1 00:00:08,320 --> 00:00:11,359 Hello, and welcome to the Physics World weekly 2 00:00:11,359 --> 00:00:11,859 podcast. 3 00:00:12,175 --> 00:00:13,315 I'm Hamish Johnston. 4 00:00:13,695 --> 00:00:16,095 In this episode, we're going to chat about 5 00:00:16,095 --> 00:00:17,795 the science and fiction 6 00:00:18,095 --> 00:00:18,995 of exoplanets, 7 00:00:19,855 --> 00:00:22,815 which are planets that orbit stars other than 8 00:00:22,815 --> 00:00:23,475 the sun. 9 00:00:23,935 --> 00:00:25,875 I'm joined by Keith Cooper, 10 00:00:26,280 --> 00:00:29,660 a journalist and author who's a regular contributor 11 00:00:29,800 --> 00:00:31,019 to Physics World. 12 00:00:31,480 --> 00:00:34,940 Keith studied physics and astronomy at the University 13 00:00:35,000 --> 00:00:35,820 of Manchester, 14 00:00:36,280 --> 00:00:37,979 and he's written extensively 15 00:00:38,679 --> 00:00:39,579 about astronomy, 16 00:00:40,155 --> 00:00:40,655 astrophysics, 17 00:00:41,034 --> 00:00:41,854 and cosmology. 18 00:00:42,635 --> 00:00:45,695 He's also a big fan of science fiction, 19 00:00:46,234 --> 00:00:48,495 and his new book about exoplanets 20 00:00:49,195 --> 00:00:50,015 is called 21 00:00:50,475 --> 00:00:53,375 Amazing Worlds of Science Fiction 22 00:00:53,755 --> 00:00:55,289 and Science Fact. 23 00:00:55,850 --> 00:00:56,590 Hi, Keith. 24 00:00:56,969 --> 00:00:58,270 Welcome to the podcast. 25 00:00:59,130 --> 00:01:00,810 Hi, Hamish. Thank you for having me on 26 00:01:00,810 --> 00:01:01,390 the show. 27 00:01:02,409 --> 00:01:04,329 To begin with, Keith, we should make it 28 00:01:04,329 --> 00:01:05,950 very clear that exoplanets 29 00:01:06,250 --> 00:01:07,549 are real things. 30 00:01:08,134 --> 00:01:09,974 In fact, in the last thirty years or 31 00:01:09,974 --> 00:01:13,094 so, I think astronomers have discovered thousands of 32 00:01:13,094 --> 00:01:15,194 them. So can you give our listeners 33 00:01:15,894 --> 00:01:17,034 a bit of an introduction 34 00:01:17,734 --> 00:01:18,474 to exoplanets 35 00:01:18,854 --> 00:01:20,774 and and the science of of how they're 36 00:01:20,774 --> 00:01:21,274 studied? 37 00:01:21,655 --> 00:01:22,155 Sure. 38 00:01:23,009 --> 00:01:25,829 This year, 2025, is actually the thirtieth anniversary 39 00:01:26,369 --> 00:01:28,149 of the discovery of the first exoplanets 40 00:01:28,450 --> 00:01:31,030 around a sun like star. Now they discovered 41 00:01:31,729 --> 00:01:34,209 freak planets around pulsars a couple of years 42 00:01:34,209 --> 00:01:37,295 before that, but it was, October 1995 when 43 00:01:37,295 --> 00:01:39,775 the first discovery was made. The planet was 44 00:01:39,775 --> 00:01:41,795 called 51 Pegasi b, 45 00:01:42,174 --> 00:01:43,935 and it's what we call a hot Jupiter, 46 00:01:43,935 --> 00:01:45,855 which if you can imagine Jupiter in our 47 00:01:45,855 --> 00:01:47,549 solar system, it's a big gas bag. 48 00:01:48,350 --> 00:01:49,409 And then you move 49 00:01:49,710 --> 00:01:51,630 it really close to the sun. That's what 50 00:01:51,630 --> 00:01:52,850 this planet was like. 51 00:01:53,310 --> 00:01:55,790 Astronomers had no idea that such planets could 52 00:01:55,790 --> 00:01:57,090 exist. They were expecting 53 00:01:57,469 --> 00:02:00,109 other planetary systems to look like our solar 54 00:02:00,109 --> 00:02:02,750 system with the small rocky worlds closer to 55 00:02:02,750 --> 00:02:05,444 the sun and the big gas giants further 56 00:02:05,444 --> 00:02:07,765 out. So this was a big shock. Took 57 00:02:07,765 --> 00:02:09,925 a little while to understand how this could 58 00:02:09,925 --> 00:02:12,564 be. We we finally realized that the big 59 00:02:12,564 --> 00:02:15,604 hot Jupiters actually did form further out from 60 00:02:15,604 --> 00:02:17,925 the star, but then through interactions with the 61 00:02:17,925 --> 00:02:18,425 protoplanetary 62 00:02:18,724 --> 00:02:22,199 disk migrated inwards. And we actually realized that 63 00:02:22,199 --> 00:02:24,520 a similar migration had happened in our own 64 00:02:24,520 --> 00:02:27,240 solar system. Jupiter and Saturn had migrated in 65 00:02:27,240 --> 00:02:28,139 a little bit, 66 00:02:28,520 --> 00:02:31,099 and influenced how the inner planets formed. 67 00:02:31,884 --> 00:02:33,724 Fortunately, Jupiter didn't go all the way to 68 00:02:33,724 --> 00:02:35,324 the sun. Otherwise, we wouldn't be here today 69 00:02:35,324 --> 00:02:37,004 to have this conversation because Earth would have 70 00:02:37,004 --> 00:02:39,745 been ejected from the solar system long ago. 71 00:02:39,965 --> 00:02:41,965 And since then, since 1995, 72 00:02:41,965 --> 00:02:44,465 we've discovered almost 6,000 exoplanets. 73 00:02:46,090 --> 00:02:47,769 As I mentioned, some are as big as 74 00:02:47,769 --> 00:02:49,789 Jupiter, others are smaller than Earth. 75 00:02:50,250 --> 00:02:52,090 We found that the most common types of 76 00:02:52,090 --> 00:02:54,250 planets that we found so far are what 77 00:02:54,250 --> 00:02:56,650 we call super Earths. These are we believe 78 00:02:56,650 --> 00:02:58,810 they are rocky worlds that up to 10 79 00:02:58,810 --> 00:03:00,604 times the mass of our planet. 80 00:03:01,705 --> 00:03:04,585 We have found planets in what we describe 81 00:03:04,585 --> 00:03:07,805 as the habitable zone, which is a region 82 00:03:08,025 --> 00:03:10,185 from a star where temperatures are just about 83 00:03:10,185 --> 00:03:13,004 right for liquid water, assuming that this planet 84 00:03:13,064 --> 00:03:14,685 has an atmosphere like Earth's. 85 00:03:15,349 --> 00:03:16,709 But we don't know whether any of these 86 00:03:16,709 --> 00:03:19,189 worlds are actually habitable. We don't know much 87 00:03:19,189 --> 00:03:21,269 about them other than their radius and their 88 00:03:21,269 --> 00:03:21,769 mass. 89 00:03:22,389 --> 00:03:23,669 A lot of it is guesswork at this 90 00:03:23,669 --> 00:03:25,689 stage. We have the James Webb Space Telescope 91 00:03:25,750 --> 00:03:26,805 in orbit at the moment, 92 00:03:27,844 --> 00:03:30,664 analyzing these worlds and trying to detect atmospheres 93 00:03:31,044 --> 00:03:33,125 on any of them. It hasn't found any 94 00:03:33,125 --> 00:03:34,584 really yet on these rocky 95 00:03:35,044 --> 00:03:36,424 habitable zone planets. 96 00:03:37,924 --> 00:03:39,924 We've got two more missions launching in in 97 00:03:39,924 --> 00:03:42,084 the coming years from the European Space Agency. 98 00:03:42,084 --> 00:03:42,909 That's PLATO, 99 00:03:43,530 --> 00:03:46,409 which will launch in December 2026 if everything 100 00:03:46,409 --> 00:03:48,650 goes to plan. And then Ariel, which will 101 00:03:48,650 --> 00:03:50,969 characterize the atmospheres of the hot Jupiters that 102 00:03:50,969 --> 00:03:52,669 will launch in 2030. 103 00:03:52,810 --> 00:03:54,669 Of course, we'll still have Webb and Hubble. 104 00:03:55,764 --> 00:03:57,924 We got the extremely large telescope being built 105 00:03:57,924 --> 00:03:59,625 in Chile that's going to be able 106 00:04:00,004 --> 00:04:03,305 to possibly image, directly image some of these, 107 00:04:03,844 --> 00:04:06,245 rocky worlds close to their sun. We we 108 00:04:06,245 --> 00:04:08,965 have directly imaged some planets so far. These 109 00:04:08,965 --> 00:04:10,104 tend to be big, 110 00:04:10,430 --> 00:04:12,669 hot, young planets that are far from their 111 00:04:12,669 --> 00:04:14,750 stand. We we they're still glowing from the 112 00:04:14,750 --> 00:04:16,829 heat of their birth. None of them are 113 00:04:16,829 --> 00:04:18,750 are like Earth. And that's the that's the 114 00:04:18,750 --> 00:04:20,430 thing really. With all these planets, we haven't 115 00:04:20,430 --> 00:04:22,985 found any that are like Earth yet. And 116 00:04:23,044 --> 00:04:25,204 and that's really the quest that most astronomers 117 00:04:25,204 --> 00:04:27,444 are on to find another Earth out there. 118 00:04:27,444 --> 00:04:29,125 I mean, the fact that we haven't found 119 00:04:29,125 --> 00:04:32,425 another Earth, is that is that related to 120 00:04:32,485 --> 00:04:33,704 the sort of biases 121 00:04:34,245 --> 00:04:34,745 within 122 00:04:35,365 --> 00:04:36,584 the way that astronomers, 123 00:04:37,579 --> 00:04:39,120 actually observe these 124 00:04:39,500 --> 00:04:40,639 these, exoplanets, 125 00:04:40,939 --> 00:04:43,660 that it's easier. Well, it's easiest to see 126 00:04:43,660 --> 00:04:46,319 a huge planet very close to its star. 127 00:04:47,979 --> 00:04:49,579 So those are the first things that we 128 00:04:49,579 --> 00:04:51,285 discovered. And are we sort 129 00:04:51,904 --> 00:04:55,025 of narrowing in or focusing in on Earth? 130 00:04:55,025 --> 00:04:57,665 Is it sort of a technological issue? Maybe 131 00:04:57,665 --> 00:04:59,585 not that they don't exist, but that we 132 00:04:59,585 --> 00:05:02,064 can't quite see them yet. Is that safe 133 00:05:02,064 --> 00:05:02,725 to say? 134 00:05:03,259 --> 00:05:05,979 It's definitely a selection effect. But depending on 135 00:05:05,979 --> 00:05:07,819 who you talk to, it may also be 136 00:05:07,819 --> 00:05:09,360 the Earth like planets are rare. 137 00:05:10,459 --> 00:05:12,079 You're right in saying that 138 00:05:14,060 --> 00:05:14,560 detecting 139 00:05:15,100 --> 00:05:17,899 an Earth like world is really on the 140 00:05:17,899 --> 00:05:20,444 very edge of what we could achieve. 141 00:05:20,985 --> 00:05:24,264 James Webb Space Telescope is the only instrument 142 00:05:24,264 --> 00:05:25,644 that we have at the moment 143 00:05:26,105 --> 00:05:28,205 that could potentially do that, 144 00:05:29,144 --> 00:05:31,644 and only in the case of an exoplanet 145 00:05:31,785 --> 00:05:34,205 that orbits a star fairly close to us. 146 00:05:35,120 --> 00:05:37,139 Maybe in in twenty or thirty years, 147 00:05:38,720 --> 00:05:40,800 scientists in The United States have, 148 00:05:41,199 --> 00:05:41,939 an ambition 149 00:05:42,319 --> 00:05:44,560 to launch a they haven't got a proper 150 00:05:44,560 --> 00:05:45,759 name for it yet, but it would it 151 00:05:45,759 --> 00:05:47,839 would be a big giant space telescope with 152 00:05:47,839 --> 00:05:49,764 at least an eight meter mirror, which is 153 00:05:49,764 --> 00:05:52,004 larger than than Webb's 6.5 154 00:05:52,004 --> 00:05:52,504 meter. 155 00:05:53,125 --> 00:05:55,064 And it would be armed with a coronagraph, 156 00:05:55,365 --> 00:05:57,365 which will be able to block out the 157 00:05:57,365 --> 00:05:59,524 light of a star so that we could 158 00:05:59,524 --> 00:06:02,264 actually see the planets, the Earth like planets, 159 00:06:02,839 --> 00:06:05,079 orbiting that star without the stars glare getting 160 00:06:05,079 --> 00:06:05,899 in the way. 161 00:06:06,600 --> 00:06:08,779 Then we may be able to start to 162 00:06:08,839 --> 00:06:11,319 answer whether any of these planets that we're 163 00:06:11,319 --> 00:06:13,819 finding in the habitable zone are really habitable. 164 00:06:14,120 --> 00:06:15,560 But there are there are a lot of 165 00:06:15,560 --> 00:06:17,019 scientists out there who 166 00:06:17,974 --> 00:06:18,875 think that 167 00:06:19,574 --> 00:06:20,954 Earth is really a fluke. 168 00:06:21,414 --> 00:06:23,495 The fact that it is habitable, so many 169 00:06:23,495 --> 00:06:24,875 things had to go right. 170 00:06:26,854 --> 00:06:29,014 Not everybody agrees with that. Some people think 171 00:06:29,014 --> 00:06:31,814 that the scope for life is is broader 172 00:06:31,814 --> 00:06:33,600 than just what we have to offer here 173 00:06:33,600 --> 00:06:35,439 on Earth. Look at look at even in 174 00:06:35,439 --> 00:06:37,600 our own solar system, you know, the detection 175 00:06:37,600 --> 00:06:40,579 of phosphine in Venus' atmosphere still debated. Yes. 176 00:06:40,800 --> 00:06:42,879 But people have talked about microbial life in 177 00:06:42,879 --> 00:06:43,939 Venus' clouds. 178 00:06:44,479 --> 00:06:46,014 Or you go further out. I mean, you 179 00:06:46,014 --> 00:06:48,095 have the moon icy moons of Jupiter and 180 00:06:48,095 --> 00:06:51,394 Saturn that harbor oceans and could have life. 181 00:06:51,535 --> 00:06:53,235 They're very not like Earth. 182 00:06:54,175 --> 00:06:54,675 So 183 00:06:56,654 --> 00:06:59,394 we don't know yet whether Earth like planets 184 00:06:59,479 --> 00:07:02,120 are common. Earth sized planets are probably very 185 00:07:02,120 --> 00:07:04,839 common, but Earth like is a big question 186 00:07:04,839 --> 00:07:07,479 mark. But we have to we we we 187 00:07:07,479 --> 00:07:08,379 shouldn't be, 188 00:07:11,319 --> 00:07:11,954 I guess, 189 00:07:12,914 --> 00:07:16,115 Earth chauvinists, we we we should consider other 190 00:07:16,115 --> 00:07:18,834 habitats that unlike Earth that could still support 191 00:07:18,834 --> 00:07:19,334 life. 192 00:07:20,354 --> 00:07:22,435 And science fiction, you know, can be very 193 00:07:22,435 --> 00:07:24,354 good at doing that. That's right. Yeah. So 194 00:07:24,354 --> 00:07:26,514 so that brings me neatly to my next 195 00:07:26,514 --> 00:07:29,339 question. I mean, we've known about exoplanets for 196 00:07:29,339 --> 00:07:30,479 thirty years, but 197 00:07:30,779 --> 00:07:32,699 I think if you look in fiction, there 198 00:07:32,699 --> 00:07:35,279 is a much longer tradition of 199 00:07:35,660 --> 00:07:36,639 people speculating 200 00:07:36,939 --> 00:07:39,259 about other worlds. I mean, I'm I mean, 201 00:07:39,259 --> 00:07:40,620 I have to say, I I I don't 202 00:07:40,620 --> 00:07:42,334 know much about the history Well 203 00:07:55,194 --> 00:07:55,694 well, 204 00:07:56,074 --> 00:07:56,654 first of 205 00:07:57,860 --> 00:07:59,620 Well well, first of all, you're absolutely right 206 00:07:59,620 --> 00:08:02,180 that that science fiction has portrayed exoplanets long 207 00:08:02,180 --> 00:08:04,759 before we actually knew exoplanets existed. 208 00:08:05,220 --> 00:08:05,720 And 209 00:08:06,579 --> 00:08:07,939 I guess by the time we got to 210 00:08:07,939 --> 00:08:09,939 the nineteen eighties and the nineteen nineties, we 211 00:08:09,939 --> 00:08:11,079 were finding hints. 212 00:08:11,404 --> 00:08:12,225 For example, 213 00:08:13,165 --> 00:08:13,665 the 214 00:08:14,605 --> 00:08:17,485 the infrared astronomy satellite, which was a joint 215 00:08:17,485 --> 00:08:20,605 US, Dutch, UK mission in the eighties, imaged 216 00:08:20,605 --> 00:08:21,105 protoplanetary 217 00:08:21,485 --> 00:08:23,585 disks around beta pic Beta 218 00:08:24,685 --> 00:08:25,824 Pictoris, I think, 219 00:08:26,259 --> 00:08:27,159 and and Vega. 220 00:08:27,939 --> 00:08:29,300 So we had the hints, but we hadn't 221 00:08:29,300 --> 00:08:31,379 found any exoplanets. But going back to the 222 00:08:31,379 --> 00:08:32,919 turn of the twentieth century, 223 00:08:34,100 --> 00:08:36,360 there were two theories about how 224 00:08:37,139 --> 00:08:38,279 planets form. 225 00:08:38,740 --> 00:08:41,074 So one theory was turned out to be 226 00:08:41,074 --> 00:08:42,834 correct that they form from a disk of 227 00:08:42,834 --> 00:08:45,315 matter around a young star coalescing from that 228 00:08:45,315 --> 00:08:47,174 that disk of gas and dust. 229 00:08:47,554 --> 00:08:49,815 The other theory was that a passing star 230 00:08:50,034 --> 00:08:51,554 had come close to the sun and pulled 231 00:08:51,554 --> 00:08:54,194 out some material, and this material had formed 232 00:08:54,194 --> 00:08:54,855 the planets. 233 00:08:55,289 --> 00:08:57,690 And in that model, the planets furthest from 234 00:08:57,690 --> 00:08:59,850 the sun would have formed first. Now I 235 00:08:59,850 --> 00:09:02,089 mentioned this because HG Wells' War of the 236 00:09:02,089 --> 00:09:02,589 Worlds 237 00:09:02,970 --> 00:09:04,490 was written at a time when this was 238 00:09:04,490 --> 00:09:05,709 the prevailing theory. 239 00:09:06,409 --> 00:09:08,649 And it was mentioned in War of the 240 00:09:08,649 --> 00:09:10,595 Worlds that that that was the reason the 241 00:09:10,595 --> 00:09:13,554 the Martians were more technologically advanced than us 242 00:09:13,554 --> 00:09:16,595 on Earth because Mars was older than Earth, 243 00:09:16,595 --> 00:09:19,095 and the Martian species was older than Earth. 244 00:09:21,714 --> 00:09:22,375 I think 245 00:09:23,929 --> 00:09:26,089 that started to change a little. The main 246 00:09:26,089 --> 00:09:28,110 problem at this at the time was, 247 00:09:28,730 --> 00:09:30,569 the problem of angular momentum in in the 248 00:09:30,569 --> 00:09:31,069 protoplanetary 249 00:09:31,370 --> 00:09:33,789 disk and and the sun, and how how 250 00:09:34,089 --> 00:09:36,654 we lost that that angular momentum. It's still 251 00:09:36,654 --> 00:09:37,955 a little bit of a problem, 252 00:09:38,735 --> 00:09:40,495 but we we do know that planets form 253 00:09:40,495 --> 00:09:41,934 from the disc now. We've seen it that 254 00:09:41,934 --> 00:09:42,595 in action. 255 00:09:43,455 --> 00:09:44,595 One of the early, 256 00:09:45,134 --> 00:09:47,695 twentieth century science fiction writers was e Doc 257 00:09:47,695 --> 00:09:48,195 Smith. 258 00:09:48,929 --> 00:09:51,009 He wrote the Lensman series, and before that, 259 00:09:51,009 --> 00:09:53,809 he wrote the Skylark of Space. Now Doc 260 00:09:53,809 --> 00:09:56,549 Smith is famous as a science fiction writer, 261 00:09:56,690 --> 00:09:57,190 but 262 00:09:57,570 --> 00:10:00,529 anyone who eats donuts knows him intimately because 263 00:10:00,529 --> 00:10:02,210 he was the guy who figured out how 264 00:10:02,210 --> 00:10:04,964 to get sugar to stick to donuts. Oh, 265 00:10:05,264 --> 00:10:07,205 wow. I thought sugar stuck to everything. 266 00:10:08,985 --> 00:10:09,485 Yeah. 267 00:10:11,664 --> 00:10:13,664 And and and in in his books, you 268 00:10:13,664 --> 00:10:16,004 know, he had space faring civilizations 269 00:10:16,384 --> 00:10:18,899 visiting other planets around other stars. And in 270 00:10:18,899 --> 00:10:20,200 the twenties and thirties, 271 00:10:21,860 --> 00:10:24,600 more authors, more science fiction writers began to 272 00:10:26,419 --> 00:10:28,899 to have stories along the same lines. Isaac 273 00:10:28,899 --> 00:10:29,399 Asimov, 274 00:10:30,339 --> 00:10:32,820 started writing Foundation in the early nineteen forties. 275 00:10:32,820 --> 00:10:34,745 That was about a galactic empire. 276 00:10:38,164 --> 00:10:40,884 And Star Trek, obviously, got visiting strange new 277 00:10:40,884 --> 00:10:41,384 worlds. 278 00:10:41,764 --> 00:10:44,105 And, you know, if you watch Star Trek 279 00:10:44,164 --> 00:10:46,004 in the nineteen sixties, you could probably be 280 00:10:46,004 --> 00:10:48,565 forgiven for thinking that astronomers already knew all 281 00:10:48,565 --> 00:10:51,009 these worlds were out there. But we didn't 282 00:10:51,009 --> 00:10:53,090 know at the time. It was it was 283 00:10:53,090 --> 00:10:55,169 just guesswork. We needed somewhere for our heroes 284 00:10:55,169 --> 00:10:57,090 to visit. So we had to imagine these 285 00:10:57,090 --> 00:10:57,590 planets. 286 00:10:58,610 --> 00:11:01,350 All those Star Trek planets that look suspiciously 287 00:11:01,649 --> 00:11:03,164 like the back back lot 288 00:11:03,644 --> 00:11:05,664 in Los Angeles. Yes. Yes. 289 00:11:06,044 --> 00:11:08,044 Lots lots of cowboy planets and there was 290 00:11:08,044 --> 00:11:10,704 a, 19 planet, gangster planet. 291 00:11:12,125 --> 00:11:12,625 But 292 00:11:13,004 --> 00:11:14,304 I think science fiction 293 00:11:14,764 --> 00:11:17,565 does have a lot of worlds that are 294 00:11:17,565 --> 00:11:18,690 very much like Earth, 295 00:11:19,090 --> 00:11:20,950 especially in movies and TV. 296 00:11:21,330 --> 00:11:23,409 And that can be forgiven because we can't 297 00:11:23,409 --> 00:11:25,730 send actors to Mars. They, you know, they 298 00:11:25,730 --> 00:11:26,470 have to, 299 00:11:27,409 --> 00:11:29,490 act on stages. They're on Earth in one 300 00:11:29,490 --> 00:11:30,230 g gravity, 301 00:11:31,264 --> 00:11:33,184 and it's just cheaper to to make their 302 00:11:33,184 --> 00:11:35,504 planets look like Earth. But even even written 303 00:11:35,504 --> 00:11:37,264 science fiction has fallen into that trap a 304 00:11:37,264 --> 00:11:38,945 little bit of having lots of Earth like 305 00:11:38,945 --> 00:11:41,024 planets. But of course, as I said, you 306 00:11:41,024 --> 00:11:42,625 need somewhere for your heroes to go. And 307 00:11:42,625 --> 00:11:44,980 if it's a barren cratered world, then you 308 00:11:44,980 --> 00:11:46,580 can't have as many adventures there as you 309 00:11:46,580 --> 00:11:48,660 could on on an Earth like planet. But 310 00:11:48,660 --> 00:11:50,419 one of the things that the science fiction 311 00:11:50,419 --> 00:11:53,059 writer Larry Niven liked to do was he 312 00:11:53,059 --> 00:11:53,720 would have 313 00:11:54,419 --> 00:11:57,139 niche planets where most of the planet was 314 00:11:57,139 --> 00:11:59,720 uninhabitable apart from one niche. 315 00:12:00,205 --> 00:12:02,845 So there was one, planet. So he had 316 00:12:02,845 --> 00:12:05,404 a lot of, I guess, there were, arch 317 00:12:05,404 --> 00:12:07,164 ships or or colony ships that would go 318 00:12:07,164 --> 00:12:10,205 out to planets that their robotic probes had 319 00:12:10,205 --> 00:12:11,105 said were habitable. 320 00:12:11,725 --> 00:12:14,205 So one of the, the ships arrives at 321 00:12:14,205 --> 00:12:14,865 this planet 322 00:12:15,819 --> 00:12:17,759 and finds it's all completely uninhabitable 323 00:12:18,139 --> 00:12:19,899 apart from the top of this one mountain 324 00:12:19,899 --> 00:12:21,659 that happens to peak up out of the 325 00:12:21,659 --> 00:12:23,740 clouds into a sort of a habitable area 326 00:12:23,740 --> 00:12:24,480 in the atmosphere. 327 00:12:25,179 --> 00:12:27,500 And they hadn't realized that their their robotic 328 00:12:27,500 --> 00:12:29,259 survey had just mapped that area and said, 329 00:12:29,259 --> 00:12:30,480 yeah. The planet's habitable. 330 00:12:31,235 --> 00:12:32,674 So they had to set up shop on 331 00:12:32,674 --> 00:12:33,735 on on this mountain. 332 00:12:34,434 --> 00:12:36,294 So it's this one niche. 333 00:12:37,154 --> 00:12:38,774 Other other Alastair Reynolds, 334 00:12:39,075 --> 00:12:41,475 is Sort of like a Goldilocks zone Yeah. 335 00:12:41,554 --> 00:12:43,714 Of a But within the planet. Yeah. Alastair 336 00:12:43,714 --> 00:12:45,955 Reynolds is a more more contemporary science fiction 337 00:12:45,955 --> 00:12:46,649 writer, was 338 00:12:48,250 --> 00:12:49,930 inspired by Larry Niven. And on one of 339 00:12:49,930 --> 00:12:52,090 his fictional planets, Yellowstone, the city is actually 340 00:12:52,090 --> 00:12:56,009 in a big gorge where there's, volcanic vents 341 00:12:56,009 --> 00:12:58,570 and and all kinds of gases coming out 342 00:12:58,570 --> 00:13:00,809 that can sustain an atmosphere just in in 343 00:13:00,809 --> 00:13:02,269 in that gorge, in that valley. 344 00:13:02,855 --> 00:13:04,294 And it may be that we find a 345 00:13:04,294 --> 00:13:06,154 lot of planets are mostly uninhabitable 346 00:13:06,855 --> 00:13:08,855 apart from certain areas. So that brings me 347 00:13:08,855 --> 00:13:11,754 on to Dune and the planet Arrakis. Now, 348 00:13:12,855 --> 00:13:13,355 Arrakis, 349 00:13:13,735 --> 00:13:16,375 Dune's my my favorite science fiction book of 350 00:13:16,375 --> 00:13:17,034 all time. 351 00:13:17,459 --> 00:13:20,100 And I'm sure many listeners saw the recent 352 00:13:20,100 --> 00:13:20,600 movies. 353 00:13:21,699 --> 00:13:22,199 And 354 00:13:22,980 --> 00:13:23,799 in June, 355 00:13:24,579 --> 00:13:26,419 the habitable it's a it's a desert planet 356 00:13:26,419 --> 00:13:27,860 as you can guess from the name. It's 357 00:13:27,860 --> 00:13:29,379 a desert planet, very hot, and the only 358 00:13:29,379 --> 00:13:30,519 habitable area 359 00:13:30,894 --> 00:13:33,375 in the story is at the poles. So 360 00:13:33,375 --> 00:13:35,134 they have the the capital city there, and 361 00:13:35,134 --> 00:13:38,975 and the Equator is practically uninhabitable except to 362 00:13:38,975 --> 00:13:40,355 the natives, the Fremen, 363 00:13:40,975 --> 00:13:43,454 and the big sandworms that that that move 364 00:13:43,454 --> 00:13:44,355 through the deserts. 365 00:13:45,200 --> 00:13:47,920 There was actually a study done by a 366 00:13:47,920 --> 00:13:50,340 climatologist actually here at the University of Bristol, 367 00:13:51,120 --> 00:13:52,980 Alex Farnsworth and his team. 368 00:13:53,600 --> 00:13:55,440 So they did a scientific model. Could a 369 00:13:55,440 --> 00:13:58,235 planet like Arrakis, this desert world, could it 370 00:13:58,235 --> 00:14:00,075 actually be real? We know, does it does 371 00:14:00,075 --> 00:14:02,174 it make sense from a a climate perspective? 372 00:14:02,794 --> 00:14:05,195 And it did, except they actually found that 373 00:14:05,195 --> 00:14:06,495 the habitable area 374 00:14:06,875 --> 00:14:08,554 would be at the Equator and that the 375 00:14:08,554 --> 00:14:10,235 way the climate and the atmosphere would work, 376 00:14:10,235 --> 00:14:12,735 it would make the the poles intolerably hot. 377 00:14:13,820 --> 00:14:17,200 And scientists actually think astronomers actually think that 378 00:14:17,740 --> 00:14:20,399 desert like worlds that are habitable may 379 00:14:21,259 --> 00:14:22,240 vastly outnumber 380 00:14:23,100 --> 00:14:25,500 our temperate earth like worlds that have just 381 00:14:25,500 --> 00:14:27,680 the right amount amount of land and sea. 382 00:14:28,845 --> 00:14:30,684 So so, you know, the planet in June 383 00:14:30,684 --> 00:14:31,825 could be a 384 00:14:32,605 --> 00:14:34,524 a forerunner to the kind of worlds that 385 00:14:34,524 --> 00:14:36,544 we might find that are barely habitable, 386 00:14:37,085 --> 00:14:39,325 but just about, and they may be really 387 00:14:39,325 --> 00:14:41,245 common in in the universe. Another kind of 388 00:14:41,245 --> 00:14:43,440 common planet would be an ocean planet that's 389 00:14:43,440 --> 00:14:43,940 completely 390 00:14:45,440 --> 00:14:45,940 drowned 391 00:14:46,399 --> 00:14:47,139 in ocean. 392 00:14:48,000 --> 00:14:48,980 Maybe with just 393 00:14:49,840 --> 00:14:51,600 little bits of land peeking out here and 394 00:14:51,600 --> 00:14:52,100 there. 395 00:14:52,480 --> 00:14:54,399 So they're like extremes of Earth, and the 396 00:14:54,399 --> 00:14:56,480 extremes may be more common than our finely 397 00:14:56,480 --> 00:14:58,075 balanced temperate planet. 398 00:14:58,455 --> 00:15:01,355 So, Keith, how's how science fiction writers 399 00:15:01,815 --> 00:15:02,315 portray 400 00:15:02,934 --> 00:15:04,394 exoplanets? Has that 401 00:15:05,014 --> 00:15:07,975 changed over the past few decades? I mean, 402 00:15:07,975 --> 00:15:10,710 you mentioned how HG Wells picked up on 403 00:15:10,710 --> 00:15:12,870 this idea that Mars could be older than 404 00:15:12,870 --> 00:15:13,370 Earth, 405 00:15:13,990 --> 00:15:17,509 and incorporated that into his fiction. But have 406 00:15:17,509 --> 00:15:20,070 have more contemporary writers, you know, let's say 407 00:15:20,070 --> 00:15:22,710 over the over the past three decades, have 408 00:15:22,710 --> 00:15:23,930 they picked up on 409 00:15:24,315 --> 00:15:26,394 on on discoveries? You know, for example, are 410 00:15:26,394 --> 00:15:29,674 they writing about life on hot Jupiters, for 411 00:15:29,674 --> 00:15:30,174 example? 412 00:15:30,634 --> 00:15:32,415 Absolutely. Oh, they're not hot Jupiters. 413 00:15:33,754 --> 00:15:35,915 There's a scarcity of hot Jupiters in in 414 00:15:35,915 --> 00:15:37,990 in the fiction, probably because you can't. It's 415 00:15:37,990 --> 00:15:39,430 hard to live there, and you'd have to 416 00:15:39,430 --> 00:15:42,149 be really imaginative to imagine life surviving in 417 00:15:42,149 --> 00:15:43,529 an atmosphere that reaches 418 00:15:44,070 --> 00:15:46,009 possibly up to 2,000 degrees Celsius. 419 00:15:47,670 --> 00:15:50,149 But you're right that the the writers are 420 00:15:50,149 --> 00:15:51,450 more tuned to, 421 00:15:52,149 --> 00:15:55,245 scientific research definitely incorporate that into their work, 422 00:15:55,245 --> 00:15:57,965 and they have done throughout the ages. You 423 00:15:57,965 --> 00:15:59,504 mentioned HG Wells there. 424 00:16:00,125 --> 00:16:01,745 Frank Herbert who wrote Dune, 425 00:16:02,524 --> 00:16:04,125 he got the idea for his book because 426 00:16:04,125 --> 00:16:05,100 he he was a journalist, 427 00:16:05,579 --> 00:16:07,259 and he was commissioned to write an article 428 00:16:07,259 --> 00:16:08,639 about Dunes in California. 429 00:16:09,659 --> 00:16:11,100 And that's where he got the idea from 430 00:16:11,100 --> 00:16:11,759 that form. 431 00:16:12,940 --> 00:16:16,000 There was another writer in, the fifty sixties 432 00:16:16,059 --> 00:16:16,559 called 433 00:16:18,299 --> 00:16:19,120 Hal Clement. 434 00:16:19,845 --> 00:16:21,524 He wrote a book called the, emission of 435 00:16:21,524 --> 00:16:23,205 gravity, which was set on a planet that 436 00:16:23,205 --> 00:16:24,345 has this crushing gravity. 437 00:16:24,804 --> 00:16:25,304 Theoretically, 438 00:16:25,764 --> 00:16:27,684 you know, it makes sense, but realistically, it 439 00:16:27,684 --> 00:16:29,924 probably wouldn't exist. But I actually had sent 440 00:16:29,924 --> 00:16:30,585 to me, 441 00:16:32,085 --> 00:16:32,970 the other week, 442 00:16:34,490 --> 00:16:36,409 by a chap in America, Jim Benford, who's 443 00:16:36,409 --> 00:16:38,750 the the science fiction writer, Gregory Benford's brother. 444 00:16:38,970 --> 00:16:40,809 He sent to me a PDF of an 445 00:16:40,809 --> 00:16:41,309 old, 446 00:16:41,929 --> 00:16:45,049 science fiction fan design from 1960 that had 447 00:16:45,049 --> 00:16:47,085 an essay by Hal Clement. And it was, 448 00:16:47,725 --> 00:16:48,865 about a new fictional 449 00:16:49,245 --> 00:16:51,965 planetary system that he'd invented for a novel 450 00:16:51,965 --> 00:16:53,085 he was going to write. We don't think 451 00:16:53,085 --> 00:16:54,524 he ever actually got around to writing the 452 00:16:54,524 --> 00:16:56,764 novel. But the the the system had this 453 00:16:56,925 --> 00:16:58,605 it was a binary star system, but it 454 00:16:58,605 --> 00:16:59,425 had a planet, 455 00:17:00,919 --> 00:17:03,160 had two planets. And one of the planets 456 00:17:03,160 --> 00:17:04,299 orbits came inside 457 00:17:05,240 --> 00:17:07,099 the other planets for a short time, 458 00:17:07,720 --> 00:17:10,220 very much like Neptune and Pluto. 459 00:17:10,680 --> 00:17:13,819 And Clement argued that that well, I you 460 00:17:13,960 --> 00:17:15,894 you said that this planet that came inside 461 00:17:15,894 --> 00:17:17,654 the other planet's orbit was actually used to 462 00:17:17,654 --> 00:17:19,174 be a moon of the other planet and 463 00:17:19,174 --> 00:17:21,434 it had escaped. And that was the theory 464 00:17:21,815 --> 00:17:24,134 regarding Pluto and Neptune at the time. A 465 00:17:24,134 --> 00:17:25,815 lot of scientists thought Pluto used to be 466 00:17:25,815 --> 00:17:26,954 a a moon of Neptune 467 00:17:27,779 --> 00:17:30,500 and that it somehow escaped Neptune's gravity and 468 00:17:30,500 --> 00:17:32,019 and started wandering on the sun on its 469 00:17:32,019 --> 00:17:32,519 own. 470 00:17:32,900 --> 00:17:35,220 And that was around 1960. The the idea 471 00:17:35,220 --> 00:17:37,539 was was in vogue. So Clements was looking 472 00:17:37,539 --> 00:17:38,680 at the latest research 473 00:17:38,980 --> 00:17:41,799 and incorporating incorporating it into his ideas. 474 00:17:42,134 --> 00:17:43,515 More re more recently, 475 00:17:44,775 --> 00:17:47,434 I spoke to a researcher at the 476 00:17:48,134 --> 00:17:49,894 she's at the Open University now, but she 477 00:17:49,894 --> 00:17:51,914 was at Saint Andrews, Emma Purinan. 478 00:17:52,695 --> 00:17:55,195 And she recently did her PhD on 479 00:17:55,840 --> 00:17:57,460 pretty much the topic of my book, 480 00:17:57,840 --> 00:17:59,860 how exoplanets are portrayed 481 00:18:00,240 --> 00:18:02,160 in science fiction, and what we can learn 482 00:18:02,160 --> 00:18:03,299 from that to, 483 00:18:04,880 --> 00:18:06,900 you know, do better science outreach. 484 00:18:08,559 --> 00:18:09,539 And she 485 00:18:11,075 --> 00:18:12,375 raised the point that 486 00:18:12,914 --> 00:18:15,394 in the last sort of thirty years or 487 00:18:15,394 --> 00:18:15,894 so, 488 00:18:17,715 --> 00:18:19,715 it coincides with the fact that we've discovered 489 00:18:19,715 --> 00:18:22,355 exoplanets, but it's more of an awareness of 490 00:18:22,355 --> 00:18:22,755 the 491 00:18:24,059 --> 00:18:24,799 how damaging 492 00:18:25,740 --> 00:18:27,759 colonies were on Earth, colonialism. 493 00:18:28,779 --> 00:18:30,700 And she says that in a lot of 494 00:18:30,700 --> 00:18:32,159 more modern science fiction, 495 00:18:32,460 --> 00:18:34,559 there tends to be fewer exoplanets 496 00:18:35,819 --> 00:18:37,359 where they have civilizations 497 00:18:37,740 --> 00:18:39,875 that have been settled by Earth, where Earth 498 00:18:39,875 --> 00:18:42,515 has colonized these planets. Because there's a growing 499 00:18:42,515 --> 00:18:43,815 awareness of of how, 500 00:18:45,234 --> 00:18:47,255 detrimental colonialism was. 501 00:18:48,115 --> 00:18:50,615 So that's been incorporated more into modern fiction. 502 00:18:51,315 --> 00:18:51,815 Another, 503 00:18:53,210 --> 00:18:55,549 type of planet that we're finding more often, 504 00:18:56,970 --> 00:18:59,230 rocky planets around what we call m dwarfs. 505 00:18:59,529 --> 00:19:02,269 You may know them more as red dwarfs, 506 00:19:02,329 --> 00:19:04,329 not not the comedy show, but these are 507 00:19:04,329 --> 00:19:04,829 small 508 00:19:05,210 --> 00:19:05,710 cool 509 00:19:06,009 --> 00:19:08,054 red stars. It's like and they have scaled 510 00:19:08,054 --> 00:19:09,275 down planetary systems, 511 00:19:09,974 --> 00:19:12,154 where they're really close to their star. 512 00:19:13,015 --> 00:19:13,515 One, 513 00:19:14,134 --> 00:19:16,855 famous example is Trappist one, which has seven 514 00:19:16,855 --> 00:19:19,595 worlds all packed into the inner 10,000,000 515 00:19:19,654 --> 00:19:21,275 kilometers of of the system. 516 00:19:22,109 --> 00:19:23,890 And because they're so close, 517 00:19:24,750 --> 00:19:28,609 their rotation becomes synchronized with their orbital period, 518 00:19:29,150 --> 00:19:30,910 and they become what we call tidally locked. 519 00:19:30,910 --> 00:19:32,910 So they always show the same hemisphere to 520 00:19:32,910 --> 00:19:35,230 their star. Much like the moon always shows 521 00:19:35,230 --> 00:19:37,035 the same face to Earth. The moon is 522 00:19:37,035 --> 00:19:38,815 also tied a lot to our planet. 523 00:19:39,835 --> 00:19:40,335 So 524 00:19:40,955 --> 00:19:43,515 these are a a a new kind of 525 00:19:43,515 --> 00:19:45,595 world that we've really only started discovering in 526 00:19:45,595 --> 00:19:47,215 the past fifteen, twenty years. 527 00:19:47,994 --> 00:19:50,154 And we're still understanding whether they could be 528 00:19:50,154 --> 00:19:52,109 habitable at all, what the climates might be 529 00:19:52,109 --> 00:19:53,869 like on such a world that, you know, 530 00:19:53,869 --> 00:19:55,630 one side always faces us and the other 531 00:19:55,630 --> 00:19:58,029 side is an eternal night. You know, would 532 00:19:58,029 --> 00:19:59,869 the would the night side be always frozen? 533 00:19:59,869 --> 00:20:02,210 Could an atmosphere distribute enough heat around? 534 00:20:02,589 --> 00:20:04,430 And there was the science fiction writer, Charlie 535 00:20:04,430 --> 00:20:05,170 Jane Anders. 536 00:20:05,605 --> 00:20:06,664 She's a contemporary, 537 00:20:07,044 --> 00:20:08,565 writer. And she wrote a book, The City 538 00:20:08,565 --> 00:20:09,765 in the Middle of the Night, which was 539 00:20:09,765 --> 00:20:11,444 set on one of these worlds. And she 540 00:20:11,444 --> 00:20:12,345 spoke to scientists 541 00:20:12,884 --> 00:20:15,284 about, what life might be like on one 542 00:20:15,284 --> 00:20:17,524 of these planets. And she told me that 543 00:20:17,524 --> 00:20:18,585 as she was writing, 544 00:20:19,610 --> 00:20:22,830 the scientific understanding of these worlds actually changed 545 00:20:22,970 --> 00:20:24,330 while she was in the middle of writing 546 00:20:24,330 --> 00:20:27,130 it. And she was like, oh, well, I 547 00:20:27,130 --> 00:20:28,570 need to go back and start again. She 548 00:20:28,570 --> 00:20:29,630 thought, no, because 549 00:20:30,009 --> 00:20:32,090 I'm too far along in the story. And 550 00:20:32,090 --> 00:20:33,690 she did raise a good point that the, 551 00:20:33,690 --> 00:20:35,884 you know, the point of science fiction is 552 00:20:35,884 --> 00:20:37,884 to tell a story. It's not to be 553 00:20:37,884 --> 00:20:39,164 part of the national curriculum. 554 00:20:40,924 --> 00:20:42,605 But, yeah, you know, she was having to 555 00:20:42,605 --> 00:20:44,684 respond to scientific discoveries as they were being 556 00:20:44,684 --> 00:20:46,045 made. She was responding to that on the 557 00:20:46,045 --> 00:20:46,545 fly. 558 00:20:47,085 --> 00:20:48,785 So that, you know, 559 00:20:49,309 --> 00:20:50,210 the good writers 560 00:20:50,829 --> 00:20:52,829 who really swap up and and and and 561 00:20:52,829 --> 00:20:53,809 do their research, 562 00:20:55,470 --> 00:20:56,450 you know, present 563 00:20:56,829 --> 00:20:59,549 possibilities for planets that that could be true, 564 00:20:59,549 --> 00:21:01,230 that we could find these planets in in 565 00:21:01,230 --> 00:21:03,730 in the future because they're really well realized. 566 00:21:04,724 --> 00:21:06,325 And that's, you know, that's the power of 567 00:21:06,325 --> 00:21:07,944 science fiction. Before we discovered 568 00:21:08,644 --> 00:21:09,144 exoplanets, 569 00:21:09,605 --> 00:21:11,765 you know, science fiction was telling us what 570 00:21:11,765 --> 00:21:12,664 they could be like. 571 00:21:13,684 --> 00:21:15,125 Science fiction got a lot right. And we 572 00:21:15,125 --> 00:21:16,724 also found that truth is a lot stranger 573 00:21:16,724 --> 00:21:18,359 than fiction. So it's it's 574 00:21:18,920 --> 00:21:20,920 been a bit of both. Yeah. And that's 575 00:21:20,920 --> 00:21:22,920 that's what I'd I'd like to talk about 576 00:21:22,920 --> 00:21:24,519 now. If we if we could move back 577 00:21:24,519 --> 00:21:26,140 to to, you know, 578 00:21:26,679 --> 00:21:27,900 actual exoplanets. 579 00:21:28,759 --> 00:21:32,299 I mean, astronomers have discovered some really extraordinary 580 00:21:33,319 --> 00:21:33,819 systems, 581 00:21:34,345 --> 00:21:35,244 very unexpected. 582 00:21:35,704 --> 00:21:38,264 I suppose you've chatted a bit about those 583 00:21:38,264 --> 00:21:38,764 already. 584 00:21:39,464 --> 00:21:40,845 Do you have any favorites, 585 00:21:41,944 --> 00:21:44,684 amongst the the the many types of exoplanets 586 00:21:44,904 --> 00:21:46,365 that we know exist? 587 00:21:46,970 --> 00:21:49,130 Is there one exoplanet or a type of 588 00:21:49,130 --> 00:21:51,690 exoplanet that stands out for you as as 589 00:21:51,690 --> 00:21:52,830 being really interesting? 590 00:21:53,769 --> 00:21:55,630 I've thought about this question a lot. 591 00:21:56,490 --> 00:21:58,090 It's hard to say because we know so 592 00:21:58,090 --> 00:21:59,309 little about the exoplanets. 593 00:21:59,690 --> 00:22:01,130 As as I said, you know, we can 594 00:22:01,130 --> 00:22:02,029 we can measure 595 00:22:02,625 --> 00:22:04,625 how big they are. They're they're sized when, 596 00:22:04,865 --> 00:22:06,545 we see them transit in front of their 597 00:22:06,545 --> 00:22:07,984 star. That's one way that we can detect 598 00:22:07,984 --> 00:22:09,984 them. So when they move in front of 599 00:22:09,984 --> 00:22:11,664 their star, they block some of the star's 600 00:22:11,664 --> 00:22:13,825 light. And the bigger they add, the more 601 00:22:13,825 --> 00:22:15,984 light they block. So we can determine their 602 00:22:15,984 --> 00:22:16,484 size. 603 00:22:17,080 --> 00:22:18,840 We know the mass of some of them 604 00:22:18,840 --> 00:22:19,980 based on their gravitational 605 00:22:20,360 --> 00:22:23,080 how how their gravity tugs on their parent 606 00:22:23,080 --> 00:22:23,580 star. 607 00:22:25,160 --> 00:22:27,080 And that's about it. And we know how 608 00:22:27,080 --> 00:22:28,840 far from their star they are so we 609 00:22:28,840 --> 00:22:29,340 can 610 00:22:29,764 --> 00:22:32,484 estimate how warm they might be. So it's 611 00:22:32,484 --> 00:22:34,105 really hard to say, you know, 612 00:22:34,804 --> 00:22:36,964 people fell in love with the Pandora from 613 00:22:36,964 --> 00:22:39,605 the Avatar films, and that's a fully realized 614 00:22:39,845 --> 00:22:41,605 it's actually a moon, not not a planet, 615 00:22:41,605 --> 00:22:43,970 but we don't know anything like that about 616 00:22:43,970 --> 00:22:46,049 the exoplanets that we detected so far. So 617 00:22:46,049 --> 00:22:48,769 it's hard to to pick one specific one 618 00:22:48,769 --> 00:22:50,549 that you could say would be a favorite. 619 00:22:51,250 --> 00:22:53,589 I do find the planets around Proxima Centauri 620 00:22:53,649 --> 00:22:56,085 interesting. Proxima Centauri is the it's a red 621 00:22:56,085 --> 00:22:58,085 dwarf, but it's also the closest star to 622 00:22:58,085 --> 00:23:00,265 our sun. It's just 4.2 light years away. 623 00:23:00,404 --> 00:23:01,704 So its sheer proximity 624 00:23:02,085 --> 00:23:03,065 is quite tantalizing. 625 00:23:04,804 --> 00:23:05,625 There's also 626 00:23:06,484 --> 00:23:08,005 I give this as a kind of jokey 627 00:23:08,005 --> 00:23:09,544 answer to to this question. 628 00:23:10,244 --> 00:23:10,744 There 629 00:23:11,769 --> 00:23:13,470 are some planets that 630 00:23:14,329 --> 00:23:16,109 could be what we call carbon rich 631 00:23:16,970 --> 00:23:19,470 where they actually have more carbon than oxygen. 632 00:23:19,769 --> 00:23:21,609 That results in all the oxygen getting locked 633 00:23:21,609 --> 00:23:22,109 away 634 00:23:22,650 --> 00:23:23,849 in carbon dioxide and 635 00:23:24,664 --> 00:23:26,184 so you couldn't breathe any there'd been no 636 00:23:26,184 --> 00:23:27,865 oxygen free oxygen there to breathe, so you 637 00:23:27,865 --> 00:23:30,024 can actually live there. But because this 638 00:23:30,505 --> 00:23:32,524 theoretically, there could be so much carbon 639 00:23:32,984 --> 00:23:34,984 within the core of the planet, that carbon 640 00:23:34,984 --> 00:23:35,724 gets compressed. 641 00:23:36,424 --> 00:23:37,724 You could get a solid 642 00:23:38,089 --> 00:23:40,250 diamond within the a huge chunk of solid 643 00:23:40,250 --> 00:23:42,410 diamond, planet sized solid diamond in in the 644 00:23:42,410 --> 00:23:44,170 core of the planet. You know, the surface 645 00:23:44,170 --> 00:23:45,390 would be made of graphite. 646 00:23:48,250 --> 00:23:49,450 So just from the point of view of 647 00:23:49,450 --> 00:23:51,345 a planet made of diamonds, you'd be rich. 648 00:23:51,585 --> 00:23:53,184 So so I always give that as a 649 00:23:53,184 --> 00:23:54,565 jokey answer. And 650 00:23:55,105 --> 00:23:56,865 in regards to whether any planets like that 651 00:23:56,865 --> 00:23:59,025 really exist, we have found stars that are 652 00:23:59,025 --> 00:24:02,065 more carbon rich than oxygen rich. So given 653 00:24:02,065 --> 00:24:04,144 that a star and its planets formed from 654 00:24:04,144 --> 00:24:05,125 the same material, 655 00:24:05,505 --> 00:24:06,869 we'd expect any planets 656 00:24:07,269 --> 00:24:09,349 to orbit those stars to also be carbon 657 00:24:09,349 --> 00:24:09,849 rich. 658 00:24:10,789 --> 00:24:14,309 There was one system in particular called 55 659 00:24:14,309 --> 00:24:14,809 Cancri 660 00:24:15,750 --> 00:24:17,450 that is carbon rich. 661 00:24:18,069 --> 00:24:18,809 But now 662 00:24:19,465 --> 00:24:21,625 astronomers don't believe it's carbon rich enough to 663 00:24:21,625 --> 00:24:23,945 to create a diamond planet. But the potential 664 00:24:23,945 --> 00:24:24,765 is out there. 665 00:24:25,545 --> 00:24:27,725 You know, people talk about going mining asteroids. 666 00:24:27,785 --> 00:24:29,945 Well, imagine mining a car a a carbon 667 00:24:29,945 --> 00:24:31,485 rich planet with all the diamond. 668 00:24:32,049 --> 00:24:33,490 Yeah. Well, I think what if if you 669 00:24:33,490 --> 00:24:36,049 did find an entire planet made of diamond, 670 00:24:36,049 --> 00:24:38,950 maybe the the value of diamond would plummet. 671 00:24:39,650 --> 00:24:42,609 Yes. Exactly. Yes. You'd you'd saturate the market, 672 00:24:42,609 --> 00:24:43,190 I think. 673 00:24:44,295 --> 00:24:45,815 Yeah. That is I mean, I thought about 674 00:24:45,815 --> 00:24:47,335 it as well. And, you know, I I 675 00:24:47,335 --> 00:24:48,855 sort of have to go back to these 676 00:24:48,855 --> 00:24:50,795 hot Jupiters, you know, these huge 677 00:24:51,255 --> 00:24:53,575 gas giants that are very close to their 678 00:24:53,575 --> 00:24:54,075 stars. 679 00:24:54,615 --> 00:24:56,695 And, you know, I just can't work out 680 00:24:56,695 --> 00:24:59,309 in my mind. Because I suppose we have 681 00:24:59,309 --> 00:25:01,710 this vision of of Jupiter as being this 682 00:25:01,710 --> 00:25:04,849 very cold planet and icy, and, 683 00:25:05,789 --> 00:25:07,809 but and the fact that one can exist 684 00:25:08,430 --> 00:25:09,569 very, very close 685 00:25:09,869 --> 00:25:12,430 to to a star just blows my mind. 686 00:25:12,430 --> 00:25:14,654 It, you know, I suppose it rewrites how 687 00:25:14,654 --> 00:25:15,394 we understand 688 00:25:16,974 --> 00:25:19,875 planets and and and sort of the energy, 689 00:25:20,494 --> 00:25:23,295 exchanges between a star and its planets. You 690 00:25:23,295 --> 00:25:24,194 know, it's really, 691 00:25:24,575 --> 00:25:26,194 really interesting, I think. 692 00:25:26,680 --> 00:25:28,039 Well, let me blow your mind a little 693 00:25:28,039 --> 00:25:30,039 bit more with that because they're so close. 694 00:25:30,039 --> 00:25:32,039 As I mentioned earlier, the temperature of their 695 00:25:32,039 --> 00:25:33,820 cloud tops can reach 696 00:25:34,440 --> 00:25:37,099 a thousand degrees Celsius, 2,000 degrees Celsius. 697 00:25:37,880 --> 00:25:39,500 When things get hot, they expand. 698 00:25:39,845 --> 00:25:41,464 So these planets are bloated. 699 00:25:41,924 --> 00:25:43,445 You know, they might have half the mass 700 00:25:43,445 --> 00:25:44,105 of Jupiter, 701 00:25:44,565 --> 00:25:47,144 but they're like three times as big. And 702 00:25:47,285 --> 00:25:48,664 because they're so expanded, 703 00:25:49,684 --> 00:25:52,244 gravity is holding on to their atmosphere very 704 00:25:52,244 --> 00:25:54,259 tenuously, and the the wind from the star, 705 00:25:54,259 --> 00:25:55,940 the wind of radiation from the star, like 706 00:25:55,940 --> 00:25:58,500 the solar wind, is blowing the atmosphere away. 707 00:25:58,500 --> 00:26:00,900 And they have tails like comets. And these 708 00:26:00,900 --> 00:26:03,220 tails are made from, you know, all all 709 00:26:03,220 --> 00:26:05,299 the metals and the hydrogen from from the 710 00:26:05,299 --> 00:26:05,799 atmosphere. 711 00:26:07,194 --> 00:26:08,654 And they're literally evaporating 712 00:26:08,954 --> 00:26:10,654 in front of our eyes. It's remarkable. 713 00:26:11,115 --> 00:26:13,034 So if you, you know, let's say, if 714 00:26:13,034 --> 00:26:15,274 you lived on a on a planet in 715 00:26:15,274 --> 00:26:17,454 that system, let's say a rocky planet 716 00:26:17,914 --> 00:26:20,319 a bit further out, what you would see 717 00:26:20,319 --> 00:26:21,139 in the sky 718 00:26:21,599 --> 00:26:24,319 would be amazing, wouldn't it, if you saw 719 00:26:24,319 --> 00:26:25,139 both this 720 00:26:25,440 --> 00:26:26,740 huge gas giant 721 00:26:27,200 --> 00:26:29,779 and the star as well. It would be 722 00:26:30,000 --> 00:26:31,599 it would be something else, wouldn't it? I 723 00:26:31,599 --> 00:26:33,220 mean, particularly when the star 724 00:26:33,875 --> 00:26:36,934 went below the horizon, but that gas giant 725 00:26:36,994 --> 00:26:39,575 was still there probably glowing in a big 726 00:26:39,634 --> 00:26:41,075 a big tail. And, 727 00:26:41,714 --> 00:26:43,875 yeah, it is it is mind blowing, isn't 728 00:26:43,875 --> 00:26:45,654 it? It is. To think about it. 729 00:26:46,274 --> 00:26:47,254 It it is. And 730 00:26:47,980 --> 00:26:50,159 the only caveat to that is because when 731 00:26:50,380 --> 00:26:52,079 because hot hot Jupiter's migrate 732 00:26:53,179 --> 00:26:55,179 from further out into, you know, really close 733 00:26:55,179 --> 00:26:57,179 to their star. Sometimes they collide with with 734 00:26:57,179 --> 00:26:59,339 with their star. But because they migrate in, 735 00:26:59,339 --> 00:27:00,940 any smaller worlds in the way just get 736 00:27:00,940 --> 00:27:02,539 kicked out. Some get kicked into the star. 737 00:27:02,539 --> 00:27:05,174 Some get ejected from the planetary system altogether. 738 00:27:05,315 --> 00:27:08,034 So it was thought that hot Jupiters would 739 00:27:08,034 --> 00:27:08,534 be 740 00:27:09,634 --> 00:27:10,774 like a single child. 741 00:27:12,914 --> 00:27:14,274 That's starting to change a little bit. We 742 00:27:14,274 --> 00:27:16,194 have started to find a couple of other 743 00:27:16,194 --> 00:27:16,694 planets 744 00:27:17,019 --> 00:27:18,640 that coexist with hot Jupiters. 745 00:27:19,980 --> 00:27:22,140 How that is so, we we don't entirely 746 00:27:22,140 --> 00:27:24,480 know. But, yeah, it it it you know, 747 00:27:25,339 --> 00:27:27,179 depending on how close your planet is to 748 00:27:27,179 --> 00:27:28,380 the star and the hot Jupiter, you can 749 00:27:28,380 --> 00:27:29,920 have many more total eclipses 750 00:27:30,304 --> 00:27:31,444 or partial eclipses. 751 00:27:32,304 --> 00:27:34,065 And, yeah, and there's a huge tail stretching 752 00:27:34,065 --> 00:27:35,044 across the sky. 753 00:27:35,984 --> 00:27:36,804 It would be 754 00:27:37,105 --> 00:27:37,605 remarkable. 755 00:27:38,625 --> 00:27:39,125 Yeah. 756 00:27:39,505 --> 00:27:40,724 Definitely something else. 757 00:27:41,984 --> 00:27:45,009 And and what about fictional exoplanets, Keith? I 758 00:27:45,009 --> 00:27:46,789 mean, you've mentioned a few already. 759 00:27:47,250 --> 00:27:50,070 But is there, is there a favorite imaginary 760 00:27:50,369 --> 00:27:51,350 world of yours? 761 00:27:51,890 --> 00:27:53,350 Endor because of the Ewoks. 762 00:27:54,529 --> 00:27:55,269 No. Joking. 763 00:27:57,464 --> 00:27:59,065 I'll answer this from the scientific point of 764 00:27:59,065 --> 00:28:00,525 view of which ones I think 765 00:28:01,785 --> 00:28:03,785 have the most to say about science and 766 00:28:03,785 --> 00:28:05,625 which I found most interesting to write about 767 00:28:05,625 --> 00:28:07,724 in my book, Amazing World. So I mentioned 768 00:28:07,945 --> 00:28:09,085 Dune and Arrakis. 769 00:28:11,630 --> 00:28:12,930 Another planet was 770 00:28:13,470 --> 00:28:14,769 the world of Gethen, 771 00:28:15,150 --> 00:28:17,009 which was in Ursula K. Le Guin's, 772 00:28:18,349 --> 00:28:20,190 award winning novel, The Left Hand of Darkness 773 00:28:20,190 --> 00:28:21,570 from 1969. 774 00:28:21,950 --> 00:28:23,410 This is an icy planet 775 00:28:24,215 --> 00:28:24,715 with 776 00:28:25,575 --> 00:28:27,335 a habitable strip. So we're going back to 777 00:28:27,335 --> 00:28:29,335 the niches again. This habitable strip around the 778 00:28:29,335 --> 00:28:29,835 equator 779 00:28:30,295 --> 00:28:32,134 where, you know, it gets to five degrees, 780 00:28:32,134 --> 00:28:33,654 10 degrees. It's a bit chilly, but you 781 00:28:33,654 --> 00:28:35,015 can you can live there. And then it's 782 00:28:35,015 --> 00:28:37,095 just these huge ice caps that almost meet 783 00:28:37,095 --> 00:28:37,835 at the Equator. 784 00:28:39,400 --> 00:28:39,900 And 785 00:28:41,160 --> 00:28:42,380 in the novel, 786 00:28:42,839 --> 00:28:44,619 she suggests that 787 00:28:45,480 --> 00:28:46,380 is connected 788 00:28:47,799 --> 00:28:49,019 to stellar activity. 789 00:28:49,559 --> 00:28:52,244 And she even refers to that the planet 790 00:28:52,244 --> 00:28:54,585 will always be like that because of volcanism, 791 00:28:55,125 --> 00:28:56,424 which is absolutely correct. 792 00:28:56,805 --> 00:28:58,265 Volcanoes act as 793 00:28:58,644 --> 00:28:58,884 Earth's, 794 00:29:01,285 --> 00:29:01,785 thermostat. 795 00:29:02,325 --> 00:29:04,644 You have the the the carbon silicate cycle. 796 00:29:04,644 --> 00:29:07,339 So as we know, to our detriment, carbon 797 00:29:07,339 --> 00:29:09,819 dioxide is a greenhouse gas. It warms the 798 00:29:09,819 --> 00:29:10,319 planet. 799 00:29:12,299 --> 00:29:15,119 At the moment, we're undergoing climate change through 800 00:29:15,740 --> 00:29:18,859 artificially dumping tons of of carbon dioxide and 801 00:29:18,859 --> 00:29:21,034 other greenhouse gases into the atmosphere. But, you 802 00:29:21,034 --> 00:29:23,274 know, it exists there naturally. And without it, 803 00:29:23,274 --> 00:29:24,255 Earth would freeze. 804 00:29:25,194 --> 00:29:27,054 I think, you know, the carbon gets cycled, 805 00:29:27,115 --> 00:29:28,414 it gets rained out, 806 00:29:28,714 --> 00:29:29,934 goes into the ocean, 807 00:29:30,474 --> 00:29:31,214 is incorporated 808 00:29:31,595 --> 00:29:34,075 into into life that that that dies, sinks 809 00:29:34,075 --> 00:29:35,700 to the bottom, the carbon gets, 810 00:29:36,740 --> 00:29:39,480 sequestrated into into, you know, in into 811 00:29:41,139 --> 00:29:41,720 the mantle, 812 00:29:42,579 --> 00:29:45,480 and eventually spat back out through volcanoes. So 813 00:29:45,700 --> 00:29:47,220 you go through periods where you've got a 814 00:29:47,220 --> 00:29:49,139 lot of carbon dioxide in the atmosphere and 815 00:29:49,139 --> 00:29:51,000 not so much. And and that regulates 816 00:29:51,434 --> 00:29:51,934 climate 817 00:29:52,634 --> 00:29:54,794 over tens of thousands of years. That it's 818 00:29:54,794 --> 00:29:56,494 like our our planetary thermostat. 819 00:29:57,434 --> 00:29:58,335 So so 820 00:29:58,714 --> 00:30:00,875 Le Guin was absolutely right that, you know, 821 00:30:00,875 --> 00:30:01,774 that would eventually 822 00:30:02,474 --> 00:30:04,714 warm her planet of Gethin and and the 823 00:30:04,714 --> 00:30:05,934 ice caps would retreat. 824 00:30:06,980 --> 00:30:08,519 But what's interesting about it 825 00:30:08,980 --> 00:30:11,220 is Earth has also gone through what we 826 00:30:11,220 --> 00:30:13,880 call it snowball phases at least twice before. 827 00:30:14,580 --> 00:30:16,920 Almost the entire planet was covered in ice. 828 00:30:17,619 --> 00:30:19,539 Yeah. It didn't wipe out life clearly. We're 829 00:30:19,539 --> 00:30:20,279 still here. 830 00:30:20,855 --> 00:30:21,674 And we've 831 00:30:22,455 --> 00:30:25,015 research has shown that it's possible that even 832 00:30:25,015 --> 00:30:26,215 though the ice could reach all the way 833 00:30:26,215 --> 00:30:27,195 down to the Equator, 834 00:30:27,734 --> 00:30:30,375 atmospheric circulation may mean that there's certain areas 835 00:30:30,375 --> 00:30:32,375 that don't freeze over and remain habitable. So 836 00:30:32,375 --> 00:30:33,434 we, again, the niches. 837 00:30:34,230 --> 00:30:35,369 So I just thought 838 00:30:36,309 --> 00:30:38,009 Le Guin there was really, 839 00:30:40,630 --> 00:30:43,509 really smart in in in understanding what makes 840 00:30:43,509 --> 00:30:44,970 plan planets and climates 841 00:30:45,430 --> 00:30:45,930 tick. 842 00:30:48,444 --> 00:30:50,444 So, yeah, I really enjoyed reading about that 843 00:30:50,444 --> 00:30:52,204 planet and and and writing about it because 844 00:30:52,204 --> 00:30:53,184 it was so clever. 845 00:30:53,805 --> 00:30:55,484 Wow. Yeah. I mean, I think for me, 846 00:30:55,484 --> 00:30:56,785 you know, I think the 847 00:30:57,244 --> 00:30:59,644 going back to Star Trek, you know, I 848 00:30:59,644 --> 00:31:01,105 I grew up in the seventies, 849 00:31:01,450 --> 00:31:03,450 and there wasn't much on TV back then, 850 00:31:03,450 --> 00:31:05,210 but there are lots of repeats of Star 851 00:31:05,210 --> 00:31:05,710 Trek. 852 00:31:06,090 --> 00:31:06,490 And, 853 00:31:07,450 --> 00:31:09,769 I mean, almost every episode, they went down 854 00:31:09,769 --> 00:31:12,350 to a planet which, you know, looked suspiciously 855 00:31:12,730 --> 00:31:13,869 like Southern California. 856 00:31:14,634 --> 00:31:16,554 But the the one episode I think, you 857 00:31:16,554 --> 00:31:18,174 know, I think that really struck me, 858 00:31:18,634 --> 00:31:20,634 it was when they went to a a 859 00:31:20,634 --> 00:31:22,414 a planet that was being mined, 860 00:31:23,275 --> 00:31:25,855 and they they sort of encountered this 861 00:31:26,154 --> 00:31:26,519 this 862 00:31:28,039 --> 00:31:30,299 life form that was burrowing through 863 00:31:30,680 --> 00:31:32,920 the rock. And, you know, it was, 864 00:31:33,640 --> 00:31:35,660 what did they describe it as? A silicon 865 00:31:35,799 --> 00:31:37,259 based life form. 866 00:31:37,559 --> 00:31:39,640 And I thought, you know, I thought that 867 00:31:39,640 --> 00:31:41,825 was really, you know, it it sort of 868 00:31:41,825 --> 00:31:43,825 dawned on me then that, yes, you know, 869 00:31:43,825 --> 00:31:45,744 you could of course, life here on Earth 870 00:31:45,744 --> 00:31:46,884 is carbon based, 871 00:31:47,744 --> 00:31:49,904 but maybe somewhere else there would be silicon 872 00:31:49,904 --> 00:31:50,404 based, 873 00:31:51,585 --> 00:31:52,065 life. 874 00:31:52,945 --> 00:31:55,525 I don't know why that really that really 875 00:31:56,019 --> 00:31:58,900 stuck with me. And, you know, I'll never 876 00:31:58,900 --> 00:32:00,200 forget a few years ago. 877 00:32:00,900 --> 00:32:03,619 Matin, my colleague, here on Physics World, he 878 00:32:03,619 --> 00:32:04,119 went 879 00:32:05,059 --> 00:32:05,559 down, 880 00:32:06,740 --> 00:32:08,440 a mine in Yorkshire, 881 00:32:08,974 --> 00:32:11,714 the Bulby Mine, where they're, detecting, 882 00:32:14,414 --> 00:32:14,914 doing 883 00:32:16,335 --> 00:32:18,414 some experiments. I I I don't quite know 884 00:32:18,414 --> 00:32:20,174 the details. But I remember, you know, sort 885 00:32:20,174 --> 00:32:21,934 of laughing to myself that, you know, I 886 00:32:21,934 --> 00:32:22,255 hope, 887 00:32:22,849 --> 00:32:25,509 I hope Bettine doesn't encounter a potash based 888 00:32:25,730 --> 00:32:28,070 life form because it was a potash mine. 889 00:32:28,130 --> 00:32:29,730 You know, it's it just shows that, you 890 00:32:29,730 --> 00:32:32,309 know, forty years later, the the whole concept 891 00:32:33,410 --> 00:32:35,410 of going down a mine and encountering a 892 00:32:35,410 --> 00:32:35,910 strange 893 00:32:36,404 --> 00:32:39,205 life form, stuck with me. So it is 894 00:32:39,285 --> 00:32:41,045 I think it is very powerful, you know, 895 00:32:41,045 --> 00:32:41,785 this idea, 896 00:32:42,325 --> 00:32:45,144 both in fiction and in fact, of imagining 897 00:32:45,525 --> 00:32:46,025 alternative 898 00:32:47,045 --> 00:32:47,545 existences. 899 00:32:47,924 --> 00:32:48,244 And, 900 00:32:49,170 --> 00:32:50,769 I mean, I suppose in a sense it 901 00:32:50,769 --> 00:32:53,570 it it probably can be very useful here 902 00:32:53,570 --> 00:32:55,269 on Earth as well because 903 00:32:56,049 --> 00:32:56,769 if you're, 904 00:32:57,490 --> 00:32:59,269 you know, I suppose the famous incident 905 00:32:59,809 --> 00:33:01,910 or incidents here on Earth is 906 00:33:03,404 --> 00:33:06,845 the discovering that in those vents deep in 907 00:33:06,845 --> 00:33:07,505 the ocean 908 00:33:07,884 --> 00:33:09,984 that there actually can be life. 909 00:33:10,365 --> 00:33:11,984 And, of course, if, you know, 910 00:33:12,365 --> 00:33:14,625 if you're a if you're a biologist 911 00:33:15,179 --> 00:33:17,500 decades ago, you probably wouldn't have believed that 912 00:33:17,500 --> 00:33:19,259 because you would have thought, well, we have 913 00:33:19,259 --> 00:33:21,259 to have sunlight and, you know, we can't 914 00:33:21,259 --> 00:33:22,879 have all these toxic chemicals 915 00:33:23,339 --> 00:33:25,440 spewing out of the Earth. Those would immediately 916 00:33:25,500 --> 00:33:26,319 kill things. 917 00:33:26,779 --> 00:33:28,639 So, you know, I can see how 918 00:33:29,605 --> 00:33:30,105 reading 919 00:33:30,484 --> 00:33:31,704 fiction about exoplanets 920 00:33:32,005 --> 00:33:34,825 and studying them, that that could really help, 921 00:33:36,804 --> 00:33:40,085 scientists beyond physics and astronomy to to understand 922 00:33:40,085 --> 00:33:41,304 the world around us. 923 00:33:42,299 --> 00:33:43,179 So, yeah, it's, 924 00:33:44,299 --> 00:33:47,440 hopefully, some scientists will read, you know, biologists 925 00:33:47,819 --> 00:33:50,720 read your book and maybe be inspired about 926 00:33:50,859 --> 00:33:52,240 their views on life. 927 00:33:52,779 --> 00:33:54,319 I I I certainly hope so. 928 00:33:55,214 --> 00:33:56,974 The the Bulbimine, yeah, that's that's where the, 929 00:33:57,295 --> 00:33:58,974 the dark matter experiment that that I think 930 00:33:58,974 --> 00:34:00,575 they're looking for dark matter particles there. But 931 00:34:00,575 --> 00:34:02,255 just going back to the Star Trek episode, 932 00:34:02,974 --> 00:34:04,414 so that was the episode Devil in the 933 00:34:04,414 --> 00:34:04,914 Dark. 934 00:34:05,375 --> 00:34:07,410 And the yeah. It was a silicon based 935 00:34:07,650 --> 00:34:09,410 life form that was protect it it was 936 00:34:09,410 --> 00:34:10,070 the mother, 937 00:34:10,449 --> 00:34:12,449 the species was called the Horta. The Horta. 938 00:34:12,449 --> 00:34:14,630 Yeah. And and the mother was protecting, 939 00:34:15,010 --> 00:34:17,170 her eggs. So all you know, they when 940 00:34:17,170 --> 00:34:18,769 they realized in the end that the mother 941 00:34:18,769 --> 00:34:20,945 was was was killing the miners and but 942 00:34:20,945 --> 00:34:23,025 when Kirk and Spark realized what was happening, 943 00:34:23,025 --> 00:34:24,244 they made peace and, 944 00:34:24,625 --> 00:34:26,465 and the the heart started doing the mining 945 00:34:26,465 --> 00:34:27,285 for the miners. 946 00:34:27,905 --> 00:34:29,925 But yeah. Yeah. Silicon based life, 947 00:34:30,945 --> 00:34:32,085 it's been talked about. 948 00:34:32,809 --> 00:34:34,750 I from what I understand, 949 00:34:35,690 --> 00:34:36,989 the problem with silicon 950 00:34:37,369 --> 00:34:38,909 based life is is 951 00:34:39,769 --> 00:34:41,949 partly that carbon bonds with with 952 00:34:42,889 --> 00:34:45,130 other atoms to create, you know, organic molecules 953 00:34:45,130 --> 00:34:48,125 a lot better than than silicon does. And 954 00:34:48,125 --> 00:34:48,945 the metabolism 955 00:34:50,364 --> 00:34:52,605 using silicon rather than carbon would be a 956 00:34:52,605 --> 00:34:53,344 lot slower, 957 00:34:53,804 --> 00:34:54,945 I believe. 958 00:34:56,284 --> 00:34:58,619 So whether silicon life could exist, 959 00:34:59,900 --> 00:35:01,360 you know, it's quite speculative. 960 00:35:01,660 --> 00:35:04,000 But it it does go to show that, 961 00:35:04,140 --> 00:35:05,900 you know, we're so obsessed with finding Earth 962 00:35:05,900 --> 00:35:07,900 like worlds that can support life as we 963 00:35:07,900 --> 00:35:08,559 know it. 964 00:35:09,180 --> 00:35:10,860 But how do we know that life as 965 00:35:10,860 --> 00:35:11,474 we know it 966 00:35:12,994 --> 00:35:14,994 isn't the rare kind of life and the 967 00:35:14,994 --> 00:35:16,835 life as we don't know it is the 968 00:35:16,835 --> 00:35:18,295 more common type of life? 969 00:35:18,675 --> 00:35:20,994 And should we be looking at other kinds 970 00:35:20,994 --> 00:35:23,474 of exoplanets that could possibly support different kinds 971 00:35:23,474 --> 00:35:26,035 of life? But it's it's very speculative and, 972 00:35:26,035 --> 00:35:28,070 you know, but that's where science fiction comes 973 00:35:28,070 --> 00:35:30,730 in in in suggesting these ideas. And, 974 00:35:31,349 --> 00:35:33,050 as you say, scientists can 975 00:35:33,590 --> 00:35:34,090 maybe 976 00:35:34,949 --> 00:35:36,710 follow-up on them. And and they have. There's 977 00:35:36,710 --> 00:35:39,289 been there's been papers written about various 978 00:35:39,844 --> 00:35:41,224 planets in science fiction, 979 00:35:43,045 --> 00:35:44,264 a lot about Dune. 980 00:35:45,444 --> 00:35:45,944 So 981 00:35:46,565 --> 00:35:48,585 I I I think there's a a symbiosis 982 00:35:48,804 --> 00:35:50,324 there. And it can definitely be used for 983 00:35:50,324 --> 00:35:51,304 outreach because, 984 00:35:51,929 --> 00:35:53,769 let's face it, most people most members of 985 00:35:53,769 --> 00:35:55,769 the public know about exoplanets from science fiction 986 00:35:55,769 --> 00:35:57,769 from watching Star Wars or Star Trek or 987 00:35:57,769 --> 00:35:58,269 Avatar. 988 00:35:59,289 --> 00:36:00,349 So it is 989 00:36:00,730 --> 00:36:03,929 a really good promotional tool for exoplanet research 990 00:36:03,929 --> 00:36:04,589 that maybe 991 00:36:05,105 --> 00:36:06,644 exoplanet scientists could 992 00:36:07,105 --> 00:36:08,405 make use of more often. 993 00:36:08,864 --> 00:36:10,005 And and you mentioned, 994 00:36:10,464 --> 00:36:13,025 you know, ex existing telescopes, and there's lots 995 00:36:13,025 --> 00:36:16,065 of or hopefully, lots of new telescopes going 996 00:36:16,065 --> 00:36:16,804 to be commissioned 997 00:36:17,369 --> 00:36:19,769 in the future. So, I mean, at some 998 00:36:19,769 --> 00:36:21,710 point, you know, we will 999 00:36:22,089 --> 00:36:25,049 see or hopefully see a smoking gun for 1000 00:36:25,049 --> 00:36:26,969 some sort of life. I mean, who knows 1001 00:36:26,969 --> 00:36:29,449 when when that'll happen. Do you do you 1002 00:36:29,449 --> 00:36:30,255 think that, 1003 00:36:30,654 --> 00:36:32,574 you know, when when when we've got that 1004 00:36:32,574 --> 00:36:35,634 peer reviewed paper about life on another planet, 1005 00:36:36,574 --> 00:36:39,214 is that gonna change our perception of our 1006 00:36:39,214 --> 00:36:39,714 place 1007 00:36:40,174 --> 00:36:40,994 in the universe? 1008 00:36:41,694 --> 00:36:44,414 Or may maybe that perception has changed already 1009 00:36:44,414 --> 00:36:47,339 or beginning to change because of these thousands 1010 00:36:47,400 --> 00:36:48,139 of exoplanets 1011 00:36:48,440 --> 00:36:49,900 that we've discovered already. 1012 00:36:50,839 --> 00:36:52,940 You know what? I surprised myself with 1013 00:36:53,559 --> 00:36:55,400 what I decided my answer was going to 1014 00:36:55,400 --> 00:36:57,739 be to that. I don't think it will. 1015 00:36:58,839 --> 00:36:59,420 I think 1016 00:37:00,925 --> 00:37:03,085 I mean, chances are that any life we 1017 00:37:03,085 --> 00:37:04,545 find out there is gonna be microbial, 1018 00:37:05,405 --> 00:37:07,405 which isn't gonna excite anybody. It'll excite the 1019 00:37:07,405 --> 00:37:07,905 astrobiologists. 1020 00:37:09,484 --> 00:37:10,944 But, you know, that's not 1021 00:37:11,644 --> 00:37:13,800 not going to excite anybody, I don't think. 1022 00:37:14,280 --> 00:37:16,280 If we found an earth like world, even 1023 00:37:16,280 --> 00:37:17,800 if we couldn't tell whether there was actually 1024 00:37:17,800 --> 00:37:18,699 life on it, 1025 00:37:19,480 --> 00:37:21,800 again, it's so far away. We're not going 1026 00:37:21,800 --> 00:37:23,960 to be able to go there. So, you 1027 00:37:23,960 --> 00:37:26,199 know, after a few days of excitement, it's 1028 00:37:26,199 --> 00:37:27,960 gonna die down. People just gonna get on 1029 00:37:27,960 --> 00:37:29,739 with their lives and forget about it. 1030 00:37:30,305 --> 00:37:32,065 There's even an argument that, you know, if 1031 00:37:32,065 --> 00:37:34,644 SETI discovered a radio signal from another 1032 00:37:35,825 --> 00:37:37,684 species light years away, 1033 00:37:39,025 --> 00:37:41,105 that that wouldn't change anything because of the 1034 00:37:41,105 --> 00:37:43,260 distance. Unless unless they give us 1035 00:37:43,820 --> 00:37:44,320 knowledge 1036 00:37:44,780 --> 00:37:47,360 and technology that we couldn't have otherwise. 1037 00:37:48,219 --> 00:37:50,219 I don't know whether it would affect everyday 1038 00:37:50,219 --> 00:37:52,380 life. And at the end of the day, 1039 00:37:52,380 --> 00:37:54,699 people are more concerned about, you know, putting 1040 00:37:54,699 --> 00:37:55,760 dinner on the table, 1041 00:37:56,184 --> 00:37:58,344 you know, paying bills and and just enjoying 1042 00:37:58,344 --> 00:38:00,105 their life. And I I don't I don't 1043 00:38:00,105 --> 00:38:00,605 think 1044 00:38:01,944 --> 00:38:03,545 I I, you know, I'd hope it would, 1045 00:38:03,545 --> 00:38:05,065 and it should do, but I don't think 1046 00:38:05,065 --> 00:38:07,244 it would have that great an an effect. 1047 00:38:08,390 --> 00:38:10,010 I guess what could 1048 00:38:11,269 --> 00:38:12,410 have an effect 1049 00:38:13,030 --> 00:38:14,390 is if we go back to the nineteen 1050 00:38:14,390 --> 00:38:16,869 sixties and the first pictures of Earth from 1051 00:38:16,869 --> 00:38:17,369 space, 1052 00:38:17,670 --> 00:38:19,510 had a huge effect on on, you know, 1053 00:38:19,510 --> 00:38:21,510 the environmental movement at the time. And if 1054 00:38:21,510 --> 00:38:24,105 you can imagine a similar picture of an 1055 00:38:24,105 --> 00:38:24,605 exoplanet 1056 00:38:24,905 --> 00:38:28,445 with oceans and continents and forests and clouds 1057 00:38:28,505 --> 00:38:30,605 and and maybe life as well, 1058 00:38:31,704 --> 00:38:33,485 I think that could have a big effect. 1059 00:38:33,945 --> 00:38:35,864 Yeah. Because I'm I I suppose the thing 1060 00:38:35,864 --> 00:38:36,925 is, in a way, 1061 00:38:37,369 --> 00:38:39,949 this I this it's a very deeply entrenched 1062 00:38:40,010 --> 00:38:41,230 idea in 1063 00:38:41,769 --> 00:38:44,650 in people's minds, isn't it, through I I 1064 00:38:44,650 --> 00:38:47,210 suppose through fiction and art to a certain 1065 00:38:47,210 --> 00:38:48,969 extent. You know, if you if you've watched 1066 00:38:48,969 --> 00:38:50,269 all the Star Wars films, 1067 00:38:50,744 --> 00:38:52,284 if you watch Star Trek, 1068 00:38:52,744 --> 00:38:54,585 if you've read, you know, a bit of 1069 00:38:54,585 --> 00:38:55,804 science fiction, then 1070 00:38:56,184 --> 00:38:57,724 the idea is there already, 1071 00:38:58,184 --> 00:39:00,284 and it, you know, it doesn't seem crazy. 1072 00:39:01,704 --> 00:39:02,444 And so 1073 00:39:03,224 --> 00:39:04,444 learning about it, 1074 00:39:04,984 --> 00:39:06,329 learning that it's true, 1075 00:39:06,809 --> 00:39:08,250 you know, that I I don't think that 1076 00:39:08,250 --> 00:39:10,090 would blow blow Pina's minds. 1077 00:39:10,570 --> 00:39:11,769 I think I think there's an easy way 1078 00:39:11,769 --> 00:39:13,530 to test this. There's a lot of people 1079 00:39:13,530 --> 00:39:15,769 who believe in UFOs. I don't. But there's 1080 00:39:15,769 --> 00:39:16,809 a lot of people who do. And, you 1081 00:39:16,809 --> 00:39:19,465 know, when whenever there's a a discovery about 1082 00:39:19,465 --> 00:39:20,045 a biosignature 1083 00:39:20,425 --> 00:39:22,105 or, you know, possibility of life on the 1084 00:39:22,105 --> 00:39:24,184 planet, you get loads of people saying, we 1085 00:39:24,184 --> 00:39:26,204 already knew about that. They're already here. 1086 00:39:27,144 --> 00:39:29,784 So has life changed for them? You know, 1087 00:39:29,784 --> 00:39:31,565 how has their view of of 1088 00:39:32,425 --> 00:39:33,960 life and the universe changed 1089 00:39:34,440 --> 00:39:36,679 through thinking UFOs are real? I I don't 1090 00:39:36,679 --> 00:39:37,500 think it has. 1091 00:39:39,000 --> 00:39:41,639 I find UFOs very unimaginative to be true 1092 00:39:41,719 --> 00:39:42,219 truthful. 1093 00:39:43,400 --> 00:39:45,000 And you can tell that it hasn't really 1094 00:39:45,000 --> 00:39:46,460 changed their world view, 1095 00:39:46,839 --> 00:39:48,139 at least not for the better. 1096 00:39:48,775 --> 00:39:50,614 So I I I think that's quite an 1097 00:39:50,614 --> 00:39:52,934 interesting test case. We already have people who 1098 00:39:52,934 --> 00:39:54,775 are convinced there's alien life and that it's 1099 00:39:54,775 --> 00:39:56,375 here. And so how has it affected them? 1100 00:39:56,375 --> 00:39:57,195 And I don't 1101 00:39:58,054 --> 00:39:58,954 I don't think 1102 00:39:59,655 --> 00:40:01,409 it has too much other than just, 1103 00:40:02,609 --> 00:40:04,549 you know, making them believe there's big conspiracies. 1104 00:40:06,449 --> 00:40:08,449 Yeah. Well, I suppose that's the other problem, 1105 00:40:08,449 --> 00:40:09,250 isn't it? That, 1106 00:40:09,730 --> 00:40:11,650 you know, the way things are these days, 1107 00:40:12,049 --> 00:40:13,109 you know, the scientists 1108 00:40:13,409 --> 00:40:14,049 could announce, 1109 00:40:14,844 --> 00:40:16,844 that they found evidence for life and people 1110 00:40:16,844 --> 00:40:18,285 wouldn't believe them. But, 1111 00:40:19,805 --> 00:40:21,405 that's, you know, that's just the way the 1112 00:40:21,405 --> 00:40:23,565 modern world, or the world as it is 1113 00:40:23,565 --> 00:40:25,885 at the moment. Well thanks Keith, thanks so 1114 00:40:25,885 --> 00:40:26,605 much for, 1115 00:40:27,085 --> 00:40:29,265 coming on to the podcast and talking 1116 00:40:29,699 --> 00:40:32,359 about your book. And, I'll put a link 1117 00:40:32,579 --> 00:40:33,480 in the notes, 1118 00:40:34,099 --> 00:40:35,079 for the podcast, 1119 00:40:35,780 --> 00:40:36,599 to the book. 1120 00:40:36,980 --> 00:40:38,820 Thanks for coming in. Thank you for having 1121 00:40:38,820 --> 00:40:39,320 me. 1122 00:40:48,255 --> 00:40:50,175 I'm afraid that's all the time we have 1123 00:40:50,175 --> 00:40:51,074 for this episode. 1124 00:40:51,454 --> 00:40:54,755 Thanks to Keith Cooper for joining me today, 1125 00:40:55,054 --> 00:40:57,235 and a special thanks to our producer, 1126 00:40:57,614 --> 00:40:58,675 Fred Isles. 1127 00:40:59,269 --> 00:41:03,030 Keith's book is published by Reaction Books, and 1128 00:41:03,030 --> 00:41:03,769 it's called 1129 00:41:04,230 --> 00:41:08,650 Amazing Worlds of Science Fiction and Science Fact. 1130 00:41:09,269 --> 00:41:11,530 Look out for a link in the podcast 1131 00:41:11,829 --> 00:41:13,335 notes to the book. 1132 00:41:13,894 --> 00:41:15,755 We'll be back again next week. 1133 00:41:16,054 --> 00:41:16,954 See you then.