1. Star Groups Chapter 27 (p. 561-565)

2. Galaxies Def: large groups of stars (approx. 100 billion) bound by gravitational attraction Also contain gas and dust clouds (nebulae) Nearest Galaxies –Large Magellanic Cloud (LMC) (150 m.l.y.)

3. LMC

4. SMC

5. Types of Galaxies Spiral- outstretched curving arms

6. M100

7. NGC 3370

8. Barred spiral Like a spiral but has a bar going through the center

9. NCG 6946

11. Elliptical galaxies Round to oblong in shape

12. NCG 4565

13. M104 (The Sombrero Galaxy)

14. M-81 (Andromeda Galaxy)

15. NCG 4636

16. NGC 720

17. Irregular No specific shape No symmetry

18. NCG 1705

19. G1- Globular Cluster

20. Omega-Centauri

21. M 80 Globular Cluster

22. NCG 6822

23. Our Milky Way

24. Milky Way Structure Barred spiral galaxy About 100,000 light- years wide Sun is 30,000 light-years from the center Rotates every 200 million years around “galactic center”

25. Milky Way

26. Face-on view of the Milk Way Galaxy

27. Edge-on view of the Milk Way Galaxy

28. Is the center of every galaxy a supermassive black hole?

29. M105 NGC 3384

30. Hubble deep field

31. Merger of two Spirals to form an Elliptical

32. Colliding galaxies movie http://wps.prenhall.com/wps/media/objects/ 680/696364/ifa_colliding_galaxies.mpghttp://wps.prenhall.com/wps/media/objects/ 680/696364/ifa_colliding_galaxies.mpg

33. Local group Local Group Milky way and nearest galaxies Contains at least 28 galaxies

34. LARGEST TO SMALLEST UNIVERSE LOCAL GROUPS GALAXIES SOLAR SYTEMS

35. Power of Ten http://micro.magnet.fsu.edu/primer/java/scie nceopticsu/powersof10/index.htmlhttp://micro.magnet.fsu.edu/primer/java/scie nceopticsu/powersof10/index.html

36. Galaxy Song from Monty Python http://www.youtube.com/watch?v=mEY6Y ojnex0&feature=related&safety_mode=true &persist_safety_mode=1http://www.youtube.com/watch?v=mEY6Y ojnex0&feature=related&safety_mode=true &persist_safety_mode=1