Sun, Moon, Earth,

1. What kind of life cycle does a star have? Sun, Moon, Earth,

2. Star “Birth”:

3. Star “Birth”: • All stars start out as part of a Nebula.

4. Star “Birth”: • All stars start out as part of a Nebula. • Nebula: A large cloud of gas and dust spread out over an immense volume.

5. Star “Birth”: • In the densest part of a Nebula gravity begins pulling the gas and dust together.

6. Star “Birth”: • In the densest part of a Nebula gravity begins pulling the gas and dust together. • A Protostaris formed when there is enough mass (gas and dust) concentrated to form a star.

7. Star “Birth”: • As gravity continues to shrink the protostar it reaches a point where it is close to the size it will be. At this point it is called a T Tauri star.

8. Star “Birth”: • Once the gas and dust become so dense and hot (about 15 million °K) that nuclear fusion starts the star is “born”.

9. Star “Birth”: • Once the gas and dust become so dense and hot (about 15 million °K) that nuclear fusion starts the star is “born”. • This process can take from 60,000 to 150 million years.

10. Star Fact: • With all of the nuclear fusion happening why doesn’t the star “blow up”?

11. Star Fact: • With all of the nuclear fusion happening why doesn’t the star “blow up”? • Stars have a gravitational equilibriumwhich means gravity pulling in and nuclear fusion pushing out are exactly balanced.

12. Star “Life”: • How long a star lives depends on its mass (how much fuel it has to burn up).

13. Star “Life”: • How long a star lives depends on its mass (how much fuel it has to burn up). • Large mass stars live the shortest.

14. Star “Life”: • How long a star lives depends on its mass (how much fuel it has to burn up). • Large mass stars live the shortest. • Low mass stars live the longest.

15. Star “Life”:

16. Star “Death”: • When a star runs out of “fuel” it begins to die.

17. Star “Death”: • When a star runs out of “fuel” it begins to die. • Once this happens the star will become one of three things.

18. Star “Death”: • When a star runs out of “fuel” it begins to die. • Once this happens the star will become one of three things. • White dwarf

19. Star “Death”: • When a star runs out of “fuel” it begins to die. • Once this happens the star will become one of three things. • White dwarf • Neutron star

20. Star “Death”: • When a star runs out of “fuel” it begins to die. • Once this happens the star will become one of three things. • White dwarf • Neutron star • Black hole

21. Star “Death”: • Low to medium mass stars (A-M)

22. Star “Death”: • Low to medium mass stars (A-M) • As a star runs out of fuel its outer layers expand.

23. Star “Death”: • Low to medium mass stars (A-M) • As a star runs out of fuel its outer layers expand. • Becomes a Red Giant.

24. Star “Death”: • Low to medium mass stars (A-M) • As a star runs out of fuel its outer layers expand. • Becomes a Red Giant. • Outer layers are “ejected” from the star’s core as a Planetary Nebula.

25. Star “Death”: • Low to medium mass stars (A-M) • As a star runs out of fuel its outer layers expand. • Becomes a Red Giant. • Outer layers are “ejected” from the star’s core as a Planetary Nebula. • The core that is left behind cools and becomes aWhite Dwarf.

26. Star “Death”: • Low to medium mass stars (A-M) • As a star runs out of fuel its outer layers expand. • Becomes a Red Giant. • Outer layers are “ejected” from the star’s core as a Planetary Nebula. • The core that is left behind cools and becomes aWhite Dwarf. • Glows because it is still really hot.

27. Star “Death”: • Low to medium mass stars (A-M) • As a star runs out of fuel its outer layers expand. • Becomes a Red Giant. • Outer layers are “ejected” from the star’s core as a Planetary Nebula. • The core that is left behind cools and becomes aWhite Dwarf. • Glows because it is still really hot. • After it finishes cooling it becomes aBlack Dwarf.

28. Star “Death”: • High mass stars (O and B)

29. Star “Death”: • High mass stars (O and B) • Same as small mass up to Red Giant phase.

30. Star “Death”: • High mass stars (O and B) • Same as small mass up to Red Giant phase. • Fusion continues up to Iron (Fe).

31. Star “Death”: • High mass stars (O and B) • Same as small mass up to Red Giant phase. • Fusion continues up to Iron (Fe). • Iron absorbs energy but doesn’t go through fusion.

32. Star “Death”: • High mass stars (O and B) • Same as small mass up to Red Giant phase. • Fusion continues up to Iron (Fe). • Iron absorbs energy but doesn’t go through fusion. • Releases the energy in a massive explosion as aSupernova.

33. Star “Death”: • High mass stars (O and B) • Same as small mass up to Red Giant phase. • Fusion continues up to Iron (Fe). • Iron absorbs energy but doesn’t go through fusion. • Releases the energy in a massive explosion as aSupernova. • Form one of two things.

34. Star “Death”: • High mass stars (O and B)

35. Star “Death”: • High mass stars (O and B) • Neutron Stars: Forms from the remains of the old star.

36. Star “Death”: • High mass stars (O and B) • Neutron Stars: Forms from the remains of the old star. • Very very high density and very very small.

37. Star “Death”: • High mass stars (O and B) • Neutron Stars: Forms from the remains of the old star. • Very very high density and very very small. • As much as three times the mass of our star in an area the size of a city.

38. Star “Death”: • High mass stars (O and B) • Neutron Stars: Forms from the remains of the old star. • Very very high density and very very small. • As much as three times the mass of our star in an area the size of a city. • Some give off regular pulses of radio waves and are called pulsars.(these were originally called LGMs).

39. Star “Death”: • High mass stars (O and B)

40. Star “Death”: • High mass stars (O and B) • Black Holes: “Objects” in space that have such high gravity that nothing (not even light) can escape them.

41. Star “Death”: • High mass stars (O and B) • Black Holes: “Objects” in space that have such high gravity that nothing (not even light) can escape them. • We can find them because….

42. Star “Death”: • High mass stars (O and B) • Black Holes: “Objects” in space that have such high gravity that nothing (not even light) can escape them. • We can find them because…. • Stars that are close to them are “pulled” by the gravity of the black hole.

43. Star “Death”: • High mass stars (O and B) • Black Holes: “Objects” in space that have such high gravity that nothing (not even light) can escape them. • We can find them because…. • Stars that are close to them are “pulled” by the gravity of the black hole. • Gases in the area are pulled in so fast (like a drain in a sink) that they spin around the black hole and we see the heat given off.

44. Where are we in the big picture? Sun, Moon, Earth,

45. Our cosmic address: • Some numbers you need to know:

46. Our cosmic address: • Some numbers you need to know: • Light year =

47. Our cosmic address: • Some numbers you need to know: • Light year =9,439,922,663,400 km

48. Our cosmic address: • Some numbers you need to know: • Light year =9,439,922,663,400 km • AU = Astronomical Unit

49. Our cosmic address: • Some numbers you need to know: • Light year =9,460,730,472,581 km • AU = Astronomical Unit • Average distance from the Earth to the sun

50. Our cosmic address: • Some numbers you need to know: • Light year =9,460,730,472,581 km • AU = Astronomical Unit • Average distance from the Earth to the sun • 1 AU =