1 00:00:01,000 --> 00:00:03,000 . 2 00:00:02,000 --> 00:00:07,000 Downloaded from YTS.MX 3 00:00:03,080 --> 00:00:05,400 We are not that special. 4 00:00:05,480 --> 00:00:07,520 Every time we look at the universe, 5 00:00:07,600 --> 00:00:10,440 we learn there is much more out there than we thought. 6 00:00:08,000 --> 00:00:13,000 Official YIFY movies site: YTS.MX 7 00:00:10,520 --> 00:00:13,760 The Hubble Telescope can only see what you can see with your eye. 8 00:00:13,840 --> 00:00:15,840 The James Webb Telescope looks at areas 9 00:00:15,920 --> 00:00:18,320 that the Hubble could never see. 10 00:00:18,400 --> 00:00:20,600 Another Earth is undoubtedly out there. 11 00:00:21,520 --> 00:00:24,320 It's inevitable that we have to leave our home. 12 00:00:24,400 --> 00:00:26,000 But where do we go? 13 00:00:27,040 --> 00:00:28,680 Whenever you go into the unknown, 14 00:00:28,760 --> 00:00:30,680 you discover things you didn't expect. 15 00:00:32,280 --> 00:00:35,440 I think that we are going to answer whether or not there is life 16 00:00:35,520 --> 00:00:37,760 on another planet in our lifetime. 17 00:00:38,320 --> 00:00:39,520 It's within our grasp 18 00:00:39,600 --> 00:00:42,040 to make a discovery that will change the world. 19 00:00:54,200 --> 00:00:57,480 As a boy, I was transfixed by a view of the moon 20 00:00:57,560 --> 00:00:59,560 through a neighbour's telescope. 21 00:01:01,800 --> 00:01:05,280 There was so much more to the world than could be seen with my naked eye. 22 00:01:09,040 --> 00:01:12,400 For the past 400 years, telescopes have transformed 23 00:01:12,480 --> 00:01:15,240 our vision of the universe again and again. 24 00:01:18,880 --> 00:01:21,960 Each era sees deeper and further than the one before it. 25 00:01:26,080 --> 00:01:29,280 The Hubble Space Telescope revealed more galaxies 26 00:01:29,360 --> 00:01:31,520 than we ever imagined existed. 27 00:01:33,440 --> 00:01:35,800 It gave us a sense of where we came from. 28 00:01:37,360 --> 00:01:40,240 And also, where we are going. 29 00:01:41,560 --> 00:01:44,520 We are on the verge of answering questions that have haunted us 30 00:01:44,600 --> 00:01:47,280 since the time of the ancient Greeks. 31 00:01:48,720 --> 00:01:50,840 Are we alone in the universe? 32 00:01:52,720 --> 00:01:56,080 Is there another Earth-like planet out there among the stars? 33 00:01:57,720 --> 00:02:01,200 To answer these questions, we need new telescopes. 34 00:02:01,280 --> 00:02:03,400 Bigger telescopes. 35 00:02:06,520 --> 00:02:08,720 Who better to tell me the story of telescopes 36 00:02:08,800 --> 00:02:12,520 than the people working on the most powerful instrument ever built? 37 00:02:13,240 --> 00:02:15,840 The James Webb Space Telescope. 38 00:02:21,560 --> 00:02:24,160 We'll see the first galaxies, the first stars. 39 00:02:25,960 --> 00:02:28,360 If we're really lucky, it's going to find 40 00:02:28,440 --> 00:02:31,120 the first evidence of liquid water, 41 00:02:31,200 --> 00:02:33,400 which is the first thing we need for life. 42 00:02:34,760 --> 00:02:37,520 We are on the verge of having the technological capability 43 00:02:37,600 --> 00:02:40,160 to find another Earth. 44 00:02:40,240 --> 00:02:44,760 It's going to seek deeper into space than any other telescope in history. 45 00:02:46,160 --> 00:02:48,720 The James Webb Space Telescope is not just a machine. 46 00:02:49,360 --> 00:02:51,360 It's taking humanity on a journey. 47 00:03:03,800 --> 00:03:05,920 So, as the ancients looked up at the sky, 48 00:03:06,000 --> 00:03:09,360 it was obvious that everything went around us. 49 00:03:11,400 --> 00:03:14,320 We see the sunrise in the east, and set in the west. 50 00:03:17,440 --> 00:03:19,520 We see the moon go across the sky. 51 00:03:19,600 --> 00:03:23,960 We were centred, we were the centre of the universe. 52 00:03:25,520 --> 00:03:29,200 The problem was, that model got a little complicated. 53 00:03:30,400 --> 00:03:32,760 If you observe the planets over weeks and months, 54 00:03:32,840 --> 00:03:35,200 they were making little loops. 55 00:03:35,280 --> 00:03:38,120 They weren't just going round in beautiful arcs, 56 00:03:38,200 --> 00:03:40,680 they were doing little loops. 57 00:03:43,040 --> 00:03:47,280 The model became more and more complicated. 58 00:03:48,520 --> 00:03:51,040 But it had us at the centre of our universe. 59 00:03:57,720 --> 00:03:59,800 Then Copernicus comes along, and said, 60 00:03:59,880 --> 00:04:01,960 'This is a really complicated model. 61 00:04:02,040 --> 00:04:05,640 You know, it's much simpler if we put the sun in the middle.' 62 00:04:06,640 --> 00:04:10,880 Born in 1473, mathematician, Nicolaus Copernicus, 63 00:04:10,960 --> 00:04:13,120 had no way to prove his theory, 64 00:04:13,200 --> 00:04:15,840 because he had no way to make the observation. 65 00:04:19,880 --> 00:04:22,640 Afraid of clashing with the church, and other astronomers, 66 00:04:22,720 --> 00:04:26,040 he didn't publish his theory until the year he died. 67 00:04:27,840 --> 00:04:32,040 50 years later, in 1609, an Italian scientist hears about 68 00:04:32,120 --> 00:04:36,080 a Dutch invention, that makes objects appear closer. 69 00:04:37,040 --> 00:04:40,240 Within a day, Galileo builds his own telescope. 70 00:04:41,200 --> 00:04:43,360 So, Galileo looks at the moon. 71 00:04:43,440 --> 00:04:45,600 The moon was supposed to be this perfect orb. 72 00:04:46,360 --> 00:04:49,200 And he sees for the first time, the moon is not perfect. 73 00:04:49,280 --> 00:04:51,520 It has mountains. It has craters. 74 00:04:52,440 --> 00:04:54,480 He sees the Milky Way. 75 00:04:54,560 --> 00:04:57,480 The Milky Way is not just this cloud, 76 00:04:57,560 --> 00:04:59,600 made up of individual stars. 77 00:05:00,760 --> 00:05:05,520 The most important observation, the one that was truly revolutionary, 78 00:05:05,600 --> 00:05:08,040 he looked at Jupiter. 79 00:05:10,440 --> 00:05:14,920 And he saw four pinpricks of light. And he assumed they were stars. 80 00:05:16,400 --> 00:05:18,960 Went back the next night, and saw there were only three, 81 00:05:19,040 --> 00:05:22,480 and they've moved. The next night, they moved again. 82 00:05:23,960 --> 00:05:27,280 Every night, the pinpricks are changing. 83 00:05:29,920 --> 00:05:33,080 And then he realised, that these were not stars, 84 00:05:33,160 --> 00:05:36,400 they were moons going around Jupiter. 85 00:05:37,960 --> 00:05:40,800 Everything was supposed to be going around the Earth. 86 00:05:40,880 --> 00:05:43,160 And here was proof that it wasn't. 87 00:05:45,120 --> 00:05:48,520 And he realises the ancients were wrong. The church was wrong. 88 00:05:48,600 --> 00:05:50,640 Copernicus was right. 89 00:05:51,560 --> 00:05:55,440 The whole world collapses into this beautiful simplicity. 90 00:05:56,480 --> 00:05:58,960 And we're going around the sun. 91 00:06:02,280 --> 00:06:04,920 A telescope really is quite simple. 92 00:06:06,040 --> 00:06:09,320 If you take this lens here, and the light comes in this way, 93 00:06:09,400 --> 00:06:12,480 and you take a second lens here, you have a telescope. 94 00:06:14,040 --> 00:06:17,160 That simple device, just these two lenses. That's all it took. 95 00:06:17,800 --> 00:06:20,560 That idea changed the world. 96 00:06:25,600 --> 00:06:28,800 The Webb Telescope is 100 times more powerful than Hubble. 97 00:06:29,960 --> 00:06:33,200 The mirrors are so perfect, that if you imagine spreading 98 00:06:33,280 --> 00:06:35,880 that mirror out from New York to California, 99 00:06:35,960 --> 00:06:38,600 there would be no deviation, no Hiller Valley 100 00:06:38,680 --> 00:06:41,000 across it more than three inches. 101 00:06:43,480 --> 00:06:47,560 Galileo's telescope gathered 100 times more light than the human eye. 102 00:06:49,440 --> 00:06:52,160 I'm told the James Webb Space Telescope will gather 103 00:06:52,240 --> 00:06:54,440 a million times more than the human eye. 104 00:06:55,720 --> 00:06:59,240 To gather its light however, Webb doesn't use Galileo's lenses, 105 00:06:59,320 --> 00:07:02,400 but the technique of a different genius. 106 00:07:03,520 --> 00:07:06,280 By the time he was 26, in 1668, 107 00:07:07,200 --> 00:07:11,320 Isaac Newton had invented calculus, and the law of gravitation. 108 00:07:11,400 --> 00:07:15,920 He'd also devised a new kind of telescope. The reflector. 109 00:07:16,000 --> 00:07:21,400 Newton pointed out that if you used a mirror, not a lens, 110 00:07:21,480 --> 00:07:24,680 all the wavelengths get reflected off the mirror 111 00:07:24,760 --> 00:07:27,800 in exactly the same way. So all those colours would come through, 112 00:07:27,880 --> 00:07:31,320 and they would all come to exactly the same perfect focus. 113 00:07:31,720 --> 00:07:35,400 And allowed us in the end, to make bigger and bigger telescopes. 114 00:07:35,840 --> 00:07:39,400 Able to collect more and more light, and see further and further 115 00:07:39,480 --> 00:07:41,640 and further into the universe. 116 00:07:41,720 --> 00:07:44,400 Ever since, the most powerful telescopes 117 00:07:44,480 --> 00:07:46,400 have used this basic design. 118 00:07:47,560 --> 00:07:51,920 The great Palomar 200 inch. The Keck 10 metre telescope. 119 00:07:53,560 --> 00:07:56,120 Hubble Space Telescope. 120 00:07:57,760 --> 00:08:01,000 The James Webb Space Telescope. All reflecting telescopes. 121 00:08:02,360 --> 00:08:05,440 If you showed the James Webb Space Telescope to Newton, 122 00:08:05,520 --> 00:08:07,280 he would recognise it as a telescope. 123 00:08:07,360 --> 00:08:09,520 Might be a bit surprised we're flying in space, 124 00:08:09,600 --> 00:08:12,040 but they would recognise it's a classic telescope. 125 00:08:20,640 --> 00:08:23,200 Someone telling us where to stop? 126 00:08:23,280 --> 00:08:26,760 Slow down. Slow down. Slow down. Whoa. 127 00:08:26,840 --> 00:08:28,880 When people think about the telescope, 128 00:08:28,960 --> 00:08:30,920 they think of the huge mirror, right. 129 00:08:31,000 --> 00:08:32,960 That's the iconic part of the telescope. 130 00:08:33,040 --> 00:08:35,600 This is what the astronomers care about. 131 00:08:36,680 --> 00:08:40,640 This is where the data comes from. The detectors and the cameras. 132 00:08:40,720 --> 00:08:44,440 All the images of the spectra, all the good stuff. 133 00:08:46,400 --> 00:08:48,160 It will come from there. 134 00:08:48,240 --> 00:08:50,560 It's $1 billion worth of hardware in there. 135 00:08:52,400 --> 00:08:54,920 We have enough sensitivity with our telescope 136 00:08:55,000 --> 00:08:58,800 and our instruments to detect a child's nightlight... 137 00:09:00,080 --> 00:09:02,520 ..from the moon. 138 00:09:11,640 --> 00:09:16,240 You could see things on the order of a candle, a match, a lit cigarette. 139 00:09:16,320 --> 00:09:19,200 I know that if you were to certainly take your radiant heat, 140 00:09:19,280 --> 00:09:23,000 which for a human, is about 80-100 watts, 141 00:09:23,080 --> 00:09:25,200 we would easily be able to detect that. 142 00:09:36,600 --> 00:09:39,240 The James Webb Space Telescope will be able to see 143 00:09:39,320 --> 00:09:41,520 the earliest galaxies in the universe. 144 00:09:41,600 --> 00:09:44,200 But not so long ago, we didn't know there were 145 00:09:44,280 --> 00:09:47,360 any galaxies out there other than our own. 146 00:09:47,440 --> 00:09:49,920 The Milky Way. 147 00:09:53,240 --> 00:09:56,000 Throughout the 18th and 19th centuries, 148 00:09:56,080 --> 00:10:00,320 most astronomers believed the Milky Way was the entire universe. 149 00:10:00,400 --> 00:10:03,280 But there were some strange, fuzzy objects out there, 150 00:10:03,360 --> 00:10:05,760 that were quite puzzling. 151 00:10:05,840 --> 00:10:09,240 They made countless drawings of these objects, and built bigger 152 00:10:09,320 --> 00:10:12,680 and bigger telescopes, trying to figure out what they were. 153 00:10:12,760 --> 00:10:14,760 If they were outside the Milky Way, 154 00:10:14,840 --> 00:10:18,240 it would mean the universe was a lot bigger than we thought. 155 00:10:19,080 --> 00:10:22,040 At that time, there was a Great Debate in astronomy. 156 00:10:22,120 --> 00:10:25,520 You could Google the word 'Great Debate', you'll think it might be 157 00:10:25,600 --> 00:10:28,920 some Supreme Court case, or some other important historical argument. 158 00:10:29,000 --> 00:10:31,000 But, no, the No.1 hit for Great Debate 159 00:10:31,080 --> 00:10:34,400 is the debate between two astronomers, trying to resolve 160 00:10:34,480 --> 00:10:36,400 what our place in the universe is. 161 00:10:37,480 --> 00:10:40,320 And they couldn't decide. Because they had no evidence. 162 00:10:40,400 --> 00:10:42,200 They couldn't see what was happening. 163 00:10:43,840 --> 00:10:46,040 Settling the Great Debate would require 164 00:10:46,120 --> 00:10:49,160 the biggest telescope yet attempted. 165 00:10:49,240 --> 00:10:53,360 And four and a half tons of smashed French wine bottles. 166 00:11:09,040 --> 00:11:13,200 The mirror for the Webb Telescope is so big we need to fold it up. 167 00:11:14,120 --> 00:11:17,640 What we need to do is basically slice it up into smaller segments, 168 00:11:17,720 --> 00:11:20,040 so we can fold it up, and unfold it on orbit. 169 00:11:20,120 --> 00:11:22,920 We wouldn't build a telescope this big unless we needed to. 170 00:11:23,000 --> 00:11:25,200 You need a telescope this big if you want to look 171 00:11:25,280 --> 00:11:28,520 at the very dimmest, earliest galaxies in the universe. 172 00:11:30,680 --> 00:11:33,640 When the 18 mirror segments are finally mounted 173 00:11:33,720 --> 00:11:35,520 on the carbon fibre backplate, 174 00:11:35,600 --> 00:11:40,240 they will all work together to create a near perfect optical surface, 175 00:11:40,320 --> 00:11:41,920 over 21 feet across. 176 00:11:44,720 --> 00:11:47,080 100 years ago, at the time of the Great Debate, 177 00:11:47,160 --> 00:11:50,520 it was a struggle to make a mirror just eight feet across. 178 00:11:51,920 --> 00:11:56,960 In 1908, the Saint-Gobain Glass Factory cast a 100-inch mirror 179 00:11:57,040 --> 00:12:00,600 out of four-and-a-half tonnes of bottle glass. 180 00:12:00,680 --> 00:12:04,760 The largest ever attempted. The mirror was full of bubbles. 181 00:12:05,280 --> 00:12:09,080 But it was shipped to California anyway, where an American, 182 00:12:09,160 --> 00:12:11,960 George Ellery Hale, was raising millions 183 00:12:12,040 --> 00:12:16,440 to build a new observatory on Mount Wilson, overlooking Los Angeles. 184 00:12:18,840 --> 00:12:21,840 The master polisher complained bitterly, 185 00:12:21,920 --> 00:12:24,720 but the mirror proved good enough to revolutionise 186 00:12:24,800 --> 00:12:26,800 our conception of the universe. 187 00:12:26,880 --> 00:12:30,800 And would force Albert Einstein to revise his equations. 188 00:12:32,520 --> 00:12:36,360 Despite promising his dying father he would become a lawyer, 189 00:12:36,440 --> 00:12:39,160 when Edwin Hubble was discharged from the army, 190 00:12:39,240 --> 00:12:41,440 after World War I, he went to Mount Wilson, 191 00:12:41,520 --> 00:12:43,920 and spent his time looking at the night sky. 192 00:12:45,160 --> 00:12:47,920 Four years later in October 1923, 193 00:12:48,120 --> 00:12:50,240 something caught his eye. 194 00:12:57,520 --> 00:13:00,560 Edwin Hubble began using the 100-inch telescope, 195 00:13:00,640 --> 00:13:02,920 the most powerful telescope of its time. 196 00:13:05,040 --> 00:13:08,800 He goes out, night after night, and takes photographic plates. 197 00:13:09,840 --> 00:13:14,120 One star in particular is changing its brightness about every month. 198 00:13:14,200 --> 00:13:16,680 He's comparing one photographic plate to another. 199 00:13:16,760 --> 00:13:19,000 Everything else is more or less staying the same, 200 00:13:19,080 --> 00:13:22,040 except this one beacon is blinking. 201 00:13:22,400 --> 00:13:27,080 And that blinking is a message to him. 202 00:13:27,160 --> 00:13:29,240 And so, he writes, 'VAR! 203 00:13:29,320 --> 00:13:31,400 'I don't want to lose this spot. 204 00:13:31,480 --> 00:13:35,320 'There is this sea of 100 billion dots, this one's special.' 205 00:13:37,640 --> 00:13:40,680 If you know the brightness of an object when it's nearby, 206 00:13:40,760 --> 00:13:43,480 you can figure out the distance to a similar object, 207 00:13:43,560 --> 00:13:45,200 by measuring how much dimmer it is. 208 00:13:46,240 --> 00:13:49,760 That's what Hubbell did with the Variable Star in Andromeda. 209 00:13:50,800 --> 00:13:53,720 He discovered Andromeda couldn't be part of the Milky Way. 210 00:13:54,360 --> 00:13:57,200 It was, in fact, two-and-a-half million light-years away. 211 00:13:58,840 --> 00:14:03,000 It had to be a totally separate galaxy. An island universe. 212 00:14:04,640 --> 00:14:07,200 It turns out the great challenge in astronomy 213 00:14:07,280 --> 00:14:09,960 is just figuring out how far away everything is. 214 00:14:10,040 --> 00:14:13,600 We see these things with the telescope, but how far are they? 215 00:14:13,680 --> 00:14:17,760 Getting that third dimension, the depth dimension, is so critical. 216 00:14:18,240 --> 00:14:22,800 And for the first time, we have enough depth perception to see, 217 00:14:22,880 --> 00:14:25,840 'Oh, the spiral nebulae, they're outside the Milky Way.' 218 00:14:29,000 --> 00:14:32,640 Hubble looks at one star - Variable 1, 219 00:14:32,800 --> 00:14:37,080 and immediately answers this profound question. 220 00:14:37,160 --> 00:14:42,440 Are we the only galaxy? Or is the universe teeming with them? 221 00:14:42,520 --> 00:14:47,640 I would say, next to the sun, it's my favourite star in the universe. 222 00:14:53,160 --> 00:14:57,920 Ultimately, there was no way to comprehend just how vast space was. 223 00:14:58,920 --> 00:15:01,520 It really did blow people's mind, 224 00:15:01,600 --> 00:15:04,000 when we started to be able to calculate the distances 225 00:15:04,080 --> 00:15:08,920 that we're talking about. Astronomical distances. 226 00:15:10,280 --> 00:15:13,240 And so they resolved the Great Debate in astronomy. 227 00:15:13,800 --> 00:15:17,040 And the scale of the universe is just dramatically increased. 228 00:15:17,800 --> 00:15:21,840 The history of telescopes is to teach us we're not that special. 229 00:15:21,920 --> 00:15:25,640 It makes us less and less special every time we look at the universe, 230 00:15:25,760 --> 00:15:28,800 and we learn there is much more out there than we thought before. 231 00:15:30,160 --> 00:15:33,520 And then Hubble showed us that the universe 232 00:15:33,600 --> 00:15:37,640 was also expanding. That was an incredible thought. 233 00:15:37,720 --> 00:15:40,640 Because Einstein had told us it wasn't. 234 00:15:44,480 --> 00:15:46,640 He felt the universe couldn't be expanding, 235 00:15:46,720 --> 00:15:49,480 and readjusted his equations to make it static. 236 00:15:49,560 --> 00:15:53,040 Edwin Hubble showed that the galaxies in fact, were flying apart. 237 00:15:53,960 --> 00:15:57,200 So, Einstein, as he admitted, this is his biggest blunder ever. 238 00:16:00,000 --> 00:16:02,640 The expanding universe was a revelation, 239 00:16:02,720 --> 00:16:04,920 because it implied an earlier time 240 00:16:05,000 --> 00:16:07,240 when all the galaxies were closer together. 241 00:16:07,720 --> 00:16:10,640 It implied a big bang. 242 00:16:16,200 --> 00:16:19,320 Edwin Hubble made that discovery when he first had access 243 00:16:19,400 --> 00:16:21,600 to the biggest telescope in the world. 244 00:16:22,640 --> 00:16:26,240 So, the obvious thing to do was to build a 200-inch telescope. 245 00:16:30,760 --> 00:16:36,200 The Palomar Mirror weighed roughly 14 tonnes, which is huge. 246 00:16:36,280 --> 00:16:38,920 The largest piece of mirror ever made. 247 00:16:41,120 --> 00:16:44,600 Palomar became the ultimate observing machine. 248 00:16:44,880 --> 00:16:46,680 And they called it The Big Eye. 249 00:16:55,600 --> 00:16:58,520 But this amazing machine, that nobody could think 250 00:16:58,600 --> 00:17:02,040 of how to make it any better, had one fundamental problem. 251 00:17:03,600 --> 00:17:05,960 It was sitting here on Earth. 252 00:17:08,720 --> 00:17:11,120 You know, you'll only hear an astronomer say this, 253 00:17:11,200 --> 00:17:13,360 but the air that we breathe, right, it sucks. 254 00:17:13,440 --> 00:17:16,760 We want to get rid of it. Because the air makes the images 255 00:17:16,920 --> 00:17:18,840 from stars that we're observing blurry. 256 00:17:19,920 --> 00:17:23,640 So, Lyman Spitzer suggested taking a giant telescope, 257 00:17:23,720 --> 00:17:25,960 and putting it in space. 258 00:17:26,040 --> 00:17:31,560 Above the atmosphere of the Earth. He proposed space telescopes. 259 00:17:31,640 --> 00:17:35,000 1948. We hadn't even successfully got rockets working. 260 00:17:35,080 --> 00:17:37,600 So, it was an incredibly imaginative leap. 261 00:17:39,160 --> 00:17:43,120 It would take more than 40 years, but Lyman Spitzer's dream 262 00:17:43,200 --> 00:17:45,360 of an astronomical telescope in space 263 00:17:45,440 --> 00:17:49,920 finally came true on April 24th, 1990. 264 00:18:06,320 --> 00:18:09,200 We finally got our space telescope. It was put on the shuttle. 265 00:18:09,280 --> 00:18:11,480 It was launched into orbit. 266 00:18:12,520 --> 00:18:15,600 Everybody waits for the first results to come down. 267 00:18:16,920 --> 00:18:19,160 There is big trouble with the $2 billion 268 00:18:19,240 --> 00:18:21,160 Hubble Space Telescope tonight. 269 00:18:21,400 --> 00:18:24,720 Grim-faced officials had to reveal that the photo system 270 00:18:24,800 --> 00:18:27,280 on board the Hubble telescope is sick. 271 00:18:27,360 --> 00:18:29,440 But Hubble doesn't focus properly. 272 00:18:29,520 --> 00:18:31,720 One of the mirrors on the Hubble Space Telescope 273 00:18:31,800 --> 00:18:33,840 was designed to the wrong specifications. 274 00:18:33,920 --> 00:18:38,880 The images were blurry. The mirror was fatally flawed. 275 00:18:38,960 --> 00:18:42,920 We'd blown billions of dollars on a flawed space telescope. 276 00:18:43,720 --> 00:18:46,400 At the edge of this 94-inch mirror, 277 00:18:47,280 --> 00:18:50,760 the mirror was off by a fraction of the width of a human hair. 278 00:18:50,840 --> 00:18:52,920 That's all it took. 279 00:18:53,720 --> 00:18:56,640 Fortunately, Hubble's only eight minutes away. 280 00:18:57,880 --> 00:19:00,800 It only takes the shuttle eight minutes to get to the orbit. 281 00:19:01,600 --> 00:19:03,640 And so, you can go fix it. 282 00:19:03,720 --> 00:19:06,920 And in fact, astronauts went back several times, to do so. 283 00:19:07,960 --> 00:19:12,240 At one point, Story Musgrave and Jeff Hoffman had to close the doors. 284 00:19:12,320 --> 00:19:16,200 And they wouldn't close. They ended up taking one of these come-a-longs, 285 00:19:16,280 --> 00:19:19,760 one of those straps that you crank. And they tried to crank it together. 286 00:19:19,840 --> 00:19:22,440 They could have broken Hubble. If those doors had broken, 287 00:19:22,520 --> 00:19:24,880 that would've been the end of Hubble, right there. 288 00:19:24,960 --> 00:19:27,600 But fortunately they sort of locked into place. 289 00:19:27,680 --> 00:19:30,440 When those first images came down, 290 00:19:30,520 --> 00:19:33,680 they were better than we could have even imagined. 291 00:19:35,600 --> 00:19:39,320 And that started Hubble's journey to change the world. 292 00:19:48,080 --> 00:19:50,680 Witnessing the births and death of stars. 293 00:19:52,480 --> 00:19:55,720 Finding black holes at the centre of galaxies. 294 00:19:55,800 --> 00:19:58,080 Measuring the age of the universe. 295 00:20:00,160 --> 00:20:02,960 Confirming the existence of dark energy. 296 00:20:04,120 --> 00:20:06,800 What is Hubble's greatest achievement? 297 00:20:06,880 --> 00:20:08,880 Ask that in a room full of astronomers, 298 00:20:08,960 --> 00:20:11,160 and you'll start another great debate. 299 00:20:11,960 --> 00:20:16,040 But everyone agrees, Hubble is one of the greatest scientific instruments 300 00:20:16,120 --> 00:20:19,000 in history. 301 00:20:19,080 --> 00:20:22,520 The Hubble Space Telescope is the Holy Grail for astronauts, 302 00:20:22,600 --> 00:20:25,040 but especially for astronomers. 303 00:20:26,600 --> 00:20:29,440 I spent three of my five space shuttle missions going to 304 00:20:29,520 --> 00:20:32,280 the Hubble Space Telescope. In fact, the last three. 305 00:20:33,760 --> 00:20:36,560 And at the end of the last space walk, I gave it a pat, 306 00:20:36,640 --> 00:20:40,000 and a little salute, and said, 'Good luck, Mr Hubble.' 307 00:20:40,080 --> 00:20:42,960 Because I knew I would never see it again. 308 00:20:43,040 --> 00:20:46,920 Are there images from Hubble that mean a lot to you? 309 00:20:47,000 --> 00:20:49,680 Personally, do you have a favourite? 310 00:20:49,760 --> 00:20:51,960 I've lots of favourite images. 311 00:20:52,760 --> 00:20:55,680 My favourite images are the first images that come back 312 00:20:55,760 --> 00:20:58,040 after the missions I had gone to do the servicing, 313 00:20:58,120 --> 00:21:00,280 to prove I didn't break the Hubble. 314 00:21:02,120 --> 00:21:04,280 For me, Hubble's most awe-inspiring image 315 00:21:04,360 --> 00:21:07,040 is a long-time exposure, 316 00:21:07,120 --> 00:21:09,160 known as the Deep Field. 317 00:21:11,200 --> 00:21:13,760 Hubble Deep Field was a pure discovery. 318 00:21:15,920 --> 00:21:19,440 It was, 'We don't know what's there, let's see if we can see something.' 319 00:21:20,560 --> 00:21:23,640 The second director of the Hubble Space Telescope said, 'You know, 320 00:21:23,720 --> 00:21:26,240 Hubble is looking deeper and deeper in the universe. 321 00:21:26,320 --> 00:21:28,360 I wonder what happens if we just stared 322 00:21:28,440 --> 00:21:32,120 at a completely blank piece of sky? Just see what we find.' 323 00:21:33,120 --> 00:21:35,320 And so, he decided to point the telescope 324 00:21:35,400 --> 00:21:38,720 at a single blank piece of sky, no bigger than a drinking straw. 325 00:21:41,400 --> 00:21:43,560 That's the area of the sky he decided to look at 326 00:21:43,640 --> 00:21:46,880 with the Hubble Space Telescope. And just stare at 327 00:21:46,960 --> 00:21:49,320 that single, blank spot, for ten days. 328 00:21:49,400 --> 00:21:51,880 And see what would happen. 329 00:21:51,960 --> 00:21:55,280 A lot of people said he was crazy, he was wasting telescope time. 330 00:21:55,960 --> 00:21:57,880 But the telescope oriented, 331 00:21:57,960 --> 00:22:00,760 and stared at that one spot for like ten days, 332 00:22:00,840 --> 00:22:03,400 with our most sensitive cameras at the time. 333 00:22:05,240 --> 00:22:08,200 And to everybody's surprise, when they looked at the image, 334 00:22:08,280 --> 00:22:13,480 out of that dark area of the sky 335 00:22:13,560 --> 00:22:16,680 came 10,000 galaxies in that single point of sky. 336 00:22:22,760 --> 00:22:25,120 Nobody had any idea there was this many galaxies 337 00:22:25,200 --> 00:22:27,880 in the observable universe. 338 00:22:30,360 --> 00:22:32,320 You look at the Hubble Deep Field, 339 00:22:32,400 --> 00:22:35,920 only three of those points of light are stars. 340 00:22:36,000 --> 00:22:40,400 Every other point of light in that image is a galaxy. 341 00:22:44,440 --> 00:22:47,240 So, there are 10,000 galaxies in every spot of the sky 342 00:22:47,320 --> 00:22:49,600 the size of a drinking straw. 343 00:22:54,160 --> 00:22:57,040 Roughly a hundred billion stars in the galaxy. 344 00:22:57,320 --> 00:23:02,880 If you do the maths across the whole sky, it's 10 to the 22 stars 345 00:23:02,960 --> 00:23:04,960 in the observable galaxies. 346 00:23:05,040 --> 00:23:07,600 And I'm not going to work out how many, what that is, 347 00:23:07,680 --> 00:23:10,240 but it's 10 with 22 zeros. 348 00:23:13,920 --> 00:23:17,760 The Deep Field marks the limit of what Hubble can see. 349 00:23:17,840 --> 00:23:20,200 To complete the picture of galaxies 350 00:23:20,280 --> 00:23:23,120 in the universe, we need a new kind telescope. 351 00:23:24,520 --> 00:23:27,160 One that can see beyond the visible. 352 00:23:45,800 --> 00:23:48,760 Fundamentally the telescope is a time machine. 353 00:23:50,560 --> 00:23:52,640 A telescope is always a time machine, 354 00:23:52,720 --> 00:23:54,880 because your eye is a time machine. 355 00:23:54,960 --> 00:23:58,240 You can see things as they were, when they send light to you. 356 00:23:59,600 --> 00:24:02,320 And it takes two-and-a-half seconds for light 357 00:24:02,400 --> 00:24:04,400 to go from here to the moon and back. 358 00:24:06,200 --> 00:24:11,480 You see the sun as it was 500 seconds ago. About eight minutes. 359 00:24:13,240 --> 00:24:16,400 We're six feet apart, so you are seeing me six nanoseconds... 360 00:24:17,880 --> 00:24:21,280 As I was, six nanoseconds before you see me. 361 00:24:21,360 --> 00:24:23,960 So, light travels at the speed of one foot per nanosecond 362 00:24:24,040 --> 00:24:27,040 in round numbers. You're seeing the Andromeda nebula 363 00:24:27,120 --> 00:24:29,520 as it was about three million years ago. 364 00:24:29,600 --> 00:24:32,640 And that's about as far as you can see without a telescope. 365 00:24:32,720 --> 00:24:35,840 But with a telescope, you can see billions and billions 366 00:24:35,920 --> 00:24:38,160 of light-years out in space. 367 00:24:38,240 --> 00:24:41,040 So, billions and billions of years back in time. 368 00:24:46,320 --> 00:24:48,640 Of course, by now, they are much farther away 369 00:24:48,720 --> 00:24:50,360 than they were when we saw them. 370 00:24:51,680 --> 00:24:54,080 So, those things are not there any more. 371 00:24:54,160 --> 00:24:56,080 They have gone on to do something else. 372 00:24:57,520 --> 00:24:59,600 Some parts of the universe we'll never see, 373 00:24:59,680 --> 00:25:01,920 because they are accelerating away from us now. 374 00:25:02,960 --> 00:25:05,000 So, they are going to accelerate away so far 375 00:25:05,080 --> 00:25:08,440 that the light from them will never get here. 376 00:25:21,840 --> 00:25:23,800 As we look deeper and deeper and deeper, 377 00:25:23,880 --> 00:25:26,120 we see fewer and fewer galaxies. 378 00:25:31,560 --> 00:25:33,560 It's not that we're running out of galaxies. 379 00:25:35,080 --> 00:25:37,520 It was the fact that as the universe is expanding, 380 00:25:37,600 --> 00:25:39,640 it's stretching across space and time, 381 00:25:39,720 --> 00:25:41,920 its light is being redshifted, and galaxies 382 00:25:42,000 --> 00:25:44,240 from the very early universe are being shifted 383 00:25:44,320 --> 00:25:46,560 out of view of the Hubble Space Telescope. 384 00:25:46,640 --> 00:25:49,520 The Hubble Telescope can only see what you can see with your eye. 385 00:25:49,600 --> 00:25:51,720 The wavelengths that your eye is sensitive to, 386 00:25:51,800 --> 00:25:55,080 plus a little bit of ultraviolet, and a little bit of infrared. 387 00:25:55,160 --> 00:25:57,240 Those galaxies are so far away from us, 388 00:25:57,320 --> 00:26:00,680 that as light travels through space, and space is expanding, 389 00:26:00,760 --> 00:26:03,840 the universe is expanding, the light gets redshifted. 390 00:26:04,360 --> 00:26:07,560 So, it changes from blue light into red light, 391 00:26:07,640 --> 00:26:10,000 as it travels through space. 392 00:26:10,080 --> 00:26:12,960 It's so far away from us, and so far back in time, 393 00:26:13,040 --> 00:26:15,880 its light only reaches us via infrared wavelengths. 394 00:26:16,920 --> 00:26:19,400 The Webb is going to give us infrared eyes. 395 00:26:19,480 --> 00:26:22,720 And we'll see a part of the universe we've never seen before. 396 00:26:26,160 --> 00:26:28,400 The Hubble Space Telescope has transformed 397 00:26:28,480 --> 00:26:31,280 our knowledge of the universe. 398 00:26:32,160 --> 00:26:34,640 But we haven't been able to study the first galaxies 399 00:26:34,720 --> 00:26:36,920 that formed in the universe. 400 00:26:37,000 --> 00:26:39,640 We haven't been able to find their light. 401 00:26:39,720 --> 00:26:42,920 And that's what the James Webb Space Telescope would provide. 402 00:26:52,280 --> 00:26:54,160 My team is contamination control. 403 00:26:54,240 --> 00:26:58,080 But there's mechanical, propulsion, the sun shield. 404 00:26:58,160 --> 00:27:01,520 There's the spacecraft. Is this membrane shaped right? 405 00:27:01,600 --> 00:27:04,120 Is the UPS clamshell, that's going around the sun shield 406 00:27:04,200 --> 00:27:06,440 when it's stowed up, is that the right material? 407 00:27:06,520 --> 00:27:09,200 Is it going to hold it in place? To keep the membranes 408 00:27:09,280 --> 00:27:11,080 from wrinkling when you launch. 409 00:27:11,160 --> 00:27:14,160 Are instrument models correct? Are particle models correct? 410 00:27:14,240 --> 00:27:16,640 Cos, of course, I'm thinking about keeping it clean. 411 00:27:16,720 --> 00:27:19,480 This is the first time we've flown mirrors this light. 412 00:27:19,560 --> 00:27:22,200 It's the first time we are building a deployed telescope. 413 00:27:22,280 --> 00:27:26,120 What are our profiles for temperature, for cooldown? Our cryo-strength. Oh, my gosh. 414 00:27:26,200 --> 00:27:29,280 We have actuators on here more precise than we've ever used before. 415 00:27:29,360 --> 00:27:31,680 Because we have to align the individual mirrors. 416 00:27:31,760 --> 00:27:35,960 Is it going to hold, keep its strength? Is it going to keep its alignment? Will it deploy? 417 00:27:36,040 --> 00:27:39,560 The sun shield alone has 137 release devices. 418 00:27:39,640 --> 00:27:43,360 I think the count on the entire spacecraft is 189. 419 00:27:43,440 --> 00:27:47,560 Something like that. That is a lot of single-point failures. 420 00:27:47,640 --> 00:27:51,440 They've looked at every step. But it's so big, you don't know what steps you missed. 421 00:27:51,520 --> 00:27:53,960 And that's the big problem. The unknown unknowns. 422 00:27:54,040 --> 00:27:56,600 Everybody's afraid of the unknown unknowns. 423 00:27:57,840 --> 00:27:59,880 There's nothing I can say that can come close 424 00:27:59,960 --> 00:28:04,480 to describing how technically difficult this telescope is. 425 00:28:05,120 --> 00:28:09,160 The one thing that scares the hell out of me is failure of imagination. 426 00:28:09,720 --> 00:28:14,000 Failure to imagine something that we could have fixed on the ground. 427 00:28:14,080 --> 00:28:16,360 That's my recurring nightmare. 428 00:28:19,400 --> 00:28:22,920 We don't want the telescope portion of the Webb Telescope 429 00:28:23,000 --> 00:28:25,680 to see any of the sun. 430 00:28:25,760 --> 00:28:28,880 The light that we're looking at are in the infrared. 431 00:28:29,720 --> 00:28:33,160 So, in order to detect heat signature, infrared signature, 432 00:28:33,240 --> 00:28:35,240 it obviously needs to be very cold, 433 00:28:35,320 --> 00:28:38,320 or all it's going to measure is itself, basically. 434 00:28:38,600 --> 00:28:40,800 So, we need to keep it very cold. And in space, 435 00:28:40,880 --> 00:28:43,080 really the only thing that will heat you up 436 00:28:43,160 --> 00:28:45,920 is the electronics that you've got, and the really bright source, 437 00:28:46,000 --> 00:28:49,280 which is the sun. We don't want to blind ourselves. 438 00:28:50,360 --> 00:28:54,920 And this makes us put the satellite far enough away from the Earth 439 00:28:55,000 --> 00:28:59,280 so that it is not influenced by the heat coming from the Earth. 440 00:28:59,360 --> 00:29:02,200 We're not going in and out of the sun. 441 00:29:02,280 --> 00:29:07,040 And so, this drives us to orbit the so-called Earth-sun L2 point. 442 00:29:09,320 --> 00:29:12,280 One million miles away from the Earth and away from the sun. 443 00:29:13,680 --> 00:29:16,160 So, we can't afford a mistake. 444 00:29:17,360 --> 00:29:21,000 Because out at L2, repair man doesn't make a house call. 445 00:29:21,080 --> 00:29:22,760 We don't get that second chance. 446 00:29:22,840 --> 00:29:26,000 It's a one strike and you are out of business. 447 00:29:26,120 --> 00:29:29,280 Have to hit the pitch out of the park. 448 00:29:29,360 --> 00:29:32,760 All the way out of the park. A million miles out of the park. 449 00:29:32,840 --> 00:29:35,280 This is an engineering marvel. 450 00:29:35,360 --> 00:29:38,240 It's not actually, necessarily just a scientific marvel. 451 00:29:38,320 --> 00:29:40,600 Because we've built big telescopes before. 452 00:29:42,000 --> 00:29:44,720 I built an eight metre telescope on the ground. 453 00:29:47,240 --> 00:29:51,000 We used 300 tonnes of steel to build this telescope. 454 00:29:53,080 --> 00:29:56,760 But there's no way to launch a telescope of that scale into space. 455 00:29:56,840 --> 00:30:01,000 The James Webb weighs six metric tonnes. 456 00:30:01,080 --> 00:30:05,520 We have to go from 300 tonnes, down to six tonnes. 457 00:30:05,600 --> 00:30:08,320 There's no rocket big enough to launch anything this big. 458 00:30:08,400 --> 00:30:11,360 So we then have to work out how to fold this telescope up. 459 00:30:11,440 --> 00:30:13,840 We had to create this origami telescope. 460 00:30:18,640 --> 00:30:22,240 There are over, you know, 300, to 400 different operations 461 00:30:22,320 --> 00:30:25,760 that have to occur to make this telescope actually come to life. 462 00:30:30,440 --> 00:30:34,080 A huge sunshade has to deploy, which is the size of a tennis court. 463 00:30:35,240 --> 00:30:37,240 At this point, things get pretty critical, 464 00:30:37,320 --> 00:30:39,440 because everything starts to cool quickly. 465 00:30:39,520 --> 00:30:41,480 Now we have to get the telescope unfolded 466 00:30:41,560 --> 00:30:43,960 before it gets too cold, and the joints freeze up. 467 00:30:44,040 --> 00:30:46,320 Then we've got to get the mirrors unfolded. 468 00:30:46,400 --> 00:30:48,640 We've then got to get the instruments started. 469 00:30:48,720 --> 00:30:52,400 And each one of these things has to work perfectly first time. 470 00:30:54,080 --> 00:30:56,560 We get one shot to get this telescope right. 471 00:30:57,920 --> 00:31:01,680 The slightest thing goes wrong, and this mission could fail. 472 00:31:07,600 --> 00:31:11,040 From its vantage point, at L2, Webb will do more 473 00:31:11,120 --> 00:31:13,360 than see the first galaxies. 474 00:31:13,440 --> 00:31:16,240 It will also be able to peer through the dust clouds, 475 00:31:16,320 --> 00:31:19,800 to where stars are being born, and it will investigate 476 00:31:19,880 --> 00:31:22,640 small objects of particular importance for us. 477 00:31:23,880 --> 00:31:26,360 Exoplanets. 478 00:31:40,160 --> 00:31:42,880 There are five naked-eye planets: 479 00:31:42,960 --> 00:31:46,000 Mercury, Venus, Mars, Jupiter, Saturn. 480 00:31:47,360 --> 00:31:52,360 With telescopes, three more were discovered. Uranus, Neptune, Pluto. 481 00:31:52,440 --> 00:31:54,480 Then Pluto got demoted. 482 00:31:54,560 --> 00:31:59,080 So, counting the Earth, we know of eight planets in the entire universe. 483 00:32:02,600 --> 00:32:06,120 The idea of an exoplanet, a planet outside the solar system 484 00:32:06,200 --> 00:32:09,120 was the realm of science fiction. 485 00:32:09,200 --> 00:32:12,200 But then, all that changed. 486 00:32:12,280 --> 00:32:15,560 I started out working on exoplanets in graduate school. 487 00:32:16,200 --> 00:32:19,160 At the time, there was one single transiting planet known - 488 00:32:19,240 --> 00:32:22,000 HD 209458(b). 489 00:32:22,840 --> 00:32:25,680 But I knew the field would explode. 490 00:32:25,760 --> 00:32:28,840 I said, 'Look, I know there's going to be so many planets transiting, 491 00:32:28,920 --> 00:32:31,040 we're not going to be able to count them all.' 492 00:32:31,120 --> 00:32:35,040 The first exoplanets were discovered from the ground. 493 00:32:35,720 --> 00:32:38,000 We saw... 494 00:32:38,720 --> 00:32:41,040 ..just stars wobbling. 495 00:32:41,120 --> 00:32:43,800 And we convinced ourselves that the wobbling of stars 496 00:32:43,880 --> 00:32:45,880 was due to planets around them. 497 00:32:50,400 --> 00:32:52,840 The early planets found were the Jupiters. 498 00:32:53,280 --> 00:32:57,200 Which really made their star wobble. That's how we could detect them. 499 00:32:57,280 --> 00:33:00,080 Then the Kepler Space Telescope went up. 500 00:33:07,240 --> 00:33:10,400 Nowadays, the best way to find planets is by the transit technique. 501 00:33:12,280 --> 00:33:14,600 If you're lucky, the planet will orbit, 502 00:33:14,680 --> 00:33:16,920 such that it passes in front of the stars. 503 00:33:18,360 --> 00:33:21,600 Then the starlight drops by a tiny amount. 504 00:33:21,680 --> 00:33:23,320 If it's a Jupiter-sized planet, 505 00:33:23,400 --> 00:33:25,360 Jupiter is a 10th the size of our sun, 506 00:33:25,440 --> 00:33:29,800 it will block out one 100th of the brightness of the star. 507 00:33:31,920 --> 00:33:37,400 Now, if it's an Earth in the sun, it's one 10,000th. 508 00:33:37,480 --> 00:33:39,920 Tiny. But measurable. 509 00:33:44,120 --> 00:33:47,960 The Kepler Space Telescope monitored one small section of the sky. 510 00:33:49,240 --> 00:33:51,360 And it found thousands of planets. 511 00:33:54,160 --> 00:33:57,080 While space telescopes have the sharpness 512 00:33:57,160 --> 00:33:59,080 needed to find an exoplanet, 513 00:33:59,160 --> 00:34:02,320 ground telescopes can still be made much larger. 514 00:34:02,400 --> 00:34:04,200 And with new adaptive optics, 515 00:34:04,280 --> 00:34:07,440 to compensate for the Earth's atmosphere, 516 00:34:07,520 --> 00:34:12,160 they can gather enough light to study the exoplanet in more detail. 517 00:34:13,520 --> 00:34:17,520 I think one of the, for me, the most magnificent moments, 518 00:34:17,600 --> 00:34:22,840 was very recently, when we managed to image an exoplanet. 519 00:34:22,920 --> 00:34:26,520 We managed to block the light of the star, and there it appears. 520 00:34:26,600 --> 00:34:29,200 We see it moving, actually. It's fantastic. 521 00:34:29,560 --> 00:34:32,120 We see here, as humans, for the first time, 522 00:34:32,200 --> 00:34:34,680 another planet moving around its star. 523 00:34:34,760 --> 00:34:37,440 It looks so harmless. A few pixels. 524 00:34:37,520 --> 00:34:39,640 You realise what it means for humankind 525 00:34:39,720 --> 00:34:42,800 to actually see another planet moving around the sun. 526 00:34:42,880 --> 00:34:45,160 It's incredible, I think. 527 00:34:47,960 --> 00:34:51,680 The segmented mirror of the Keck Telescope was the model for Webb. 528 00:34:52,560 --> 00:34:55,200 And points the way to larger telescopes, 529 00:34:55,280 --> 00:34:58,320 on the ground, and in space, that will be needed 530 00:34:58,400 --> 00:35:02,320 to probe the atmospheres of exoplanets for signs of life. 531 00:35:03,800 --> 00:35:05,920 We'd like to find water vapour. 532 00:35:06,000 --> 00:35:08,040 Because water vapour in a small planet 533 00:35:08,120 --> 00:35:10,120 indicates a liquid water ocean. 534 00:35:10,200 --> 00:35:12,280 All life on Earth needs liquid water. 535 00:35:12,360 --> 00:35:15,560 It's a great place to start to identify habitable worlds. 536 00:35:15,640 --> 00:35:19,680 We'd like to see carbon dioxide, indicates it's truly a rocky world. 537 00:35:19,760 --> 00:35:21,840 But beyond water vapour and carbon dioxide, 538 00:35:21,920 --> 00:35:25,040 what we'd really like to find are gases that don't belong. 539 00:35:26,040 --> 00:35:28,520 Here on our own Earth we have oxygen. 540 00:35:28,600 --> 00:35:31,560 But without plants, and other photosynthetic life, 541 00:35:31,640 --> 00:35:34,440 we would have virtually no oxygen in our atmosphere. 542 00:35:36,080 --> 00:35:39,200 If we found a planet with life, honestly, any life, 543 00:35:39,280 --> 00:35:41,280 it would be very exciting. 544 00:35:41,360 --> 00:35:44,960 But the most exciting thing is intelligent life. 545 00:35:45,760 --> 00:35:49,200 Personal guess is that there's life in many places elsewhere universe. 546 00:35:49,280 --> 00:35:52,200 And I have one bit of observational evidence. 547 00:35:52,280 --> 00:35:54,760 Which is that here on Earth, as soon as 548 00:35:54,840 --> 00:35:58,440 the bombardment of comets and asteroids came to an end, 549 00:35:58,520 --> 00:36:01,360 we have evidence of fossil life here. 550 00:36:01,440 --> 00:36:03,760 That's evidence that it happened quickly. 551 00:36:03,840 --> 00:36:06,320 So if it happened quickly, maybe it happens easily. 552 00:36:06,400 --> 00:36:11,160 Can we find them? I think we will. In my lifetime? God, I hope so. 553 00:36:12,360 --> 00:36:16,000 Because that's... I want to know. You know? 554 00:36:19,440 --> 00:36:22,680 I am pretty much convinced there is life beyond the solar system. 555 00:36:22,760 --> 00:36:25,040 There are so many places where it could occur. 556 00:36:28,440 --> 00:36:32,320 If you look at the ten most common chemical elements in our bodies, 557 00:36:32,440 --> 00:36:36,480 they are the ten most common chemical elements in the universe. 558 00:36:37,080 --> 00:36:39,920 The ingredients which make life on Earth are ingredients 559 00:36:40,000 --> 00:36:43,520 which are the most common in the universe. 560 00:36:43,600 --> 00:36:46,400 We have the ingredients, we just need the one spark 561 00:36:46,480 --> 00:36:48,520 to ignite life at some point. 562 00:36:51,080 --> 00:36:54,520 There are just so many types of planets just waiting to be found. 563 00:36:55,880 --> 00:36:58,480 The James Webb Space Telescope is our first shot 564 00:36:58,560 --> 00:37:01,080 at studying atmospheres of small planets. 565 00:37:02,080 --> 00:37:04,160 If we are really lucky, that would be literally 566 00:37:04,240 --> 00:37:06,840 like winning the lottery five times in a row. 567 00:37:06,920 --> 00:37:09,200 If there are planets around every small star. 568 00:37:09,280 --> 00:37:11,760 And there are many, many of those in the habitable zone, 569 00:37:11,840 --> 00:37:14,280 and all of those have life on them. And if that life, 570 00:37:14,360 --> 00:37:16,560 half of it, let's say, produces gases, 571 00:37:16,640 --> 00:37:19,160 we actually have a shot of detecting that. 572 00:37:21,040 --> 00:37:23,440 We have the shot at finding life for the first time 573 00:37:23,520 --> 00:37:26,240 in human history, with the James Webb Space Telescope. 574 00:37:33,280 --> 00:37:37,400 Layer five. On three, two, one. 575 00:37:49,800 --> 00:37:53,440 We're entering a new era. We're actually building telescopes, 576 00:37:53,520 --> 00:37:58,520 not just to satisfy our curiosity, but ultimately for our survival. 577 00:38:00,000 --> 00:38:03,160 We are building a telescope in Chile to scan the sky 578 00:38:03,240 --> 00:38:06,640 with a massive camera, that will actually be able 579 00:38:06,720 --> 00:38:09,240 to characterise asteroids. The kind of things 580 00:38:09,320 --> 00:38:13,000 that wiped out the dinosaurs. We want to catalogue all of those, 581 00:38:13,080 --> 00:38:16,360 so we get a heads-up if one's coming our way. 582 00:38:24,520 --> 00:38:28,440 We're building a telescope on Haleakala, in Maui. 583 00:38:28,600 --> 00:38:32,240 A four-metre reflecting telescope, just to look at the sun. 584 00:38:40,640 --> 00:38:45,040 Our sun is at about the same stage in its life 585 00:38:45,120 --> 00:38:47,160 as I am in my life. OK. 586 00:38:47,240 --> 00:38:49,440 It's about a third, a little bit more than a third 587 00:38:49,520 --> 00:38:51,480 of the way through its life. 588 00:38:51,560 --> 00:38:55,600 But when I'm 10% older, I'm going to be 40. 589 00:38:55,680 --> 00:38:57,800 I'm going to be about the same, hopefully. 590 00:38:57,880 --> 00:39:00,000 But our sun, when our sun is 10% older, 591 00:39:00,080 --> 00:39:02,360 it's going to be 10% brighter. 592 00:39:02,440 --> 00:39:05,120 Our atmosphere's going to start drying out. 593 00:39:05,200 --> 00:39:09,160 When the sun is 30% older, it's going to be 40% brighter. 594 00:39:09,240 --> 00:39:12,320 That's enough to dry out the oceans on our planet. 595 00:39:12,400 --> 00:39:15,320 Eventually, the sun is going to expand, and balloon. 596 00:39:15,400 --> 00:39:19,000 It's going to run out of hydrogen, its outer layers are going to expand 597 00:39:19,080 --> 00:39:23,680 to a distance that encompasses the orbit of the Earth around the sun. 598 00:39:24,720 --> 00:39:28,000 So, it's going to obliterate the inner solar system. 599 00:39:28,080 --> 00:39:31,040 So, it's inevitable that we have to leave our home. 600 00:39:31,880 --> 00:39:34,320 But where do we go? 601 00:39:43,880 --> 00:39:46,160 We now know there are at least 100 billion 602 00:39:46,240 --> 00:39:48,480 other planetary systems in our galaxy. 603 00:39:49,880 --> 00:39:52,000 So, an obvious question becomes, 604 00:39:52,080 --> 00:39:54,280 is there another home for the human race? 605 00:40:03,360 --> 00:40:06,160 Another Earth is undoubtedly out there. 606 00:40:06,240 --> 00:40:09,240 In our own Milky Way galaxy, we've hundreds of billions of stars. 607 00:40:09,320 --> 00:40:11,880 Our own universe has hundreds of billions of galaxies. 608 00:40:14,880 --> 00:40:17,320 To me, personally, it is definitely there. 609 00:40:21,520 --> 00:40:24,080 We believe every star in our Milky Way galaxy 610 00:40:24,160 --> 00:40:26,240 should have at least one planet. 611 00:40:29,240 --> 00:40:32,880 And we're hoping to find and identify a pool of transiting planets 612 00:40:32,960 --> 00:40:35,240 in the habitable zones of small stars. 613 00:40:35,320 --> 00:40:37,240 We call it the Goldilocks Zone. 614 00:40:38,120 --> 00:40:41,000 Not too hot, and not too cold, but just right for life. 615 00:40:43,120 --> 00:40:45,320 We're betting on the fact that nature delivers. 616 00:40:45,400 --> 00:40:48,120 That nature has created many rocky planets. 617 00:40:48,200 --> 00:40:50,400 And we are planning on finding it. 618 00:40:52,520 --> 00:40:56,840 Airspeed is live. 40 knots. 619 00:41:02,680 --> 00:41:06,320 It is amazing that in just a little over 100 years, we have gone from 620 00:41:06,400 --> 00:41:09,200 watching birds fly, to having got to the moon. 621 00:41:10,960 --> 00:41:13,080 We've launched 135 shuttles. 622 00:41:13,920 --> 00:41:16,000 We are doing the preliminary exploration 623 00:41:16,080 --> 00:41:18,320 to find out where are we going. 624 00:41:20,040 --> 00:41:24,760 When you're flying, it seems almost like being over the horizon. 625 00:41:24,840 --> 00:41:27,320 Makes me think about what other worlds 626 00:41:27,400 --> 00:41:30,040 are out there that are like this. 627 00:41:30,120 --> 00:41:32,640 That have water and land. 628 00:41:33,160 --> 00:41:37,040 The James Webb Space Telescope will go where no Hubble has gone before. 629 00:41:37,640 --> 00:41:40,480 But the next step is to go where people have never gone before. 630 00:41:40,560 --> 00:41:43,320 To send women and men off to Mars. 631 00:41:45,000 --> 00:41:48,760 And I do believe that 100 years from now, or 1,000 years from now, 632 00:41:48,840 --> 00:41:51,760 we're going to be looking to go to some nearby star 633 00:41:51,840 --> 00:41:54,000 that has an Earth 2.0 around it. 634 00:41:56,400 --> 00:41:59,640 These are real worlds that are out there right now. 635 00:41:59,720 --> 00:42:02,800 These are planets, orbiting stars, with moons, 636 00:42:02,880 --> 00:42:06,560 and water, and weather, 637 00:42:06,640 --> 00:42:10,480 and clouds, and sunsets, and moonrises. 638 00:42:11,960 --> 00:42:16,320 All of the things that we see on Earth that we love 639 00:42:16,400 --> 00:42:18,680 almost certainly exist elsewhere in the universe. 640 00:42:21,120 --> 00:42:25,320 If we had a starship today that would take decades, 641 00:42:25,400 --> 00:42:28,160 or even centuries to get to Earth 2.0, 642 00:42:28,240 --> 00:42:31,200 I'd volunteer to go up, knowing that 643 00:42:31,320 --> 00:42:33,800 it's great grandkids that will make it. 644 00:42:35,280 --> 00:42:39,800 Because of telescopes, it's a special point in human history. 645 00:42:42,400 --> 00:42:45,960 We can see the whole landscape, the cosmic landscape, laid out. 646 00:42:46,960 --> 00:42:48,640 From the very beginning in time, 647 00:42:48,720 --> 00:42:51,280 from the present, and into our future. 648 00:42:51,360 --> 00:42:53,760 Out into the stars. 649 00:42:59,280 --> 00:43:01,840 Looking at the night sky is different for me now. 650 00:43:02,600 --> 00:43:05,520 Changed by knowing that virtually every star 651 00:43:05,600 --> 00:43:07,760 has at least one planet around it. 652 00:43:09,120 --> 00:43:12,760 It's a shift of perspective as big as Galileo finding evidence 653 00:43:12,840 --> 00:43:15,920 that the Earth wasn't at the centre of the universe. 654 00:43:17,880 --> 00:43:20,440 Maybe knowing that other worlds exist out there 655 00:43:20,520 --> 00:43:24,240 can unify us, inspire us to work together. 656 00:43:26,400 --> 00:43:29,280 We may not be the ones who will venture to the stars. 657 00:43:30,360 --> 00:43:33,400 But with the telescopes we are building, and that we will build, 658 00:43:33,480 --> 00:43:38,400 we can be the ones who begin that great journey. 659 00:43:55,880 --> 00:43:57,800 subtitles by Deluxe