1
00:00:02,367 --> 00:00:06,167
Narrator: ASTEROIDS ARE
THE EARTH'S NEMESIS.

2
00:00:06,167 --> 00:00:10,233
THEY'VE BLITZED OUR WORLD
FOR BILLIONS OF YEARS.

3
00:00:11,567 --> 00:00:14,400
Sykes: THIS TAKES A FEW SECONDS
TO CREATE.

4
00:00:14,400 --> 00:00:18,100
50,000 YEARS AGO WAS A VERY BAD
DAY FOR ANYBODY LIVING NEARBY.

5
00:00:18,100 --> 00:00:23,233
Narrator: YET ASTEROIDS ARE
ALSO A VALUABLE RESOURCE --

6
00:00:23,233 --> 00:00:27,533
GIANT BOULDERS
RICH WITH VALUABLE METALS,

7
00:00:27,533 --> 00:00:33,167
ICY MINIATURE WORLDS
WITH MORE FRESHWATER THAN EARTH.

8
00:00:33,167 --> 00:00:36,467
Kaku: ULTIMATELY, ASTEROIDS
MAY BE A STEPPING STONE

9
00:00:36,467 --> 00:00:39,900
BY WHICH WE CAN ONE DAY LEAVE
THE ENTIRE SOLAR SYSTEM.

10
00:00:39,900 --> 00:00:43,767
Narrator:
ASTEROIDS ARE PLANET BUILDERS.

11
00:00:43,767 --> 00:00:47,800
WITHOUT THEM,
OUR WORLD WOULD NOT BE HERE.

12
00:00:47,800 --> 00:00:49,933
WE OWE OUR VERY EXISTENCE
TO THESE THINGS.

13
00:00:49,933 --> 00:00:55,367
Narrator: THEY ARE THE GIVERS
AND TAKERS OF LIFE.

14
00:00:55,367 --> 00:00:58,367
-- Captions by VITAC --
www.vitac.com

15
00:00:58,367 --> 00:01:01,433
CAPTIONS PAID FOR BY
DISCOVERY COMMUNICATIONS

16
00:01:06,400 --> 00:01:09,733
THE NIGHT SKY IS FULL OF STARS,

17
00:01:09,733 --> 00:01:14,433
GALAXIES, PLANETS,
AND ASTEROIDS.

18
00:01:14,433 --> 00:01:16,667
Durda: "ASTEROID" ACTUALLY
MEANS "STAR-LIKE."

19
00:01:16,667 --> 00:01:18,400
EVEN IN THE VERY BEST
TELESCOPES,

20
00:01:18,400 --> 00:01:21,433
THEY LOOK LIKE NOTHING MORE THAN
JUST POINTS OF LIGHT IN THE SKY.

21
00:01:21,433 --> 00:01:25,067
Narrator:
THEY'RE COSMIC BOULDERS,

22
00:01:25,067 --> 00:01:27,600
AND THERE ARE TRILLIONS OF THEM,

23
00:01:27,600 --> 00:01:33,667
FROM THE SIZE OF A CAR TO GIANTS
HUNDREDS OF MILES ACROSS.

24
00:01:33,667 --> 00:01:39,600
TOGETHER THEY TELL THE STORY
OF HOW WE CAME TO BE.

25
00:01:39,600 --> 00:01:44,100
THE EARTH WAS MADE BY ASTEROIDS.

26
00:01:49,300 --> 00:01:53,333
4.5 BILLION YEARS AGO,

27
00:01:53,333 --> 00:01:56,900
THE SOLAR SYSTEM IS A VAST,
COSMIC WHIRLPOOL.

28
00:01:58,500 --> 00:02:03,067
DUST STICKS TOGETHER
TO CREATE ASTEROIDS.

29
00:02:04,367 --> 00:02:06,933
Krauss: IN OUR OWN SOLAR SYSTEM
AND IN EVERY SOLAR SYSTEM,

30
00:02:06,933 --> 00:02:09,767
THE FIRST OBJECTS TO FORM --
THE FIRST LARGE ROCKS --

31
00:02:09,767 --> 00:02:12,333
BEFORE PLANETS FORM,
ARE ESSENTIALLY ASTEROIDS.

32
00:02:12,333 --> 00:02:16,433
Narrator:
THERE ARE NO PLANETS YET.

33
00:02:16,433 --> 00:02:20,833
INSTEAD, TRILLIONS OF ROCKS
AND STONES

34
00:02:20,833 --> 00:02:24,600
SWIRL AROUND THE NEWLY BORN SUN.

35
00:02:24,600 --> 00:02:27,400
Schultz: IT WOULD'VE BEEN
A VERY STRANGE PLACE,

36
00:02:27,400 --> 00:02:29,100
KIND OF LIKE A MERRY-GO-ROUND

37
00:02:29,100 --> 00:02:31,800
OF ALL THESE OBJECTS ORBITING
AROUND THE SUN.

38
00:02:31,800 --> 00:02:34,067
AND THERE ARE MILLIONS
OF THESE ASTEROIDS

39
00:02:34,067 --> 00:02:36,800
THAT ARE JUST IN DIFFERENT SIZES
AND DIFFERENT SHAPES.

40
00:02:36,800 --> 00:02:40,500
Narrator:
THESE ANCIENT ASTEROIDS

41
00:02:40,500 --> 00:02:43,333
WILL SHAPE THE SOLAR SYSTEM

42
00:02:43,333 --> 00:02:46,600
AND BUILD THE PLANET WE LIVE ON.

43
00:02:46,600 --> 00:02:50,267
Durda: ASTEROIDS ARE SO MUCH
MORE THAN JUST ROCKS IN SPACE.

44
00:02:50,267 --> 00:02:52,200
THEY'RE THE BUILDING BLOCKS
OF OUR VERY OWN PLANET.

45
00:02:54,800 --> 00:02:58,433
Narrator:
BILLIONS OF SMALL ASTEROIDS

46
00:02:58,433 --> 00:03:02,100
MUST CLUMP TOGETHER
TO MAKE A PLANET.

47
00:03:02,100 --> 00:03:08,100
BUT ASTEROIDS MOVE AT THOUSANDS
OF MILES PER HOUR.

48
00:03:08,100 --> 00:03:12,200
GETTING THEM TO STICK IS HARD.

49
00:03:17,067 --> 00:03:18,633
WE'RE HERE AT THE STOCK CAR RACE

50
00:03:18,633 --> 00:03:21,433
TO SEE WHAT THE EARLY SOLAR
SYSTEM MAY HAVE LOOKED LIKE.

51
00:03:21,433 --> 00:03:23,700
[ ENGINES REV ]

52
00:03:23,700 --> 00:03:27,433
Narrator: HIGH-SPEED CAR
COLLISIONS CAUSE DAMAGE.

53
00:03:27,433 --> 00:03:30,467
PARTS SMASH OFF.

54
00:03:30,467 --> 00:03:33,633
ASTEROID COLLISIONS
ARE THE SAME.

55
00:03:34,933 --> 00:03:40,767
TO JOIN TOGETHER, SOMEHOW
THEY MUST COLLIDE AND STICK.

56
00:03:42,200 --> 00:03:45,300
STOCK CARS
SHOW HOW THIS HAPPENS.

57
00:03:45,300 --> 00:03:50,800
THEY MOVE FAST
BUT ALL IN THE SAME DIRECTION,

58
00:03:50,800 --> 00:03:55,500
JUST LIKE THE ASTEROIDS
IN THE EARLY SOLAR SYSTEM.

59
00:03:56,667 --> 00:04:01,367
WHEN COLLISIONS HAPPEN,
THEY'RE RELATIVELY GENTLE.

60
00:04:02,800 --> 00:04:07,533
INSTEAD OF SMASHING APART,
THEY JOIN TOGETHER.

61
00:04:08,767 --> 00:04:11,967
THESE ARE PLANETS IN THE MAKING.

62
00:04:11,967 --> 00:04:15,300
Schultz: THEY'RE GOING AROUND
ALMOST AT THE SAME SPEED,

63
00:04:15,300 --> 00:04:17,633
AND THEY BEGIN
TO STICK TOGETHER,

64
00:04:17,633 --> 00:04:20,467
AND THAT'S HOW PLANETS
BEGIN TO FORM.

65
00:04:20,467 --> 00:04:27,100
Narrator: ASTEROIDS GATHER
INTO ROCK PILES,

66
00:04:27,100 --> 00:04:30,067
LIKE TWO CARS LOCKED TOGETHER.

67
00:04:31,500 --> 00:04:36,333
AS MORE ASTEROIDS COLLIDE,
THE ROCK PILES GROW.

68
00:04:37,833 --> 00:04:42,167
BUILDING WHOLE PLANETS THIS WAY
WOULD TAKE BILLIONS OF YEARS.

69
00:04:43,600 --> 00:04:48,533
YET THE PLANETS FORMED
IN JUST A FEW MILLION YEARS.

70
00:04:48,533 --> 00:04:50,167
HOW?

71
00:04:50,167 --> 00:04:54,067
WHEN THE ROCK PILES
REACH MOUNTAIN SIZE,

72
00:04:54,067 --> 00:04:57,067
GRAVITY SPEEDS UP THE PROCESS.

73
00:04:57,067 --> 00:04:59,467
Plait: GRAVITY STARTED
TO BECOME IMPORTANT

74
00:04:59,467 --> 00:05:02,833
WHEN THEY WERE ABOUT THE SIZE
OF ONE OF THE ROCKY MOUNTAINS,

75
00:05:02,833 --> 00:05:04,300
LIKE PIKES PEAK BEHIND ME.

76
00:05:04,300 --> 00:05:06,733
IT WAS WHEN THEY WERE
SEVERAL MILES ACROSS

77
00:05:06,733 --> 00:05:08,167
THAT THEY HAD ENOUGH MASS

78
00:05:08,167 --> 00:05:11,067
THAT THEIR GRAVITY COULD START
TO DRAW MATERIAL IN.

79
00:05:11,067 --> 00:05:12,767
NOW, IF THE EARTH WEREN'T HERE,

80
00:05:12,767 --> 00:05:15,867
AND IT WERE JUST PIKES PEAK
OVER THERE A FEW MILES AWAY,

81
00:05:15,867 --> 00:05:18,467
I WOULD VERY SLOWLY
START TO DRIFT TOWARD IT,

82
00:05:18,467 --> 00:05:19,867
FASTER AND FASTER,

83
00:05:19,867 --> 00:05:22,667
ACCELERATING THE WHOLE WAY
UNTIL I ACTUALLY IMPACTED IT.

84
00:05:22,667 --> 00:05:24,300
THE GRAVITY WOULD DRAW ME IN.

85
00:05:24,300 --> 00:05:25,433
IT WOULD PULL ON ME

86
00:05:25,433 --> 00:05:27,833
UNTIL I ACTUALLY HIT
THE MOUNTAIN ITSELF.

87
00:05:30,567 --> 00:05:34,067
Narrator: LARGE ASTEROIDS
ARE MOUNTAINS IN SPACE.

88
00:05:35,800 --> 00:05:39,267
THE EARLY SOLAR SYSTEM
IS FULL OF THEM.

89
00:05:39,267 --> 00:05:43,600
THEIR GRAVITY PULLS
OTHER ASTEROIDS TOWARD THEM.

90
00:05:46,067 --> 00:05:49,533
THE LARGER AN ASTEROID BECOMES,

91
00:05:49,533 --> 00:05:55,333
THE MORE ROCKS IT PULLS IN
AND THE FASTER IT GROWS.

92
00:05:55,333 --> 00:05:58,700
Plait: AT THAT POINT,
THE EVENTS HAPPEN VERY QUICKLY.

93
00:05:58,700 --> 00:06:01,500
IT WOULD ACTUALLY DRAW THAT
STUFF IN AND GROW VERY RAPIDLY.

94
00:06:01,500 --> 00:06:07,233
Narrator: ONE OF THESE EARLY
SPACE MOUNTAINS KEEPS ON GROWING

95
00:06:07,233 --> 00:06:11,300
UNTIL THERE ARE NO ROCKS LEFT
TO PULL IN.

96
00:06:12,733 --> 00:06:16,067
IT'S NO LONGER AN ASTEROID.

97
00:06:16,067 --> 00:06:20,367
IT'S A YOUNG PLANET --
THE EARTH.

98
00:06:22,167 --> 00:06:24,500
Plait: ALL OF THE PLANETS,
EVEN THE EARTH,

99
00:06:24,500 --> 00:06:26,533
THEY OWE THEIR EXISTENCE
TO THE FACT

100
00:06:26,533 --> 00:06:28,600
THAT THERE WERE ASTEROIDS
BACK THEN.

101
00:06:28,600 --> 00:06:33,767
Narrator: THIS IS HOW ALL
ROCKY PLANETS FORM --

102
00:06:33,767 --> 00:06:39,500
ASTEROIDS JOIN TOGETHER
UNTIL THERE ARE NO MORE LEFT.

103
00:06:39,500 --> 00:06:43,567
MERCURY, VENUS,

104
00:06:43,567 --> 00:06:46,500
EARTH, AND MARS

105
00:06:46,500 --> 00:06:50,333
ARE ALL OVERGROWN ASTEROIDS.

106
00:06:51,900 --> 00:06:56,067
BUT BEYOND MARS,
SOMETHING WENT WRONG.

107
00:06:56,067 --> 00:06:58,933
NO ROCKY PLANETS.

108
00:06:58,933 --> 00:07:03,267
INSTEAD, BILLIONS OF ROCKS
AND BOULDERS

109
00:07:03,267 --> 00:07:08,300
THAT NEVER JOINED TOGETHER --
THE ASTEROID BELT.

110
00:07:11,267 --> 00:07:14,867
OUT HERE,
CONSTRUCTION CAME TO A HALT

111
00:07:14,867 --> 00:07:18,300
BEFORE A ROCKY PLANET
COULD FORM --

112
00:07:18,300 --> 00:07:20,167
BECAUSE OF JUPITER.

113
00:07:22,333 --> 00:07:27,167
THE GAS GIANT HAD ALREADY
FORMED NEARBY.

114
00:07:28,200 --> 00:07:30,167
Kaku: JUPITER IS HUMONGOUS.

115
00:07:30,167 --> 00:07:32,167
IT'S THE 800-POUND GORILLA.

116
00:07:32,167 --> 00:07:35,200
IT DOMINATES EVERYTHING
GRAVITATIONALLY.

117
00:07:35,200 --> 00:07:38,433
Narrator:
4.5 BILLION YEARS AGO,

118
00:07:38,433 --> 00:07:41,267
JUPITER'S GRAVITY CAUSES HAVOC.

119
00:07:41,267 --> 00:07:47,367
IT FLINGS ASTEROIDS
IN EVERY DIRECTION.

120
00:07:47,367 --> 00:07:52,367
GIANT BOULDERS SCATTER
FROM THEIR REGULAR ORBITS

121
00:07:52,367 --> 00:07:55,167
ONTO EXTREME CHAOTIC PATHS.

122
00:07:57,267 --> 00:08:03,067
THE STOCK CAR RACE ENDS,
AND THE DEMOLITION DERBY BEGINS.

123
00:08:05,233 --> 00:08:06,800
ONCE JUPITER GOT INVOLVED,

124
00:08:06,800 --> 00:08:10,133
THE SOLAR SYSTEM BEGAN TO LOOK
LIKE A DEMOLITION DERBY --

125
00:08:10,133 --> 00:08:11,600
THINGS COLLIDING
WITH EACH OTHER,

126
00:08:11,600 --> 00:08:13,433
GOING IN ALL SORTS
OF DIFFERENT DIRECTIONS.

127
00:08:15,433 --> 00:08:18,100
Narrator: A COSMIC PILEUP --

128
00:08:18,100 --> 00:08:23,733
ROCKS SMASH INTO EACH OTHER
FROM EVERY DIRECTION,

129
00:08:23,733 --> 00:08:26,067
VIOLENT, CHAOTIC COLLISIONS.

130
00:08:27,300 --> 00:08:31,300
THESE ROCKS
DON'T CLUMP TOGETHER.

131
00:08:31,300 --> 00:08:34,067
THEY SHATTER...

132
00:08:34,067 --> 00:08:38,700
AND CREATE THE ASTEROID BELT.

133
00:08:38,700 --> 00:08:44,533
VIOLENT COLLISIONS STILL ROCK
THE ASTEROID BELT TODAY.

134
00:08:44,533 --> 00:08:50,200
IN 2010, THE HUBBLE SPACE
TELESCOPE CAPTURED THIS --

135
00:08:50,200 --> 00:08:55,167
THE AFTERMATH
OF A HYPERVELOCITY COLLISION.

136
00:08:57,633 --> 00:09:02,200
ASTEROIDS CAN BOTH CREATE
AND DESTROY.

137
00:09:02,200 --> 00:09:08,067
IF MANY OF THEM COME TOGETHER
GENTLY, YOU GET PLANETS.

138
00:09:08,067 --> 00:09:14,067
TOO MUCH VIOLENCE AND YOU GET
THE ASTEROID BELT --

139
00:09:14,067 --> 00:09:17,500
BILLIONS OF ROCKS AND BOULDERS,

140
00:09:17,500 --> 00:09:22,433
A GRAVEYARD FOR A PLANET
THAT NEVER FORMED.

141
00:09:22,433 --> 00:09:27,767
THE ASTEROID BELT
IS A MYSTERIOUS REALM,

142
00:09:27,767 --> 00:09:32,533
FULL OF DANGER
AND FULL OF PROMISE,

143
00:09:32,533 --> 00:09:38,067
A NEW FRONTIER JUST WAITING
TO BE EXPLORED.

144
00:09:49,667 --> 00:09:55,133
Narrator: ASTEROIDS ARE AS
DIVERSE AS PLANETS OR MOONS.

145
00:09:55,133 --> 00:09:58,733
SOME ARE METALLIC...

146
00:09:58,733 --> 00:10:01,067
SOME ROCKY...

147
00:10:01,067 --> 00:10:03,233
SOME ICY.

148
00:10:05,667 --> 00:10:10,900
SOME EVEN HAVE THEIR OWN MOONS.

149
00:10:10,900 --> 00:10:16,167
THEY COME IN ALL SHAPES
AND SIZES...

150
00:10:16,167 --> 00:10:22,533
FROM BOULDERS ALL THE WAY
TO MINIATURE WORLDS.

151
00:10:24,800 --> 00:10:28,033
AND THEY'RE EVERYWHERE.

152
00:10:28,033 --> 00:10:33,233
DISTANT SOLAR SYSTEMS HAVE
THEIR OWN ASTEROID BELTS.

153
00:10:33,233 --> 00:10:39,933
THE STAR EPSILON ERIDANI
IS JUST 10 LIGHT-YEARS AWAY.

154
00:10:39,933 --> 00:10:45,000
IT HAS NOT ONE
BUT TWO ASTEROID BELTS.

155
00:10:45,000 --> 00:10:49,700
ANOTHER STAR HAS A BELT
25 TIMES LARGER

156
00:10:49,700 --> 00:10:51,833
THAN OUR OWN.

157
00:10:51,833 --> 00:10:55,133
Krauss: IF YOU'RE ACTUALLY LIVING
ON A PLANET IN THAT SOLAR SYSTEM,

158
00:10:55,133 --> 00:10:57,067
THE ASTEROID BELT
WOULD LOOK LIKE A --

159
00:10:57,067 --> 00:10:58,800
MUCH BRIGHTER
THAN THE MILKY WAY,

160
00:10:58,800 --> 00:11:00,633
A BIG STREAK
ACROSS THE NIGHT SKY.

161
00:11:00,633 --> 00:11:05,067
Narrator: ASTEROID BELTS
ARE THE SCRAPS LEFT OVER

162
00:11:05,067 --> 00:11:07,333
AFTER PLANETS HAVE FORMED,

163
00:11:07,333 --> 00:11:11,533
SO THEY TELL US A LOT
ABOUT THEIR SOLAR SYSTEM.

164
00:11:13,167 --> 00:11:18,167
OUR ASTEROID BELT
IS FULL OF VARIETY --

165
00:11:18,167 --> 00:11:22,333
MILLIONS OF STRANGE ASTEROIDS,

166
00:11:22,333 --> 00:11:26,100
EACH WITH A STORY TO TELL.

167
00:11:26,100 --> 00:11:29,533
YET WE HAVE BARELY
EXPLORED IT AT ALL.

168
00:11:31,900 --> 00:11:34,967
THAT'S ABOUT TO CHANGE.

169
00:11:34,967 --> 00:11:40,533
THE FIRST MISSION TO THE
ASTEROID BELT IS UNDER WAY --

170
00:11:40,533 --> 00:11:43,167
THE DAWN PROBE.

171
00:11:43,167 --> 00:11:45,267
ITS GOAL?

172
00:11:45,267 --> 00:11:50,500
TO EXPLORE A MYSTERIOUS,
DISTANT REALM.

173
00:11:50,500 --> 00:11:53,333
Plait: WE'RE GONNA LEARN MORE
ABOUT THE MAIN BELT ASTEROIDS

174
00:11:53,333 --> 00:11:54,400
FROM THIS ONE MISSION

175
00:11:54,400 --> 00:11:55,667
THAN WE WILL HAVE

176
00:11:55,667 --> 00:11:58,633
SINCE WE DISCOVERED THE ASTEROID
BELT IN THE FIRST PLACE.

177
00:11:58,633 --> 00:12:01,333
Narrator: IN JULY 2011,

178
00:12:01,333 --> 00:12:05,267
DAWN ARRIVED AT ITS FIRST TARGET

179
00:12:05,267 --> 00:12:09,467
AND SENT BACK THESE PICTURES.

180
00:12:09,467 --> 00:12:14,433
VESTA IS THE SECOND-LARGEST
ASTEROID IN THE BELT.

181
00:12:14,433 --> 00:12:18,200
IT ALMOST BECAME A PLANET.

182
00:12:18,200 --> 00:12:24,633
THEN JUPITER'S MASSIVE GRAVITY
STUNTED ITS GROWTH.

183
00:12:24,633 --> 00:12:29,100
TODAY IT'S A MINIATURE WORLD.

184
00:12:29,100 --> 00:12:32,167
Thaller: ONE OF THE COMMON
MISCONCEPTIONS ABOUT THE ASTEROID BELT

185
00:12:32,167 --> 00:12:33,633
IS THAT THINGS ARE FAIRLY SMALL.

186
00:12:33,633 --> 00:12:35,300
BUT SOME OF
THE LARGEST ASTEROIDS

187
00:12:35,300 --> 00:12:37,800
ARE REALLY MORE CORRECTLY
THOUGHT OF AS MINOR PLANETS.

188
00:12:37,800 --> 00:12:39,600
THEY'RE SEVERAL HUNDRED
MILES ACROSS.

189
00:12:39,600 --> 00:12:43,900
Narrator:
VESTA EVEN HAS A MOUNTAIN

190
00:12:43,900 --> 00:12:47,500
THREE TIMES HIGHER THAN EVEREST.

191
00:12:47,500 --> 00:12:51,767
MARK SYKES IS CO-INVESTIGATOR
OF THE MISSION.

192
00:12:51,767 --> 00:12:54,433
Sykes:
IT'S JUST A REAL EXCITEMENT

193
00:12:54,433 --> 00:12:56,833
BECAUSE YOU'RE SEEING A NEW
WORLD FOR THE FIRST TIME,

194
00:12:56,833 --> 00:12:58,733
AND YOU KNOW JUST ENOUGH
TO BE DANGEROUS

195
00:12:58,733 --> 00:13:01,133
IN TRYING TO EXPLAIN WHAT IT IS
THAT YOU'RE SEEING.

196
00:13:01,133 --> 00:13:06,633
Narrator: VESTA IS LIKE
A SNAPSHOT OF THE INFANT EARTH

197
00:13:06,633 --> 00:13:10,567
WHEN IT WAS JUST AS WIDE
AS ARIZONA.

198
00:13:12,233 --> 00:13:14,433
Sykes: WE'RE SEEING PERHAPS

199
00:13:14,433 --> 00:13:18,100
WHAT AN EMBRYONIC, EARLY
TERRESTRIAL PLANET LIKE EARTH

200
00:13:18,100 --> 00:13:23,400
LOOKED LIKE IN THE FIRST FEW
MILLION YEARS OF ITS HISTORY.

201
00:13:23,400 --> 00:13:27,667
Narrator: THE DAWN PROBE
HAS ALREADY FOUND

202
00:13:27,667 --> 00:13:32,200
THAT VESTA HAS AN IRON CORE
LIKE THE EARTH --

203
00:13:32,200 --> 00:13:35,067
EVIDENCE THAT
THE EARTH'S CORE FORMED

204
00:13:35,067 --> 00:13:39,167
WHEN THE PLANET WAS STILL YOUNG.

205
00:13:39,167 --> 00:13:43,567
THIS STUNTED WORLD
OFFERS US A WINDOW

206
00:13:43,567 --> 00:13:46,700
ON THE EARTH'S DISTANT PAST.

207
00:13:46,700 --> 00:13:52,100
Sykes: WE'RE SEEING THINGS THAT
WE DIDN'T NECESSARILY EXPECT,

208
00:13:52,100 --> 00:13:53,933
BUT THAT'S WHAT MAKES IT FUN.

209
00:13:53,933 --> 00:13:57,267
Narrator: AFTER VESTA,

210
00:13:57,267 --> 00:14:00,067
THE DAWN MISSION WILL HEAD

211
00:14:00,067 --> 00:14:04,067
INTO THE ASTEROID BELT'S
OUTER REACHES

212
00:14:04,067 --> 00:14:07,600
TO EXPLORE AN ICY,
PRIMEVAL WORLD

213
00:14:07,600 --> 00:14:10,633
FOUR TIMES BIGGER THAN VESTA.

214
00:14:10,633 --> 00:14:17,533
THERE, DAWN AIMS TO SETTLE
ANOTHER MYSTERY

215
00:14:17,533 --> 00:14:21,200
ABOUT THE EARTH'S PAST --

216
00:14:21,200 --> 00:14:26,067
WHERE DID OUR OCEANS COME FROM?

217
00:14:36,600 --> 00:14:42,900
Narrator: THE ASTEROID BELT IS
ANCIENT, VIOLENT, AND REMOTE --

218
00:14:42,900 --> 00:14:47,900
HUNDREDS OF MILLIONS OF MILES
FROM EARTH.

219
00:14:47,900 --> 00:14:53,367
BUT NOT ALL ASTEROIDS
STAY IN THE ASTEROID BELT.

220
00:14:53,367 --> 00:14:58,067
THEY CAN ROAM ALL OVER
THE SOLAR SYSTEM.

221
00:14:58,067 --> 00:15:03,567
THE MOON'S SURFACE RECORDS
A VIOLENT PAST --

222
00:15:03,567 --> 00:15:07,167
A MASSIVE, COSMIC BOMBARDMENT.

223
00:15:07,167 --> 00:15:11,100
WE SEE EVIDENCE EVERY NIGHT
WHEN THE MOON COMES OUT.

224
00:15:11,100 --> 00:15:12,367
WHAT DO WE SEE?

225
00:15:12,367 --> 00:15:14,567
A POCKMARKED, BARREN WORLD --

226
00:15:14,567 --> 00:15:18,500
EVIDENCE THAT THERE WAS
AN INTENSE RAIN OF ASTEROIDS

227
00:15:18,500 --> 00:15:21,533
AND DEBRIS THAT CAME
FROM OUTER SPACE,

228
00:15:21,533 --> 00:15:25,133
COMPLETELY DISFIGURING
THE SURFACE OF THE MOON.

229
00:15:25,133 --> 00:15:29,700
Narrator: MILLIONS OF CRATERS
COVER THE MOON,

230
00:15:29,700 --> 00:15:34,200
INCLUDING THE LARGEST
IN THE SOLAR SYSTEM --

231
00:15:34,200 --> 00:15:38,600
1,500 MILES ACROSS,

232
00:15:38,600 --> 00:15:44,433
ITSELF SCARRED BY THOUSANDS
OF SMALLER CRATERS.

233
00:15:44,433 --> 00:15:48,833
A STORM OF ASTEROIDS
BLASTED THE MOON

234
00:15:48,833 --> 00:15:51,967
4 BILLION YEARS AGO.

235
00:15:51,967 --> 00:15:55,733
AND IF THAT HAPPENED
TO THE MOON,

236
00:15:55,733 --> 00:15:59,800
IT MUST ALSO HAVE HAPPENED
TO EARTH.

237
00:15:59,800 --> 00:16:04,500
Durda: THE EARTH IS A MUCH BIGGER,
MORE MASSIVE TARGET IN SPACE.

238
00:16:04,500 --> 00:16:07,167
FOR EVERY ONE OF THOSE CRATERS
YOU SEE ON THE MOON,

239
00:16:07,167 --> 00:16:09,233
YOU'VE GOT TO IMAGINE
50 OR 60 CRATERS

240
00:16:09,233 --> 00:16:10,567
HERE ON THE PLANET EARTH.

241
00:16:13,667 --> 00:16:18,067
Kaku: THE IMPACTS BACK THEN
MUST HAVE BEEN HORRENDOUS.

242
00:16:18,067 --> 00:16:22,267
EVERY FEW WEEKS, A GIGANTIC
OBJECT HURTLING FROM OUTER SPACE

243
00:16:22,267 --> 00:16:27,067
GOUGING OUT A HUGE CHUNK
OF THE PLANET EARTH.

244
00:16:27,067 --> 00:16:31,267
Narrator: WE CALL IT
THE LATE HEAVY BOMBARDMENT.

245
00:16:32,533 --> 00:16:38,800
FOR 200 MILLION YEARS,
FIREBALLS RAINED FROM THE SKY.

246
00:16:43,133 --> 00:16:46,133
THE IMPACTS TRIGGER EARTHQUAKES

247
00:16:46,133 --> 00:16:49,733
BIGGER THAN ANY
IN RECORDED HISTORY.

248
00:16:51,500 --> 00:16:54,867
10,000-MILE-PER-HOUR HURRICANES

249
00:16:54,867 --> 00:16:58,133
RIP THROUGH
EARTH'S PRIMITIVE ATMOSPHERE.

250
00:17:03,833 --> 00:17:09,900
BUT ASTEROIDS ALSO BRING
A NEW SUBSTANCE TO EARTH.

251
00:17:09,900 --> 00:17:14,367
SOME ASTEROIDS CONTAIN ICE --

252
00:17:14,367 --> 00:17:20,067
FROZEN WATER THAT MELTS
ON IMPACT.

253
00:17:20,067 --> 00:17:23,733
EACH ASTEROID
BRINGS A LITTLE MORE.

254
00:17:25,433 --> 00:17:29,867
BUT COULD ASTEROIDS
REALLY BRING ENOUGH WATER

255
00:17:29,867 --> 00:17:32,800
TO COVER 2/3 OF OUR PLANET?

256
00:17:32,800 --> 00:17:35,767
ONE OF THE QUESTIONS WE HAVE IS
HOW DID WATER GET TO THE EARTH.

257
00:17:35,767 --> 00:17:37,667
BECAUSE THE ORIGINAL EARTH,
WE THINK,

258
00:17:37,667 --> 00:17:38,933
WAS VERY HOT AND VERY DRY.

259
00:17:38,933 --> 00:17:45,733
Narrator: NASA'S DAWN PROBE
AIMS TO FIND OUT.

260
00:17:45,733 --> 00:17:52,133
THE ASTEROID BELT STILL CONTAINS
ICY ASTEROIDS TO THIS DAY

261
00:17:52,133 --> 00:17:56,233
IN THE COLDEST,
MOST DISTANT PART.

262
00:17:56,233 --> 00:17:58,567
IN 2015,

263
00:17:58,567 --> 00:18:03,567
DAWN WILL ARRIVE AT THE SOLAR
SYSTEM'S LARGEST ASTEROID --

264
00:18:03,567 --> 00:18:05,067
CERES.

265
00:18:05,067 --> 00:18:09,233
Krauss: CERES IS 1/3 THE MASS
OF THE ENTIRE ASTEROID BELT

266
00:18:09,233 --> 00:18:12,367
AND FOUR TIMES AS LARGE
AS ANY OTHER KNOWN ASTEROID.

267
00:18:12,367 --> 00:18:18,600
Narrator: A LOT OF IT
LOOKS LIKE PURE ICE.

268
00:18:18,600 --> 00:18:24,067
Sykes: CERES HAS A ROCKY
INTERIOR AND ICE-RICH MANTLE.

269
00:18:24,067 --> 00:18:27,700
IT'S FAR ENOUGH AWAY FROM
THE SUN -- IT'S COLD ENOUGH --

270
00:18:27,700 --> 00:18:28,967
THAT IT'S STABLE.

271
00:18:28,967 --> 00:18:33,267
Narrator:
CERES IS JUST 600 MILES WIDE,

272
00:18:33,267 --> 00:18:37,967
YET THERE MAY BE
MORE FROZEN WATER HERE

273
00:18:37,967 --> 00:18:41,400
THAN ALL THE FRESHWATER
ON EARTH.

274
00:18:41,400 --> 00:18:46,433
THE DAWN MISSION WILL FIND OUT
FOR SURE.

275
00:18:46,433 --> 00:18:51,400
IF CERES REALLY DOES HOLD
SO MUCH ICE,

276
00:18:51,400 --> 00:18:56,167
IT COULD HELP EXPLAIN WHY
THE EARTH HAS SO MUCH WATER.

277
00:18:58,067 --> 00:19:04,333
WHEN ASTEROIDS BOMBARDED
THE EARTH 4 BILLION YEARS AGO,

278
00:19:04,333 --> 00:19:07,867
MASSIVE ICY BODIES LIKE CERES

279
00:19:07,867 --> 00:19:12,867
COULD'VE BROUGHT VAST AMOUNTS
OF WATER.

280
00:19:12,867 --> 00:19:15,700
Kaku: WATER ITSELF,
IN THE FORM OF ICE,

281
00:19:15,700 --> 00:19:17,533
CAME DOWN FROM THE HEAVENS

282
00:19:17,533 --> 00:19:20,367
TO CREATE THE LUSH OCEANS
OF THE EARTH.

283
00:19:20,367 --> 00:19:24,200
Narrator:
AND NOT JUST THE OCEANS.

284
00:19:24,200 --> 00:19:28,633
CLOUDS, RIVERS...

285
00:19:28,633 --> 00:19:33,433
GLACIERS MAY ALL HAVE COME
FROM SPACE.

286
00:19:35,400 --> 00:19:38,467
THE DAWN MISSION
MAY UNCOVER SOMETHING

287
00:19:38,467 --> 00:19:41,867
EVEN MORE SIGNIFICANT ON CERES.

288
00:19:41,867 --> 00:19:47,633
IT MAY FIND AN OCEAN
UNDERNEATH THE ICE --

289
00:19:47,633 --> 00:19:51,067
AN INNER MANTLE OF LIQUID WATER,

290
00:19:51,067 --> 00:19:56,067
MELTED BY HEAT FROM
THE DWARF PLANET'S CORE.

291
00:19:57,367 --> 00:20:01,667
LIFE AS WE KNOW IT
DEPENDS ON WATER.

292
00:20:01,667 --> 00:20:07,633
WHEREVER WE FIND WATER,
WE MAY FIND THE SPARK OF LIFE.

293
00:20:09,267 --> 00:20:11,867
IF THERE IS A LIQUID-WATER OCEAN
UNDERNEATH THE SURFACE TODAY,

294
00:20:11,867 --> 00:20:12,900
THAT BEGS THE QUESTION

295
00:20:12,900 --> 00:20:14,533
OF WHETHER THERE COULD BE
LIFE THERE.

296
00:20:14,533 --> 00:20:18,933
Narrator: EXTRATERRESTRIAL LIFE
COULD'VE STARTED

297
00:20:18,933 --> 00:20:21,067
IN THE ASTEROID BELT.

298
00:20:23,533 --> 00:20:28,033
CERES COULD BE HOME
TO BASIC LIFE-FORMS

299
00:20:28,033 --> 00:20:32,300
FLOURISHING
IN A SUBSURFACE OCEAN.

300
00:20:37,167 --> 00:20:42,000
IF ASTEROIDS LIKE CERES
CAN SUPPORT LIFE,

301
00:20:42,000 --> 00:20:47,133
THAT COULD REVEAL HOW LIFE
STARTED ON EARTH.

302
00:20:47,133 --> 00:20:50,733
4 BILLION YEARS AGO,

303
00:20:50,733 --> 00:20:56,600
ASTEROIDS BOMBARDED
THE YOUNG EARTH.

304
00:20:56,600 --> 00:21:02,300
THEY BROUGHT WATER,
AND THEY MAY HAVE BROUGHT LIFE.

305
00:21:04,233 --> 00:21:07,533
FROM THE ASTEROID BELT

306
00:21:07,533 --> 00:21:11,100
TO EARTH'S NEW OCEANS...

307
00:21:11,100 --> 00:21:14,500
PRIMITIVE ORGANISMS THAT THRIVED

308
00:21:14,500 --> 00:21:20,467
AND ULTIMATELY EVOLVED INTO ALL
THE EARTH'S CREATURES --

309
00:21:20,467 --> 00:21:25,533
A PLANET THAT BRIMS WITH LIFE.

310
00:21:26,567 --> 00:21:30,933
OUR EARLIEST ANCESTORS
MAY HAVE ARRIVED

311
00:21:30,933 --> 00:21:33,467
FROM THE ASTEROID BELT.

312
00:21:33,467 --> 00:21:36,933
PERHAPS THESE LITTLE WORLDS
COULD BE INCUBATORS OF LIFE

313
00:21:36,933 --> 00:21:38,733
THROUGHOUT OUR SOLAR SYSTEM,

314
00:21:38,733 --> 00:21:42,100
MAYBE EVEN IN OTHER SOLAR
SYSTEMS AROUND OTHER STARS.

315
00:21:42,100 --> 00:21:45,867
Narrator:
ASTEROIDS MAY BRING LIFE

316
00:21:45,867 --> 00:21:49,600
TO WORLDS THROUGHOUT
THE UNIVERSE.

317
00:21:49,600 --> 00:21:53,333
THEY MAY ALSO BRING DEATH.

318
00:22:01,567 --> 00:22:07,967
Narrator: ASTEROIDS ARE CRUCIAL
TO LIFE IN THE UNIVERSE.

319
00:22:07,967 --> 00:22:14,167
BUT ONCE LIFE GETS STARTED,
ASTEROIDS CAN ALSO END IT.

320
00:22:14,167 --> 00:22:16,233
ASTEROIDS REALLY HAVE
TWO SIDES TO THEM.

321
00:22:16,233 --> 00:22:18,200
THEY'RE SORT OF CREATION
AND DESTRUCTION

322
00:22:18,200 --> 00:22:19,533
ALL WRAPPED UP TOGETHER.

323
00:22:19,533 --> 00:22:24,200
Narrator: PLANET EARTH IS RIGHT
IN THE FIRING LINE.

324
00:22:24,200 --> 00:22:26,100
Durda: WE'VE COME TO REALIZE
IN RECENT YEARS

325
00:22:26,100 --> 00:22:28,767
THAT WE LIVE IN THIS KIND OF
A COSMIC SHOOTING GALLERY.

326
00:22:28,767 --> 00:22:35,067
Narrator: ASTRONAUTS
WITNESS THIS FIRSTHAND.

327
00:22:35,067 --> 00:22:39,067
WHEN I FLEW ON APOLLO 9 AND I
WENT OUTSIDE THE SPACECRAFT,

328
00:22:39,067 --> 00:22:41,267
IT'S VERY LIKELY THAT I WAS HIT

329
00:22:41,267 --> 00:22:44,333
BY, YOU KNOW,
A VERY, VERY SMALL ASTEROID.

330
00:22:44,333 --> 00:22:49,067
AND, YOU KNOW, IT WILL MAKE
A HOLE IN A SPACE SUIT.

331
00:22:49,067 --> 00:22:53,767
Narrator: MOST OBJECTS IN
THE EARTH'S VICINITY ARE TINY,

332
00:22:53,767 --> 00:22:57,700
BUT THEY MOVE AT THOUSANDS
OF MILES PER HOUR.

333
00:22:57,700 --> 00:23:00,700
SO, THE SUITS
ARE VERY, VERY WELL-BUILT,

334
00:23:00,700 --> 00:23:03,767
THE RESULT OF WHICH
IS THEY'RE VERY HEAVY.

335
00:23:03,767 --> 00:23:07,300
BUT, YOU KNOW, WE'VE NEVER HAD
ONE PENETRATED YET.

336
00:23:07,300 --> 00:23:12,100
Narrator: THE EARTH, TOO,
HAS BUILT-IN PROTECTION

337
00:23:12,100 --> 00:23:17,300
FROM SMALL ASTEROIDS --
THE ATMOSPHERE.

338
00:23:17,300 --> 00:23:21,867
WHEN ASTEROIDS HIT
THE ATMOSPHERE, THEY BURN.

339
00:23:21,867 --> 00:23:23,333
Schweickart: I CAN REMEMBER,

340
00:23:23,333 --> 00:23:26,767
ONE NIGHT WHEN WE WERE LOOKING
DOWN AT THE DARK EARTH,

341
00:23:26,767 --> 00:23:30,267
AND I KEPT THINKING I SAW
AN OCCASIONAL FLASH OF LIGHT,

342
00:23:30,267 --> 00:23:31,600
BUT I WASN'T SURE.

343
00:23:31,600 --> 00:23:35,067
AND THEN SUDDENLY, WE'RE
REALIZING, OF COURSE, YOU KNOW,

344
00:23:35,067 --> 00:23:37,400
WE'RE LOOKING AT SHOOTING STARS.

345
00:23:42,367 --> 00:23:45,233
Krauss: MOST PEOPLE DON'T
REALIZE THAT ON A GIVEN NIGHT,

346
00:23:45,233 --> 00:23:48,067
IF YOU LIE IN THE GRASS
AND LOOK UP AT THE NIGHT SKY,

347
00:23:48,067 --> 00:23:51,400
YOU'LL SEE SHOOTING STARS,
MANY OF THEM EACH HOUR.

348
00:23:52,533 --> 00:23:57,933
Narrator: MOST SHOOTING STARS
ARE THE SIZE OF GRAINS OF SAND.

349
00:23:57,933 --> 00:24:00,433
THESE BURN UP.

350
00:24:02,700 --> 00:24:04,967
BUT LARGER SPACE ROCKS

351
00:24:04,967 --> 00:24:08,900
CAN PUNCH RIGHT THROUGH
TO THE GROUND.

352
00:24:08,900 --> 00:24:11,567
HERE'S THE PROOF --

353
00:24:11,567 --> 00:24:14,867
METEOR CRATER IN ARIZONA,

354
00:24:14,867 --> 00:24:18,800
GOUGED OUT BY AN ASTEROID

355
00:24:18,800 --> 00:24:22,200
JUST 150 FEET ACROSS.

356
00:24:22,200 --> 00:24:26,667
Sykes: YOU CAN SEE THE HUGE
FORCE THAT EXCAVATED THIS,

357
00:24:26,667 --> 00:24:29,867
AND YOU CAN ALSO SEE
THE LAYERS OF MATERIAL

358
00:24:29,867 --> 00:24:34,533
THAT WERE TURNED OVER
AS THE CRATER WAS EXCAVATED,

359
00:24:34,533 --> 00:24:37,300
AND SO SOME OF THESE ROCKS
AROUND HERE

360
00:24:37,300 --> 00:24:40,667
ARE KIND OF UPSIDE-DOWN
FROM WHERE THEY STARTED.

361
00:24:40,667 --> 00:24:44,833
Narrator: THERE HAVE BEEN
MILLIONS OF IMPACTS LIKE THIS

362
00:24:44,833 --> 00:24:47,233
IN EARTH'S PAST.

363
00:24:47,233 --> 00:24:49,967
THERE WILL BE MORE.

364
00:24:49,967 --> 00:24:54,800
IMAGINE A CITY
WHERE METEOR CRATER IS NOW.

365
00:24:54,800 --> 00:24:58,433
YOU CAN SEE A FIREBALL COMING
THROUGH THE SKY VERY QUICKLY.

366
00:24:58,433 --> 00:25:01,433
YOU KNOW, THIS THING IS MOVING
AT EIGHT MILES A SECOND,

367
00:25:01,433 --> 00:25:03,367
AND SO IT WOULDN'T TAKE
VERY LONG

368
00:25:03,367 --> 00:25:06,167
FOR IT TO MOVE ACROSS THE SKY
AND STRIKE THE GROUND.

369
00:25:06,167 --> 00:25:10,733
Narrator: HEAT FROM THE FIREBALL
SCORCHES THE SURFACE.

370
00:25:10,733 --> 00:25:15,067
BUT MOST DAMAGE COMES
AFTER THE IMPACT.

371
00:25:17,167 --> 00:25:19,067
ONCE IT STRIKES THE GROUND,

372
00:25:19,067 --> 00:25:21,633
THIS TAKES A FEW SECONDS
TO CREATE.

373
00:25:21,633 --> 00:25:25,133
SO, A VERY SHORT TIME,
VERY LARGE AMOUNT OF ENERGY,

374
00:25:25,133 --> 00:25:27,133
AND VERY DEVASTATING EFFECTS.

375
00:25:27,133 --> 00:25:31,200
Narrator:
THE ASTEROID IS OBLITERATED.

376
00:25:31,200 --> 00:25:35,100
A MIGHTY SHOCK WAVE
GENERATES WINDS

377
00:25:35,100 --> 00:25:39,567
SIX TIMES MORE POWERFUL
THAN A HURRICANE.

378
00:25:39,567 --> 00:25:42,100
Sykes: YOU HAVE THE BLAST
THAT COMES OUT,

379
00:25:42,100 --> 00:25:44,067
PROBABLY FOR SEVERAL MILES,

380
00:25:44,067 --> 00:25:48,767
AND LARGE DEBRIS THAT WOULD
CRUSH BUILDINGS AND HOMES.

381
00:25:48,767 --> 00:25:52,133
Narrator: IF IT HIT TODAY,

382
00:25:52,133 --> 00:25:58,767
THE ASTEROID FROM METEOR CRATER
WOULD BE A CITY KILLER.

383
00:25:58,767 --> 00:26:03,067
BUT THE METEOR CRATER ASTEROID
WAS SMALL.

384
00:26:03,067 --> 00:26:09,600
IT WAS LIKELY A FRAGMENT
FROM A MUCH LARGER ASTEROID.

385
00:26:09,600 --> 00:26:13,300
WHATEVER IT IS THAT HIT IN
METEOR CRATER WASN'T VERY BIG.

386
00:26:13,300 --> 00:26:15,400
IT WAS PROBABLY 50 YARDS ACROSS,

387
00:26:15,400 --> 00:26:18,100
SO NOT EVEN AS BIG
AS A FOOTBALL FIELD.

388
00:26:18,100 --> 00:26:24,133
Narrator: THERE ARE MILLIONS
OF MUCH LARGER ASTEROIDS.

389
00:26:24,133 --> 00:26:28,633
THESE WOULD CAUSE
EVEN MORE CARNAGE --

390
00:26:28,633 --> 00:26:31,600
COUNTRY KILLERS AND WORSE.

391
00:26:32,967 --> 00:26:36,433
ASTEROIDS OVER A HALF MILE WIDE

392
00:26:36,433 --> 00:26:39,733
COULD END OUR CIVILIZATION --

393
00:26:39,733 --> 00:26:43,100
WORLDWIDE KILLERS.

394
00:26:43,100 --> 00:26:46,733
WE KNOW BECAUSE
IT HAPPENED ALREADY.

395
00:26:51,267 --> 00:26:54,667
THERE ARE TRACES EVERYWHERE.

396
00:26:56,800 --> 00:26:59,867
Plait: THERE'S EVIDENCE OF GIANT
IMPACTS ALL OVER THE WORLD,

397
00:26:59,867 --> 00:27:02,233
AND IT'S RIGHT UNDERNEATH
YOUR FEET.

398
00:27:02,233 --> 00:27:05,467
AND IN FACT, IN SOME PLACES,
IT'S PRETTY EASY TO SPOT.

399
00:27:09,267 --> 00:27:13,800
Narrator:
LIKE HERE IN SOUTHERN COLORADO.

400
00:27:17,333 --> 00:27:22,100
SO, THIS LAYER OF LIGHT-COLORED
ROCK, THAT'S THE KT BOUNDARY.

401
00:27:22,100 --> 00:27:25,767
AND IT'S CALLED A BOUNDARY
BECAUSE IT MARKS THE BOUNDARY

402
00:27:25,767 --> 00:27:27,733
BETWEEN TWO DIFFERENT
TIME PERIODS.

403
00:27:27,733 --> 00:27:29,600
EVERYTHING THAT WAS
PUT DOWN HERE

404
00:27:29,600 --> 00:27:33,067
UNDERNEATH THE KT BOUNDARY
HAD DINOSAURS IN IT.

405
00:27:33,067 --> 00:27:35,733
EVERYTHING ABOVE IT --
NO DINOSAURS.

406
00:27:35,733 --> 00:27:38,500
SO IT REALLY MARKS
THAT POINT IN TIME

407
00:27:38,500 --> 00:27:40,567
WHEN THE DINOSAURS WENT AWAY.

408
00:27:40,567 --> 00:27:46,967
Narrator: THE LAYER IS RICH
IN AN ELEMENT CALLED IRIDIUM.

409
00:27:46,967 --> 00:27:53,333
IT'S RARE ON THE EARTH'S SURFACE
BUT COMMON IN ASTEROIDS.

410
00:27:53,333 --> 00:27:56,700
SO, IF A GIANT ASTEROID CAME IN,
SMACKED INTO THE EARTH,

411
00:27:56,700 --> 00:27:58,233
BLEW OUT DUST EVERYWHERE,

412
00:27:58,233 --> 00:28:00,167
THE IRIDIUM INSIDE THE ASTEROID

413
00:28:00,167 --> 00:28:03,200
WOULD'VE SETTLED DOWN
INTO A LAYER ALL OVER EARTH,

414
00:28:03,200 --> 00:28:05,633
AND THAT'S EXACTLY
WHAT WE SEE RIGHT HERE.

415
00:28:08,067 --> 00:28:12,067
Narrator: THE CLEAR FINGERPRINT
OF AN ASTEROID.

416
00:28:12,067 --> 00:28:14,800
Thaller: THERE MUST HAVE BEEN
SOME PERFECT MORNING

417
00:28:14,800 --> 00:28:16,267
BEFORE THE ASTEROID IMPACT

418
00:28:16,267 --> 00:28:18,967
WHEN THE LAND OF THE DINOSAURS
WAS STILL VERY MUCH

419
00:28:18,967 --> 00:28:21,067
AS IT HAD BEEN
FOR MILLIONS OF YEARS.

420
00:28:21,067 --> 00:28:23,833
THEN THERE WOULD BE SOMETHING
SIGHTED UP IN THE SKY,

421
00:28:23,833 --> 00:28:25,533
SOMETHING VERY BRIGHT, VERY HOT.

422
00:28:25,533 --> 00:28:29,700
Narrator: THE ASTEROID
IS SIX MILES LONG,

423
00:28:29,700 --> 00:28:33,367
BIG ENOUGH
TO DEVASTATE THE PLANET.

424
00:28:35,233 --> 00:28:38,233
THE ASTEROID THAT CAME IN
AND FORMED THIS LAYER HERE

425
00:28:38,233 --> 00:28:40,733
WAS VERY MASSIVE
AND WAS MOVING VERY FAST,

426
00:28:40,733 --> 00:28:42,833
AND SO WHEN IT IMPACTED
THE EARTH,

427
00:28:42,833 --> 00:28:46,133
THAT ENERGY WAS TURNED INTO
BOOM -- A VERY, VERY BIG BOOM.

428
00:28:49,300 --> 00:28:54,767
Narrator: IT HAS THE FORCE
OF 5 BILLION HIROSHIMA BOMBS.

429
00:28:54,767 --> 00:29:00,433
LARGE PIECES OF EARTH BLOW OUT
INTO SPACE,

430
00:29:00,433 --> 00:29:06,567
THEN RAIN BACK DOWN --
A STORM OF FIREBALLS.

431
00:29:06,567 --> 00:29:11,667
WILDFIRES RAGE ACROSS THE GLOBE.

432
00:29:15,700 --> 00:29:20,200
IN THE KT BOUNDARY LAYER
IS A LAYER OF SOOT,

433
00:29:20,200 --> 00:29:23,433
AND THAT'S AN INDICATION
THAT THERE WERE GLOBAL FIRES,

434
00:29:23,433 --> 00:29:26,267
THAT EVERYTHING ON EARTH
WAS BASICALLY ON FIRE

435
00:29:26,267 --> 00:29:27,567
AFTER THIS HAPPENED.

436
00:29:27,567 --> 00:29:33,633
Narrator: THE EARTH PLUNGES
INTO DARKNESS --

437
00:29:33,633 --> 00:29:37,467
AN IMPACT WINTER --

438
00:29:37,467 --> 00:29:39,300
MASS EXTINCTION.

439
00:29:39,300 --> 00:29:41,733
Durda: BASICALLY
YOU CAN THINK OF THIS

440
00:29:41,733 --> 00:29:44,067
AS EVERY ENVIRONMENTAL
CATASTROPHE

441
00:29:44,067 --> 00:29:45,867
ALL HAPPENING AT THE SAME TIME.

442
00:29:45,867 --> 00:29:48,733
IT WAS AN INCREDIBLY BAD DAY
FOR PLANET EARTH.

443
00:29:48,733 --> 00:29:54,967
Narrator: A CHILLING REMINDER
OF THE THREAT FROM SPACE.

444
00:29:54,967 --> 00:30:00,300
ASTEROIDS THIS BIG
WILL HIT US AGAIN.

445
00:30:00,300 --> 00:30:03,200
Schultz: WE WILL GO
THE WAY OF THE DINOSAURS.

446
00:30:03,200 --> 00:30:04,767
WE WILL BE SURVIVED,

447
00:30:04,767 --> 00:30:07,833
MOST LIKELY BY THE BUGS,
THE COCKROACHES.

448
00:30:07,833 --> 00:30:11,500
THEY WILL BE THE ONES
WHO WILL INHERIT THIS EARTH.

449
00:30:11,500 --> 00:30:13,933
BUT HOPEFULLY THAT'S GONNA BE
A LONG TIME FROM NOW.

450
00:30:13,933 --> 00:30:18,567
Narrator: IS MANKIND DOOMED?

451
00:30:18,567 --> 00:30:22,733
OR CAN WE DODGE FATE?

452
00:30:29,867 --> 00:30:35,300
Narrator:
ASTEROIDS BUILT OUR WORLD.

453
00:30:35,300 --> 00:30:38,667
THEY BROUGHT WATER.

454
00:30:38,667 --> 00:30:42,133
THEY KILLED THE DINOSAURS

455
00:30:42,133 --> 00:30:46,400
AND MADE ROOM FOR NEW SPECIES.

456
00:30:48,667 --> 00:30:52,533
BUT ASTEROIDS ARE ALSO A THREAT.

457
00:30:55,367 --> 00:30:57,533
Thaller: WE KNOW ABSOLUTELY
FOR CERTAIN

458
00:30:57,533 --> 00:31:00,067
THAT THERE WILL BE LARGE IMPACTS
IN THE FUTURE,

459
00:31:00,067 --> 00:31:03,533
SO IT'S NOT A QUESTION OF "IF,"
IT'S ONLY A QUESTION OF "WHEN."

460
00:31:03,533 --> 00:31:08,267
Krauss:
LARGE METEOR IMPACTS HAPPEN ONCE
EVERY 60 TO 100 MILLION YEARS.

461
00:31:08,267 --> 00:31:10,333
WE'RE DUE FOR ONE SOON PERHAPS.

462
00:31:10,333 --> 00:31:16,500
Narrator: IF WE WANT TO SURVIVE,
WE NEED TO PREPARE.

463
00:31:16,500 --> 00:31:19,933
WE MUST FIND THE ASTEROIDS,

464
00:31:19,933 --> 00:31:23,433
DETERMINE IF THEY'RE HEADING
FOR EARTH,

465
00:31:23,433 --> 00:31:25,767
THEN STOP THEM.

466
00:31:25,767 --> 00:31:28,533
THAT'S NOT EASY.

467
00:31:28,533 --> 00:31:31,067
BUT IT MAY BE POSSIBLE.

468
00:31:31,067 --> 00:31:34,500
HAPPILY, THERE'S A DIFFERENCE
BETWEEN US AND DINOSAURS.

469
00:31:34,500 --> 00:31:35,767
WE HAVE TELESCOPES,

470
00:31:35,767 --> 00:31:38,567
AND WE CAN GET ADVANCE NOTICE
OF AN IMPACT.

471
00:31:41,433 --> 00:31:46,633
Narrator: ASTEROIDS ARE MUCH
SMALLER THAN STARS AND PLANETS.

472
00:31:46,633 --> 00:31:48,867
IT'S HARD TO SEE THEM COMING.

473
00:31:51,067 --> 00:31:54,100
TO TRACK ASTEROIDS,

474
00:31:54,100 --> 00:31:58,067
YOU NEED A GIANT TELESCOPE

475
00:31:58,067 --> 00:32:03,267
LIKE THE ARECIBO OBSERVATORY
IN PUERTO RICO.

476
00:32:03,267 --> 00:32:06,833
RIGHT NOW I'M ON TOP OF THE
LARGEST TELESCOPE IN THE WORLD,

477
00:32:06,833 --> 00:32:09,067
AND THIS PLACE MAY ACTUALLY BE
OUR BEST DEFENSE

478
00:32:09,067 --> 00:32:11,667
AGAINST GETTING HIT BY ONE
OF THESE NEAR-EARTH ASTEROIDS.

479
00:32:11,667 --> 00:32:17,467
Narrator: THE VAST BOWL
IS 1,000 FEET ACROSS.

480
00:32:20,133 --> 00:32:23,533
AND IT'S NOT ONLY THE WORLD'S
BIGGEST TELESCOPE,

481
00:32:23,533 --> 00:32:28,067
IT'S ALSO THE WORLD'S
BIGGEST RADAR DISH.

482
00:32:28,067 --> 00:32:29,333
WHEN YOU THINK ABOUT USING RADAR

483
00:32:29,333 --> 00:32:30,800
TO KEEP TRACK
OF ALL THE AIRPLANES

484
00:32:30,800 --> 00:32:31,800
THAT ARE UP IN THE SKY,

485
00:32:31,800 --> 00:32:33,667
WELL, THIS ONE IS SO POWERFUL,

486
00:32:33,667 --> 00:32:37,600
IT CAN ACTUALLY TRACK NEAR-EARTH
OBJECTS MILLIONS OF MILES AWAY.

487
00:32:37,600 --> 00:32:40,833
Narrator:
UNLIKE A TELESCOPE,

488
00:32:40,833 --> 00:32:45,633
RADAR CAN DIRECTLY MEASURE
AN OBJECT'S DISTANCE

489
00:32:45,633 --> 00:32:48,700
AND REVEAL EXACTLY WHERE IT IS.

490
00:32:48,700 --> 00:32:53,567
THAT'S PERFECT
FOR TRACKING ASTEROIDS.

491
00:32:53,567 --> 00:32:56,300
IN 2004,

492
00:32:56,300 --> 00:33:00,567
ASTRONOMERS SPOT
A STADIUM-SIZED ASTEROID

493
00:33:00,567 --> 00:33:02,767
HEADING TOWARD EARTH.

494
00:33:02,767 --> 00:33:04,433
ITS NAME --

495
00:33:04,433 --> 00:33:09,667
"APOPHIS," AFTER THE EGYPTIAN
GOD OF DESTRUCTION.

496
00:33:11,233 --> 00:33:13,933
THE DAY IT MIGHT HIT US --

497
00:33:13,933 --> 00:33:18,067
APRIL 13, 2029,

498
00:33:18,067 --> 00:33:21,900
FRIDAY THE 13th.

499
00:33:21,900 --> 00:33:24,233
Thaller: APOPHIS WAS THE FIRST
NEAR-EARTH OBJECT

500
00:33:24,233 --> 00:33:26,833
OF THE MODERN ERA THAT HAD
ASTRONOMERS HONESTLY SCARED.

501
00:33:26,833 --> 00:33:28,700
THERE SEEMED TO BE
A ONE IN 30 CHANCE

502
00:33:28,700 --> 00:33:30,533
OF SOMETHING CATASTROPHIC
HAPPENING.

503
00:33:30,533 --> 00:33:34,500
Narrator:
ARECIBO SPRINGS INTO ACTION

504
00:33:34,500 --> 00:33:39,833
AGAINST THE BIGGEST THREAT
FROM SPACE EVER DETECTED.

505
00:33:39,833 --> 00:33:44,767
APOPHIS COULD DEVASTATE
ENTIRE COUNTRIES.

506
00:33:44,767 --> 00:33:49,300
BUT THE ASTEROID'S PATH
IS STILL UNCERTAIN.

507
00:33:49,300 --> 00:33:54,067
IT MIGHT HIT,
OR IT MIGHT JUST MISS.

508
00:33:54,067 --> 00:33:58,700
ONLY ARECIBO
CAN TELL US FOR SURE.

509
00:33:58,700 --> 00:34:00,500
Thaller:
THE ARECIBO TELESCOPE

510
00:34:00,500 --> 00:34:03,233
WAS ABLE TO REDUCE THE
UNCERTAINTY OF APOPHIS BY 98%.

511
00:34:03,233 --> 00:34:05,200
IT TOLD US THAT THERE WAS
NO CHANCE

512
00:34:05,200 --> 00:34:06,833
THIS THING WOULD HIT US IN 2029.

513
00:34:11,167 --> 00:34:14,267
Narrator: IT WILL BE CLOSE.

514
00:34:14,267 --> 00:34:20,133
APOPHIS WILL PASS CLOSER
TO THE EARTH THAN THE MOON,

515
00:34:20,133 --> 00:34:25,633
CLOSER EVEN THAN SOME
COMMUNICATIONS SATELLITES.

516
00:34:28,767 --> 00:34:34,767
WE HAVE POWERFUL TOOLS
TO DETECT ASTEROIDS.

517
00:34:34,767 --> 00:34:38,900
SOMEDAY, WE'LL FIND ONE
THAT WILL HIT THE EARTH.

518
00:34:40,100 --> 00:34:44,733
HOW CAN WE PROTECT OURSELVES?

519
00:34:44,733 --> 00:34:48,800
THE OBVIOUS STRATEGY
IS TO DESTROY THE ASTEROID

520
00:34:48,800 --> 00:34:50,767
BEFORE IT DESTROYS US.

521
00:34:50,767 --> 00:34:53,900
BUT THAT COULD BE RISKY.

522
00:34:53,900 --> 00:34:56,533
Schweickart:
YOU DON'T WANT TO BLOW IT UP

523
00:34:56,533 --> 00:34:58,833
BECAUSE YOU MAY END UP
BREAKING IT UP

524
00:34:58,833 --> 00:35:00,967
INTO TWO OR THREE
OR FIVE PIECES,

525
00:35:00,967 --> 00:35:03,700
WHICH THEN END UP HITTING
ALL AROUND THE EARTH

526
00:35:03,700 --> 00:35:06,867
AND WIPING OUT
MANY, MANY PEOPLE.

527
00:35:06,867 --> 00:35:12,533
Narrator: EXPLODING AN ASTEROID
COULD CAUSE MORE HARM THAN GOOD.

528
00:35:12,533 --> 00:35:16,467
BETTER TO MAKE IT
MISS COMPLETELY.

529
00:35:16,467 --> 00:35:19,767
WHEN AN ASTEROID IS HEADED
FOR EARTH,

530
00:35:19,767 --> 00:35:23,433
THEIR FUTURE PATHS CROSS.

531
00:35:23,433 --> 00:35:28,467
AND THEY'LL BOTH REACH
THAT POINT AT THE SAME TIME.

532
00:35:30,600 --> 00:35:34,300
IMAGINE THE EARTH
IS A FREIGHT TRAIN

533
00:35:34,300 --> 00:35:37,600
AND THE ASTEROID IS A CAR,

534
00:35:37,600 --> 00:35:41,800
BOTH HEADING
FOR A RAILROAD CROSSING.

535
00:35:41,800 --> 00:35:45,367
IF THEY REACH THAT CROSSING
AT THE SAME TIME,

536
00:35:45,367 --> 00:35:47,833
THEY WILL COLLIDE.

537
00:35:47,833 --> 00:35:50,767
THE BEST WAY TO AVOID THE IMPACT

538
00:35:50,767 --> 00:35:54,433
IS NOT TO SWERVE AWAY
FROM THE TRAIN,

539
00:35:54,433 --> 00:35:57,867
IT'S TO HIT THE GAS
OR THE BRAKES.

540
00:35:57,867 --> 00:36:01,400
Plait: IF YOU CAN CROSS THE TRACKS
BEFORE THE TRAIN GETS THERE

541
00:36:01,400 --> 00:36:04,233
OR WAIT FOR THE TRAIN TO PASS
AND THEN CROSS THEM --

542
00:36:04,233 --> 00:36:06,300
THAT'S WHAT WE WANT TO DO
WITH ASTEROIDS,

543
00:36:06,300 --> 00:36:08,700
JUST TO MAKE SURE THAT
THE ASTEROID AND THE EARTH

544
00:36:08,700 --> 00:36:10,833
AREN'T AT THE SAME PLACE
AT THE SAME TIME.

545
00:36:13,200 --> 00:36:16,067
[ TRAIN HORN BLOWS ]

546
00:36:18,100 --> 00:36:21,600
BY SIMPLY SLOWING DOWN THE CAR,
WE'RE GONNA MISS.

547
00:36:21,600 --> 00:36:24,300
THAT'S THE WAY TO AVERT
A COLLISION.

548
00:36:26,800 --> 00:36:31,467
Narrator: BUT ASTEROIDS
DON'T COME WITH BRAKES.

549
00:36:31,467 --> 00:36:35,733
WE NEED ANOTHER WAY
TO CHANGE THEIR SPEED.

550
00:36:35,733 --> 00:36:41,833
ONE APPROACH IS TO USE
THE ASTEROID'S GRAVITY.

551
00:36:41,833 --> 00:36:43,667
FOR A SMALL ENOUGH ASTEROID,

552
00:36:43,667 --> 00:36:46,567
ALL YOU NEED TO DO IS PARK
A LARGE SPACECRAFT

553
00:36:46,567 --> 00:36:48,167
NEXT TO THE ASTEROID.

554
00:36:48,167 --> 00:36:53,433
Narrator: A SPACESHIP WOULD HOVER
ABOVE THE ASTEROID'S SURFACE.

555
00:36:53,433 --> 00:36:55,467
YOU CAN THRUST
WITH YOUR SPACECRAFT

556
00:36:55,467 --> 00:36:58,567
TO KEEP IT FROM FALLING ONTO
THE SURFACE OF THE ASTEROID,

557
00:36:58,567 --> 00:37:00,933
AND SO IT'S LIKE A LITTLE
GRAVITY TRACTOR --

558
00:37:00,933 --> 00:37:02,667
USING GRAVITY AS THE TOW LINE

559
00:37:02,667 --> 00:37:04,767
TO MOVE THE ASTEROID
OUT OF THE WAY.

560
00:37:04,767 --> 00:37:08,433
Narrator: OVER TIME,
THE GRAVITY BETWEEN THEM

561
00:37:08,433 --> 00:37:11,800
WOULD SLOW DOWN THE ASTEROID
JUST ENOUGH

562
00:37:11,800 --> 00:37:13,833
FOR IT TO MISS THE EARTH.

563
00:37:16,200 --> 00:37:21,600
ASTEROIDS COULD SHAPE OUR FUTURE
IN ANOTHER WAY.

564
00:37:21,600 --> 00:37:25,300
WE COULD TURN THEM
FROM A DEADLY THREAT

565
00:37:25,300 --> 00:37:28,900
INTO A PRECIOUS RESOURCE.

566
00:37:42,300 --> 00:37:47,067
Narrator:
ASTEROIDS ARE A CREATIVE FORCE.

567
00:37:47,067 --> 00:37:49,233
THEY BUILD PLANETS.

568
00:37:49,233 --> 00:37:51,933
THEY BRING WATER.

569
00:37:51,933 --> 00:37:55,367
BUT THEY'RE ALSO DESTRUCTIVE.

570
00:37:55,367 --> 00:37:57,933
ASTEROIDS ARE BOTH A BOON
AND A THREAT.

571
00:37:57,933 --> 00:38:00,800
EARLY ON, THEY BRING
THE MATERIALS FOR LIFE.

572
00:38:00,800 --> 00:38:02,767
LATER ON, THEY CAN DESTROY LIFE.

573
00:38:02,767 --> 00:38:07,500
Narrator: ASTEROIDS BRING
VIOLENCE AND DEATH.

574
00:38:07,500 --> 00:38:11,533
BUT LIFE MAY NOT ALWAYS
BE IN DANGER.

575
00:38:11,533 --> 00:38:16,067
Krauss: ULTIMATELY, IF LIFE
BECOMES INTELLIGENT ENOUGH,

576
00:38:16,067 --> 00:38:17,233
IT CAN SEND OBJECTS OUT

577
00:38:17,233 --> 00:38:19,133
TO DEFLECT OR DESTROY
THE IMPENDING ASTEROIDS.

578
00:38:19,133 --> 00:38:25,633
Narrator: WE NOW HAVE THE
TECHNOLOGY TO DIVERT ASTEROIDS.

579
00:38:25,633 --> 00:38:30,433
THAT MEANS WE CAN TREAT THEM
NOT AS A THREAT

580
00:38:30,433 --> 00:38:32,600
BUT AN OPPORTUNITY.

581
00:38:32,600 --> 00:38:35,567
WE COULD MINE THEM.

582
00:38:35,567 --> 00:38:37,600
Durda: MANY OF THEM ARE
JUST RIPE FOR THE TAKING

583
00:38:37,600 --> 00:38:39,233
IN THESE WONDERFUL
MINERAL RESOURCES.

584
00:38:39,233 --> 00:38:40,800
AND SO THE ASTEROIDS,
IN SOME WAYS,

585
00:38:40,800 --> 00:38:42,400
ARE LITERALLY GOLD MINES
IN THE SKY.

586
00:38:42,400 --> 00:38:46,433
Narrator:
THEY'RE NOT JUST GOLD MINES.

587
00:38:46,433 --> 00:38:48,500
THEY'RE ZINC MINES,

588
00:38:48,500 --> 00:38:50,200
ALUMINUM MINES,

589
00:38:50,200 --> 00:38:52,767
PLATINUM MINES.

590
00:38:52,767 --> 00:38:56,867
JUST ONE AVERAGE-SIZED ASTEROID

591
00:38:56,867 --> 00:38:58,833
COULD CONTAIN MINERALS

592
00:38:58,833 --> 00:39:02,367
WORTH THOUSANDS OF BILLIONS
OF DOLLARS.

593
00:39:05,667 --> 00:39:10,767
BUT FIRST, WE HAVE TO REACH
THE ASTEROIDS.

594
00:39:14,067 --> 00:39:17,900
ON APRIL 15, 2010,

595
00:39:17,900 --> 00:39:22,233
PRESIDENT OBAMA
ANNOUNCED A NEW PLAN.

596
00:39:22,233 --> 00:39:24,100
President Obama: BY 2025,

597
00:39:24,100 --> 00:39:27,367
WE EXPECT NEW SPACECRAFT
DESIGNED FOR LONG JOURNEYS

598
00:39:27,367 --> 00:39:30,633
TO ALLOW US TO BEGIN THE FIRST
EVER CREWED MISSIONS

599
00:39:30,633 --> 00:39:32,667
BEYOND THE MOON INTO DEEP SPACE.

600
00:39:34,633 --> 00:39:37,833
WE'LL START BY SENDING
ASTRONAUTS TO AN ASTEROID

601
00:39:37,833 --> 00:39:39,667
FOR THE FIRST TIME IN HISTORY.

602
00:39:39,667 --> 00:39:41,167
[ APPLAUSE ]

603
00:39:41,167 --> 00:39:44,533
Narrator: IRONICALLY,

604
00:39:44,533 --> 00:39:46,900
THE EASIEST ASTEROIDS TO REACH

605
00:39:46,900 --> 00:39:50,367
ARE THE SAME ONES
THAT THREATEN THE EARTH.

606
00:39:50,367 --> 00:39:52,333
AS THEY PASS BY,

607
00:39:52,333 --> 00:39:57,567
A SPACESHIP COULD RENDEZVOUS
WITH THE ASTEROID.

608
00:39:57,567 --> 00:40:01,933
YET EVEN WHEN ASTEROIDS
COME SO CLOSE,

609
00:40:01,933 --> 00:40:06,800
ASTEROID MINING MAY BE TOO GOOD
TO BE TRUE.

610
00:40:06,800 --> 00:40:11,233
Kaku: THE REASON WHY WE'RE NOT
MINING THE ASTEROID BELT TODAY

611
00:40:11,233 --> 00:40:14,200
AND LETTING THE SPACE PROGRAM
PAY FOR ITSELF

612
00:40:14,200 --> 00:40:15,600
IS BECAUSE OF COST.

613
00:40:15,600 --> 00:40:19,167
IT TAKES AN ENORMOUS AMOUNT
OF ROCKET FUEL AND EXPERTISE

614
00:40:19,167 --> 00:40:22,067
TO BRING BACK AN ASTEROID
FROM OUTER SPACE.

615
00:40:22,067 --> 00:40:25,533
Narrator:
BUT PERHAPS WE DON'T NEED

616
00:40:25,533 --> 00:40:30,100
TO BRING THE MINERALS BACK
TO EARTH.

617
00:40:30,100 --> 00:40:34,067
WE COULD USE THE RESOURCES
OF ASTEROIDS

618
00:40:34,067 --> 00:40:37,600
TO BUILD SETTLEMENTS
OUT IN SPACE.

619
00:40:37,600 --> 00:40:40,867
Kaku: YOU DON'T HAVE TO BUILD
A SPACE STATION.

620
00:40:40,867 --> 00:40:42,300
IT'S ALREADY THERE.

621
00:40:42,300 --> 00:40:43,900
YOU DON'T NEED SHIELDING

622
00:40:43,900 --> 00:40:47,033
BECAUSE YOU CAN SIMPLY DRILL
RIGHT INTO THE SOIL

623
00:40:47,033 --> 00:40:49,700
AND USE THE ROCKY MATERIAL
AS SHIELDING

624
00:40:49,700 --> 00:40:52,333
AGAINST RADIATION
AND MICRO-METEORITES.

625
00:40:52,333 --> 00:40:53,633
SO, IN SOME SENSE,

626
00:40:53,633 --> 00:40:56,767
THINK OF AN ASTEROID
AS A READY-MADE SPACE STATION.

627
00:40:56,767 --> 00:41:02,233
Narrator: LOW GRAVITY MAKES IT
EASY TO COME AND GO.

628
00:41:02,233 --> 00:41:04,867
THERE'S PLENTY OF WATER,

629
00:41:04,867 --> 00:41:08,733
AND ALL THE CONSTRUCTION
MATERIALS

630
00:41:08,733 --> 00:41:12,067
THAT COLONIZERS COULD EVER NEED.

631
00:41:15,133 --> 00:41:19,167
Kaku: SO, ONE DAY, WHEN WE HAVE
COLONIES IN THE ASTEROID BELT,

632
00:41:19,167 --> 00:41:21,633
AND WE NEED
TO BUILD CITIES THERE,

633
00:41:21,633 --> 00:41:24,833
THAT'S WHERE WE'RE GONNA
FIND VALUABLE DEPOSITS

634
00:41:24,833 --> 00:41:27,500
OF METALS
IN THE ASTEROID BELT ITSELF.

635
00:41:27,500 --> 00:41:32,233
Narrator:
A VAST BAND OF CITIES IN SPACE

636
00:41:32,233 --> 00:41:35,600
STRUNG ACROSS A BILLION MILES.

637
00:41:36,767 --> 00:41:41,267
AND NOT JUST CITIES
BUT FACTORIES

638
00:41:41,267 --> 00:41:47,067
TO TURN METAL FROM THE ASTEROIDS
INTO SPACESHIPS.

639
00:41:47,067 --> 00:41:49,933
PERHAPS ASTEROIDS COULD ACTUALLY
PROVIDE THE METAL --

640
00:41:49,933 --> 00:41:52,467
THE REAL STRUCTURE --
TO BUILD OUR SPACECRAFT.

641
00:41:52,467 --> 00:41:55,067
SO SOMEWHERE UP THERE,
BETWEEN MARS AND JUPITER,

642
00:41:55,067 --> 00:41:57,800
THERE MAY BE THE MAKINGS
OF OUR FUTURE SPACESHIPS.

643
00:41:57,800 --> 00:42:00,733
ULTIMATELY, ASTEROIDS
MAY BE A STEPPING STONE

644
00:42:00,733 --> 00:42:04,167
BY WHICH WE CAN, ONE DAY,
LEAVE THE ENTIRE SOLAR SYSTEM.

645
00:42:05,900 --> 00:42:09,800
Narrator:
ASTEROIDS MADE THE EARTH.

646
00:42:09,800 --> 00:42:13,800
PERHAPS THEY EVEN
BROUGHT LIFE HERE.

647
00:42:13,800 --> 00:42:15,833
AND IN THE FUTURE,

648
00:42:15,833 --> 00:42:20,533
ASTEROIDS COULD HELP HUMANS
ESCAPE THE EARTH

649
00:42:20,533 --> 00:42:23,667
AND COLONIZE THE GALAXY.

650
00:42:25,167 --> 00:42:29,833
Sykes: SO, IN A WAY, ASTEROIDS
ARE DRAWING US OUT INTO SPACE,

651
00:42:29,833 --> 00:42:33,800
WHETHER TO PROTECT OURSELVES
OR TO EXPAND WHERE WE LIVE.

652
00:42:37,200 --> 00:42:42,133
Narrator: ADVANCED CIVILIZATIONS
ALL OVER THE UNIVERSE

653
00:42:42,133 --> 00:42:47,733
MAY USE ASTEROIDS AS
STEPPING STONES TO THE STARS.

654
00:42:50,633 --> 00:42:55,733
MANKIND MAY SOON ENTER THE AGE

655
00:42:55,733 --> 00:42:58,333
OF ASTEROIDS.