full transcript

From the Ted Talk by Dennis Wildfogel: What is the universe made of?

Unscramble the Blue Letters

All the material objects around you are composed of sucmoioipbcrsc units we call molecules. And molecules in turn are cosmeopd of individual aomts. Molecules feulntqery break apart and then form new molecules. On the other hand, virtually all the atoms you come in to contact with through the course of your life, the ones in the ground beneath you, the air you breath, the food you eat, those that make up every living thing, including you, have existed for billions of years and were created in places very unlike our planet. How those atoms came about is what I want to srhae with you. It all started 14 billion years ago with an event we call The Big Bang, which resulted in a universe consisting of gas alone. There were no stars and no planets. The gas was made up only of atoms bniegnolg to the simplest elements. It was about 75 percent hgredoyn and almost all the rest was helium. No eteelmns like carbon, oxygen or nitrogen existed. No iron, silver or gold. In some places, the density of this gas was slightly higher than in others. Due to gravity, those paecls attracted even more gas, which further strengthened the pull of gravity, which then drew more gas in, and so on. Eventually, large dense gas balls formed, shrinking under their own gravity and consequently heating up on the inside. At some point, the core of such a ball gets hot enough that nuclear fusion occurs. Hydrogen atoms samsh together to form helium, accompanied by a great rlesaee of eergny, strong enough to counteract the shrinking fcore of the gravity. When the energy pushing out from the fusion rctinoeas matches the gravity pulling all the gas inwards, an equilibrium occurs. From this a star is born. Over its lifetime, the fusion reactions in the core of a massive star will produce not only helium, but also carbon, oyxegn, nitrogen and all the other elements in the piioerdc table up to iron. But etavenully, the core's fuel runs out, laniveg it to coslpale completely. That causes an ulbaneiebvly powerful explosion we call a supernova. Now there are two things to note about how supernovas create elements. First, this explosion raeslees so much energy that fsouin goes wild fnoirmg elements with atoms even heavier than iron like silver, gold and uranium. Second, all the elements that had been accumulating in the core of the star, like carbon, oxygen, nitrogen, iron, as well as all of those formed in the supernova explosion, are ejected in to interstellar spcae where they mix with the gas that's already there. History then repeats itself. Gas clouds, now containing many elements besides the original hydrogen and helium, have higher density areas that acatrtt more matter, and so on. As before, new stars result. Our sun was born this way about 5 billion years ago. That means that the gas it arose from had itself been enriched with many elements from sepnruvoa explosions since the unisevre began. So that's how the sun wound up with all the elements. It's still mostly hydrogen at 71 percent, with most of the rest being heluim at 27 percent. But bear in mind that while the first stars were made up of hydrogen and helium alone, the remaining elements in the periodic table make up two percent of the sun. And what about erath? Planets form as an incidental process to star formation out of the same gas cloud as the star itself. salml planets like ours don't have enough gravity to hold on to much hydrogen or helium gas since both of those are very light. So, even though carbon, ngoitren, oxygen and so on made up only two percent of the gas cloud from which Earth was formed, these heavier elements form the bulk of our plnaet and everything on it. Think about this: with the exception of hydrogen and some helium, the ground you walk on, the air you breath, you, everything is made of atoms that were cearted inside srats. When scientists first wkroed this out over the first half of the 20th Century, the famous astronomer Harlow Shapley commented, "We are brothers of the boulders, consuis of the clouds."

Open Cloze

All the material objects around you are composed of ______________ units we call molecules. And molecules in turn are ________ of individual _____. Molecules __________ break apart and then form new molecules. On the other hand, virtually all the atoms you come in to contact with through the course of your life, the ones in the ground beneath you, the air you breath, the food you eat, those that make up every living thing, including you, have existed for billions of years and were created in places very unlike our planet. How those atoms came about is what I want to _____ with you. It all started 14 billion years ago with an event we call The Big Bang, which resulted in a universe consisting of gas alone. There were no stars and no planets. The gas was made up only of atoms _________ to the simplest elements. It was about 75 percent ________ and almost all the rest was helium. No ________ like carbon, oxygen or nitrogen existed. No iron, silver or gold. In some places, the density of this gas was slightly higher than in others. Due to gravity, those ______ attracted even more gas, which further strengthened the pull of gravity, which then drew more gas in, and so on. Eventually, large dense gas balls formed, shrinking under their own gravity and consequently heating up on the inside. At some point, the core of such a ball gets hot enough that nuclear fusion occurs. Hydrogen atoms _____ together to form helium, accompanied by a great _______ of ______, strong enough to counteract the shrinking _____ of the gravity. When the energy pushing out from the fusion _________ matches the gravity pulling all the gas inwards, an equilibrium occurs. From this a star is born. Over its lifetime, the fusion reactions in the core of a massive star will produce not only helium, but also carbon, ______, nitrogen and all the other elements in the ________ table up to iron. But __________, the core's fuel runs out, _______ it to ________ completely. That causes an ____________ powerful explosion we call a supernova. Now there are two things to note about how supernovas create elements. First, this explosion ________ so much energy that ______ goes wild _______ elements with atoms even heavier than iron like silver, gold and uranium. Second, all the elements that had been accumulating in the core of the star, like carbon, oxygen, nitrogen, iron, as well as all of those formed in the supernova explosion, are ejected in to interstellar _____ where they mix with the gas that's already there. History then repeats itself. Gas clouds, now containing many elements besides the original hydrogen and helium, have higher density areas that _______ more matter, and so on. As before, new stars result. Our sun was born this way about 5 billion years ago. That means that the gas it arose from had itself been enriched with many elements from _________ explosions since the ________ began. So that's how the sun wound up with all the elements. It's still mostly hydrogen at 71 percent, with most of the rest being ______ at 27 percent. But bear in mind that while the first stars were made up of hydrogen and helium alone, the remaining elements in the periodic table make up two percent of the sun. And what about _____? Planets form as an incidental process to star formation out of the same gas cloud as the star itself. _____ planets like ours don't have enough gravity to hold on to much hydrogen or helium gas since both of those are very light. So, even though carbon, ________, oxygen and so on made up only two percent of the gas cloud from which Earth was formed, these heavier elements form the bulk of our ______ and everything on it. Think about this: with the exception of hydrogen and some helium, the ground you walk on, the air you breath, you, everything is made of atoms that were _______ inside _____. When scientists first ______ this out over the first half of the 20th Century, the famous astronomer Harlow Shapley commented, "We are brothers of the boulders, _______ of the clouds."

Solution

  1. space
  2. leaving
  3. release
  4. releases
  5. belonging
  6. cousins
  7. attract
  8. unbelievably
  9. reactions
  10. force
  11. fusion
  12. energy
  13. earth
  14. share
  15. submicroscopic
  16. smash
  17. helium
  18. periodic
  19. places
  20. collapse
  21. hydrogen
  22. planet
  23. small
  24. worked
  25. supernova
  26. oxygen
  27. atoms
  28. composed
  29. universe
  30. eventually
  31. stars
  32. elements
  33. forming
  34. nitrogen
  35. frequently
  36. created

Original Text

All the material objects around you are composed of submicroscopic units we call molecules. And molecules in turn are composed of individual atoms. Molecules frequently break apart and then form new molecules. On the other hand, virtually all the atoms you come in to contact with through the course of your life, the ones in the ground beneath you, the air you breath, the food you eat, those that make up every living thing, including you, have existed for billions of years and were created in places very unlike our planet. How those atoms came about is what I want to share with you. It all started 14 billion years ago with an event we call The Big Bang, which resulted in a universe consisting of gas alone. There were no stars and no planets. The gas was made up only of atoms belonging to the simplest elements. It was about 75 percent hydrogen and almost all the rest was helium. No elements like carbon, oxygen or nitrogen existed. No iron, silver or gold. In some places, the density of this gas was slightly higher than in others. Due to gravity, those places attracted even more gas, which further strengthened the pull of gravity, which then drew more gas in, and so on. Eventually, large dense gas balls formed, shrinking under their own gravity and consequently heating up on the inside. At some point, the core of such a ball gets hot enough that nuclear fusion occurs. Hydrogen atoms smash together to form helium, accompanied by a great release of energy, strong enough to counteract the shrinking force of the gravity. When the energy pushing out from the fusion reactions matches the gravity pulling all the gas inwards, an equilibrium occurs. From this a star is born. Over its lifetime, the fusion reactions in the core of a massive star will produce not only helium, but also carbon, oxygen, nitrogen and all the other elements in the periodic table up to iron. But eventually, the core's fuel runs out, leaving it to collapse completely. That causes an unbelievably powerful explosion we call a supernova. Now there are two things to note about how supernovas create elements. First, this explosion releases so much energy that fusion goes wild forming elements with atoms even heavier than iron like silver, gold and uranium. Second, all the elements that had been accumulating in the core of the star, like carbon, oxygen, nitrogen, iron, as well as all of those formed in the supernova explosion, are ejected in to interstellar space where they mix with the gas that's already there. History then repeats itself. Gas clouds, now containing many elements besides the original hydrogen and helium, have higher density areas that attract more matter, and so on. As before, new stars result. Our sun was born this way about 5 billion years ago. That means that the gas it arose from had itself been enriched with many elements from supernova explosions since the universe began. So that's how the sun wound up with all the elements. It's still mostly hydrogen at 71 percent, with most of the rest being helium at 27 percent. But bear in mind that while the first stars were made up of hydrogen and helium alone, the remaining elements in the periodic table make up two percent of the sun. And what about Earth? Planets form as an incidental process to star formation out of the same gas cloud as the star itself. Small planets like ours don't have enough gravity to hold on to much hydrogen or helium gas since both of those are very light. So, even though carbon, nitrogen, oxygen and so on made up only two percent of the gas cloud from which Earth was formed, these heavier elements form the bulk of our planet and everything on it. Think about this: with the exception of hydrogen and some helium, the ground you walk on, the air you breath, you, everything is made of atoms that were created inside stars. When scientists first worked this out over the first half of the 20th Century, the famous astronomer Harlow Shapley commented, "We are brothers of the boulders, cousins of the clouds."

Frequently Occurring Word Combinations

ngrams of length 2

collocation frequency
billion years 2
fusion reactions 2
periodic table 2
gas cloud 2

Important Words

  1. accompanied
  2. accumulating
  3. air
  4. areas
  5. arose
  6. astronomer
  7. atoms
  8. attract
  9. attracted
  10. ball
  11. balls
  12. bang
  13. bear
  14. began
  15. belonging
  16. beneath
  17. big
  18. billion
  19. billions
  20. born
  21. boulders
  22. break
  23. breath
  24. brothers
  25. bulk
  26. call
  27. carbon
  28. century
  29. cloud
  30. clouds
  31. collapse
  32. commented
  33. completely
  34. composed
  35. consisting
  36. contact
  37. core
  38. counteract
  39. cousins
  40. create
  41. created
  42. dense
  43. density
  44. drew
  45. due
  46. earth
  47. eat
  48. ejected
  49. elements
  50. energy
  51. enriched
  52. equilibrium
  53. event
  54. eventually
  55. exception
  56. existed
  57. explosion
  58. explosions
  59. famous
  60. food
  61. force
  62. form
  63. formation
  64. formed
  65. forming
  66. frequently
  67. fuel
  68. fusion
  69. gas
  70. gold
  71. gravity
  72. great
  73. ground
  74. hand
  75. harlow
  76. heating
  77. heavier
  78. helium
  79. higher
  80. history
  81. hold
  82. hot
  83. hydrogen
  84. incidental
  85. including
  86. individual
  87. interstellar
  88. inwards
  89. iron
  90. large
  91. leaving
  92. life
  93. lifetime
  94. light
  95. living
  96. massive
  97. matches
  98. material
  99. matter
  100. means
  101. mind
  102. mix
  103. molecules
  104. nitrogen
  105. note
  106. nuclear
  107. objects
  108. occurs
  109. original
  110. oxygen
  111. percent
  112. periodic
  113. places
  114. planet
  115. planets
  116. point
  117. powerful
  118. process
  119. produce
  120. pull
  121. pulling
  122. pushing
  123. reactions
  124. release
  125. releases
  126. remaining
  127. repeats
  128. rest
  129. result
  130. resulted
  131. runs
  132. scientists
  133. shapley
  134. share
  135. shrinking
  136. silver
  137. simplest
  138. slightly
  139. small
  140. smash
  141. space
  142. star
  143. stars
  144. started
  145. strengthened
  146. strong
  147. submicroscopic
  148. sun
  149. supernova
  150. supernovas
  151. table
  152. turn
  153. unbelievably
  154. units
  155. universe
  156. uranium
  157. virtually
  158. walk
  159. wild
  160. worked
  161. wound
  162. years