1. Chapters 12 and 13 The Sun & Measuring the Properties of Stars

2. “We are star stuff” - Carl Sagan

3. Reminder... star: A self-luminous, gravitationally bound, ball of gas that shines or has shone because of nuclear reaction in its interior

4. Brown Dwarfs- Failed Stars Mass < 8% the mass of the Sun And 10-80 times the mass of Jupiter First detected in 1995

5. The Sun and other stars are huge and massive!!!

6. Figure 11.1 Our Sun

7. Sunspots regions of the photosphere that are dark and relatively cool corresponds to regions of intense magnetic fields Galileo monitored their movement to determine the rotation period of the Sun= about 1 month

8. Figure 11.16 Sunspots occur when the magnetic field loops out of the photosphere

9. Figure 11.18a Prominences Filaments

10. Flares and Coronal Mass Ejections coronal mass ejections flares

11. The Earth’s magnetic field protects us!

12. Sunspot Cycle Maximum number Minimum number

13. Figure 11.23 Sun’s Rotation

14. Babcock’s Magnetic Dynamo Theory

15. Binary Stars binary stars: multiple systems bound by gravity and orbiting each other around their center of mass (double star)

16. Contact Binary Stars

17. Star Clusters Open ClusterGlobular Cluster

18. Open or Globular Cluster?