1. Stars

2. Life on other planets video • NOVA “Alien planets” video • http://www.pbs.org/wgbh/nova/space/alien-planets-revealed.html

3. Types of spectra • Emission

4. Types of spectra • Absorption

5. Types of spectra • Continuous

6. Use of spectra • Scientist use spectra to determine what elements are in a star. • The elements in the star determine its temperature and age. • Stars produce dark line spectra. • Elements absorb certain wavelengths of light.

7. Use of spectra

8. Star classification

9. HR diagram use • From the following animation, we are going to look at the life cycle of a star like our sun. We will explain step by step what happens as it changes. • http://lcogt.net/files/flash/hr-diagram/main.html

10. Our Sun’s life cycle

11. Stellar life cycle

12. Life cycle assignment • Use the drawing on the previous page to describe, in 3 paragraphs, the life cycle of small, medium, and large stars. • Must state what happens to move from one stage to the next. • Include a copy of the sketch.

13. Life and death of stars video • https://www.youtube.com/watch?v=ng0WMRCq3wU

14. Groups of stars • Binary stars—a pair of stars bound by gravity to each other. • Clusters—may contain up to 100,000 stars in a group.

15. Groups of stars • Galaxies—large groups of stars held together by gravity. • The Milky way galaxy is about 100,000 light years across and has more than 200,000,000,000 stars. • Distances to galaxies are determined using Cepheid variables, which are stars that change size.

16. Shapes of Galaxies • Spiral

17. Shapes of Galaxies • Spiral

18. Shapes of Galaxies • Barred Spiral

19. Shapes of Galaxies • Barred Spiral

20. Shapes of Galaxies Elliptical

21. Shapes of Galaxies Irregular

22. Shapes of Galaxies Irregular

23. Shapes of Galaxies

24. Shapes of Galaxies

25. Big bang theory • States that all matter used to be compressed into one tiny place. • An unidentified force caused it to explode outward. • Future fate is unknown. • Could continue expanding, stop, or stop and return inward.

26. Big bang theory • Cosmic background radiation is found throughout the universe. • Assumed to be caused by big bang. • Dark matter and dark energy have been assumed to make up a vast majority of the universe because expansion models don’t work without it.

27. Big bang theory • This theory may be changed in the future or even replaced as something else comes along. • Remember, a theory is a possible explanation, not a fact!

28. The end of the universe • https://www.youtube.com/watch?v=4-PR6ms7_GU