2. Galaxies and Beyond

3. Where are we in the universe? Southwest middle is in the USA The USA is on planet Earth Planet Earth is in the Solar System The solar system is in the Milky Way Galaxy The Milky Way Galaxy is in the local group of galaxies

4. The Universe is REALLY big! The local group is just one tiny group of galaxies in space.

5. So, what is a galaxy? A galaxy is a giant group of billions of stars.stars Our Sun is one of billions of stars in a galaxy called the Milky WaySunMilky Way

6. Milky Way is only one of billions of galaxies in the Universe.Universe

7. A new unit for distance The Milky way contains about 200 billion stars. Kilometers and miles are too small a unit for space. The distance between galaxies and stars is measured in light years

8. How big is a light year? A light year is the distance light travels in a year. 1 light year= 9.46 x 10 12 kilometers

9. Our Sun is located in one of the spiral arms, called the Orion arm It is about 30,000 light years from the galactic center It orbits every 200 million years.

10. Think pair share A & C ask: What is a galaxy? A & C ask: What is a galaxy? B & D ask: What galaxy do we live in? B & D ask: What galaxy do we live in? A & C ask: What unit do you use to measure galaxies? A & C ask: What unit do you use to measure galaxies? B & D ask: Where is the sun? B & D ask: Where is the sun?

11. Types of galaxies SpiralEllipticalIrregular

12. The Milky Way and most of its neighbors are spiral (although irregular galaxies are actually the most common).

13. Elliptical Galaxies Elliptical galaxies are simply vast collections of stars that remain relatively close together because of the gravitational attraction between them.

14. Irregular Galaxies Irregular galaxies can have any shape. There are two types of irregular galaxy: Type I's and Type II’s

15. Type I These are single galaxies that have a strange shape

16. Type II Type II irregular galaxies are made when two galaxies collide

17. White Board Time! 9 questions

18. Name that galaxy

21. 4. What are galaxies? 4. What are galaxies? Clusters of billions of stars Clusters of billions of stars 5. What are some different types of galaxies? 5. What are some different types of galaxies? Spiral, elliptical, irregular Spiral, elliptical, irregular 6. How do we measure their size? 6. How do we measure their size? In light years In light years 7. What is the name of our galaxy? 7. What is the name of our galaxy? Milky way Milky way 8. What type of galaxy is it? 8. What type of galaxy is it? spiral spiral 9. Is our sun at the center? 9. Is our sun at the center? No! No!