1. Objective 04/12/2013
Identify three types of galaxies.
Intro
Do all galaxies come in the same shape or size as our galaxy?
DO NOW
Check and Hand in Missing Assignments
Take out Weekly WS #30 & Agenda

2. Galaxies

3. galaxy
a collection of stars, dust, and gas held together by gravity
Can contain billions of stars
There are billions of galaxies in the universe

4. have a bulge at the center and spiral arms.
Spiral Galaxies
have a bulge at the center and spiral arms.
The Milky Way

7. Elliptical Galaxies
A massive blob of stars
Very bright centers but little dust and gas

9. Irregular Galaxies
Galaxies that don’t fit into any other class
“leftovers”

11. Contents of Galaxies Stars Nebulae Star clusters What’s in a galaxy?
Planets
Nebulae
Star clusters

14. Objective: 12 April 2013
Identify three types of galaxies.
Outro
Where are we located in our galaxy?