1. Stars The life and death of stars in our universe

2. What are stars? A massive ball of plasma and gas fueled by nuclear fusion: Hydrogen  Helium  Carbon  …

3. What are stars? Astronomers learn about stars using the star’s luminosity, color, and motion through space Luminosity = energy/time Color = light waves emitted from the star (depicts what elements the star is made of).

4. How are Stars Made? 1.Protostar – A large cloud of dust and particles that begins to contract on itself

5. How are Stars Made? 2.Main Sequence – A star will fall on the main sequence, depending on its temperature and luminosity.

7. Life Cycle of a Star

8. But First… Let’s Get Some Perspective…

14. The Known Universe

15. How are Stars Made? Yellow Star  Red Giant High luminosity “Smaller” in size

16. How are Stars Made? Red Giants Core gets extremely hot and collapses in on itself, while the outer layers expand

17. How are Stars Made? Red Giants  Planetary Nebula Red Giants continue to eject its outer layers. Planetary Nebula is an expanding, glowing shell of ionized gas

18. How are Stars Made? Planetary Nebula  White Dwarfs The star continues to eject its outer layers until the core is exposed. The core is dead, but still very hot. This core is called a White Dwarf.

19. How are Stars Made? White Dwarfs White Dwarfs may become Novae

20. Life Cycle of a Star

21. How are Stars Made? Blue Star  Red Supergiant High luminosity Large in size

22. How are Stars Made? Red Supergiant High luminosity Core gets extremely hot and collapses in on itself, while the outer layers expand

23. How Are Stars Made? Red Supergiant  Supernova Red Supergiants run out of fuel (energy) and the core collapses This results in a giant explosion

24. How Are Stars Made? Supernova  Neutron Star The supernova core becomes more dense as it continues to collapse - fusing protons and electrons into neutrons

25. How are Stars Made? Neutron Star  Black Hole Eventually, the neutron star’s core collapses completely Black hole = an infinitely dense object whose gravity is so strong, nothing can escape it’s immediate proximity (not even light)