2. The Life Cycle of Stars

3. “protostar”

4. The Life Cycle of Stars “protostar” “Main Sequence” (longest phase in a star’s cycle

5. The Life Cycle of Stars “protostar” “Main Sequence” “Red Giant”

6. The Life Cycle of Stars “protostar” “Main Sequence” “Red Giant” “White Dwarf”

7. The Life Cycle of Stars “protostar” “Main Sequence” “Red Giant” “White Dwarf” Cycle for Massive Star: Nebula Main Sequence Super Red Giant Neutron Star, Pulsar, or Black Hole forms at end of its life cycle

8. Star Phases: Charted on H-R Diagram

9. Explaining the H-R Diagram “H” = Hertzsprung “R” = Russell graph of temperature and brightness of all stars

10. A Closer Look at the H-R Diagram

11. Star Phases: Charted on H-R Diagram The H-R Diagram shows the relationship between absolute magnitude, luminosity, classification, and effective temperatures of stars. The H-R Diagram can be used to define different types of stars.

12. Explaining the H-R Diagram Temperature: horizontal (bottom) axis. hotter at left cooler toward right

13. Explaining the H-R Diagram Brightness: vertical (left side) axis. brightest stars near top dim stars near bottom

14. Explaining the H-R Diagram A star’s position on the diagram will change as it moves from its “birth” to its “death”.

15. Explaining the H-R Diagram YouTube Style

16. Your Turn to Practice Get a copy of HR Diagram. Color the different sections of the HR Diagram using colored pencils. Answer questions 1- 15 using your notes and textbook.