What do we need for life like us?

1. What do we need for life like us? planet star What is a star needed for? energy

2. Solar Energy plants solar energy used to make complex molecules food animals eat plants for energy wood solar energy stored in chemical form fossil fuels coal oil nat gas plants and animals hydroelectric sun lifts water wind sun drives wind

3. Solar Energy nuclear fission uranium underground supernova geothermal Iceland Calistoga geysers planet tidal high tide fills bay low tide empties moon What doesn’t come from our environment?

4. temperature/speed average speed some slower some faster some much faster temperature bombardment pressure blown

5. 1H 2H 3H 4He 3He Ionized Isotopes

6. + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +

7. Nuclear Forces repulsive attractive weak strong long range close range

8. + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +

9. E=mC2 e+ e- + Proton-Proton Chain n + 1H 1H 2H e+ + + mass charge proton high + neutron high 0 electron low - positron low + matter anti-matter annihilation matter → energy

10. + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +

11. n + 6 sec g + + 2H 1H 3He Proton-Proton Chain + 1H 1H 2H e+ + g + + 2H 1H 3He

12. n + + 1H 1H Proton-Proton Chain + 1H 1H 2H e+ + g + + 2H 1H 3He + 3He 3He + 4He

13. Radiation Conduction Convection Transparent Contact & Good Conductor Fluid or Gas Energy Transport What conditions are required?

14. Random Walk

16. Star Forming Region

17. Star Forming Region

18. Star Forming Region

19. Star Forming Region

20. Star Forming Region

21. Star Forming Region

22. Star Forming Region

23. Star Forming Region

24. Star Forming Region

25. Star Forming Region

26. Star Forming Region

27. Protostars

28. Protostars

29. Protostars

30. Gas Cocoon Protostar

31. Lost Potential Energy Gaining Kinetic Energy Gaining Speed Gas Cocoon Gas Rising Temperature Gravity pulls inward. Some other force pushes out. Gas pressure pushes outward. Stops Collapse

32. Cocoon Where is the temperature highest?

33. Radiation Cools Protostar Heats Cocoon Escape Velocity? Convection

34. Cools Protostar Heats Cocoon Escape Velocity?

35. Cools Protostar Heats Cocoon Escape Velocity? Protostar Collapse

36. Stellar Wind Sheds Outer Layer Mass Loss

37. Stellar Wind Sheds Outer Layer Mass Loss

38. Stellar Wind Sheds Outer Layer Mass Loss Collapse Continues

40. Convection? Core Energy Transport Slows

41. Core Fusion H He

42. g n e+ + g CNO Cycle + + 1H 13N 12C + 13N 13C + 13C 1H + 14N

43. g n e+ + CNO Cycle + 14N + 1H 15O 15O + 15N 15N + 4He 1H 12C +

45. Stellar Wind Cocoon Gone Star Exposed

46. First star disrupts later stars.

49. n + + 1H 1H Proton-Proton Chain + 1H 1H 2H e+ + g + + 2H 1H 3He + 3He 3He + 4He

50. Long Main Sequence Life Millions of Years for Some Billions of Years for Others Mostly Stable Energy Output Mostly Stable Size Gradual Increase in Both Core H He