Universe Sun
How can you arrange the following shapes to represent the entire universe?
Solar System
Galaxies
Universe
Sun

10. Extra Questions

11. Extra Questions