Download to read offline
nucleosynthesis-100203170292hpapp01.pptx
- 1.
- 2.
- 3. Our universe startedwith a BIG BANG.
- 4. big bang n.(cosmology) the cosmic explosion that is hypothesized to have marked the origin of the universe.
- 5. After the BIGBANG, the universe started to expand.
- 6. The first secondsafter the BIG BANG, it was very hot.
- 7. Then, the universe startedto cool down.
- 8. Right after theBIG BANG, the p+, the n0 and the e- were flying around without control.
- 9. When it startedto cool down, the quarks started making primitive elements:
- 10.
- 11. 1 2 Hydrogen, 1 proton,1 neutron
- 12. 2 3 Helium, 2 protons,1 neuron
- 13. 2 4 Helium, 2 protons,2 neurons
- 14.
- 15. Star n. aself-luminous gaseous spherical celestial body of great mass which produces energy by means of nuclear fusion reactions .
- 16. In the stars,because of high pressure, the elements started bonding and forming heavier elements
- 17. HOW WILL WEEND?
- 18. We all startedwith the BIG BANG…
- 19. … but howwill we end?
- 20. Some scientists aresure that the universe will continue to expand forever.
- 21. However, there isa theory that our universe will end in “big crunch”
- 22. It states thatsomeday the universe will stop expanding and crunch together.
- 23. There is noproof for that theory.
- 24. . . . . . . . . . . . . . . . . . . Clas .sifying Stars . . . . . .
- 25. TO RECOGNISE STARS, SCIENTISTSHAVE TO CLASSIFY THEM
- 26.
- 27.
- 28.
- 29.
- 30.
- 31. If the staris blue, it means it is very hot . (≈50,000 C°)
- 32. . . . . . . . . . ..... .. .... . . .... ....... . . ... Cold stars are red.
- 33. The bigger or hotterthe star is, the brighter it is.
- 34. Brightness is measuredin 2 ways:
- 35. apparent brightness (brightness seenfrom earth)
- 36. absolute brightness (the“real” brightness of the star)
- 37. Stars are mostlymade out of hydrogen.
- 38. Helium is about¼ of the stars’ composition.
- 39. Enjar Hertzsprung andHenry Norris Russell made a diagram that classifies stars.
- 40.
- 41. Scientists measure distance between starsusing parallax
- 42. Parallax n. apparentchange in apposition of an object when you look at it from different places
- 43. Scientists watch thepositions of stars during different times of the year to figure out it’s position.
- 44.
- 45. Stars do not liveforever.
- 46. The larger a staris, the shorter its life is.
- 47. Stars are bornin nebulas.
- 48. Nebula n. alarge cloud of dust in space
- 49. Gravity pulls dusttogether so it forms a protostar
- 50. Protostar n. anearly stage in the evolution of a star, after the beginning of the collapse of the gas cloud from which it is formed, but before sufficient contraction has occurred to permit initiation of nuclear reactions at its core.
- 51. As the protostargets denser and denser, it forms a star
- 52. as the starbecomes older, it becomes a red giant
- 53. red giant= staruses up its energy and becomes cooler, so it expands
- 54. Layers of thered giant fall off, releasing dust and gas into space.
- 55. It is calleda planetary nebula.
- 56. The remaining star isvery dense and bright.
- 57. It is awhite dwarf.
- 58. When a white dwarfstops glowing, it is called a black dwarf.
- 59. high-mass stars aredifferent.
- 60. When they die,they make a supernova – a giant explosion.
- 61. After the supernova, thestar becomes either a neutron star or a black hole.
- 62. a neutron star:a white dwarf that has very high pressure and temperature
- 63. A black holeis a neutron star with gravity so strong that nothing, even light, can escape.
- 64.
- 65. Nucleosynthesis is been studiedby physicists and astronomers.
- 66.
- 67.