WEBVTT 1 00:00:00.000 --> 00:00:06.260 Good afternoon. Greetings to this session on extraterrestrial life in the Festival of Ideas. 2 00:00:06.340 --> 00:00:12.520 My name's Derek Abbott. I'm based here at Adelaide Uni in the Electrical Engineering Department just here. 3 00:00:12.680 --> 00:00:19.380 I'm also Director of the Centre for Biomedical Engineering, and it's my pleasure to chair today's session. 4 00:00:19.640 --> 00:00:25.000 So I'd like to begin by introducing our speaker, Seth Shostak. 5 00:00:25.000 --> 00:00:32.520 A little bit about Seth. He's got his BA in Physics from Princeton University in the USA. 6 00:00:33.120 --> 00:00:43.980 He then went on and did a PhD in Astronomy at Caltech in California, and he now works at the SETI Institute in California. 7 00:00:44.460 --> 00:00:50.920 SETI, for those of you who don't know what that stands for, stands for Search for Extraterrestrial Intelligence. 8 00:00:51.220 --> 00:00:52.200 Did I get that right? 9 00:00:54.000 --> 00:00:54.920 So there's... 10 00:00:55.000 --> 00:00:58.480 He's searching for intelligent life forms out in the universe. 11 00:00:59.840 --> 00:01:07.980 SETI is based in Mountain View in California, and Seth tells me that's right next door to Google, the people that do the search engines. 12 00:01:10.020 --> 00:01:16.000 So Seth's little joke is that there are now two search engines in Mountain View, California. 13 00:01:18.440 --> 00:01:23.220 Seth was also... It's not Seth's first time to Adelaide. He's been here before. 14 00:01:23.280 --> 00:01:24.880 In fact, he was here... 15 00:01:25.000 --> 00:01:26.820 Just this last December. 16 00:01:28.060 --> 00:01:35.460 And he went through Adelaide to Roxby Downs to watch the solar eclipse that was this December. 17 00:01:36.860 --> 00:01:46.360 And the photograph he took of the solar eclipse at Roxby Downs was actually ran in the New York Times. 18 00:01:46.480 --> 00:01:50.400 So the photographer that did the most... 19 00:01:51.380 --> 00:01:54.780 Got the photograph with the best coverage of Roxby Downs. 20 00:01:54.780 --> 00:01:56.920 In the world was this guy here. 21 00:01:58.020 --> 00:01:59.920 So that's one of his claims to fame. 22 00:02:01.260 --> 00:02:05.800 Also, another interesting connection he has with Australia is that... 23 00:02:05.800 --> 00:02:09.100 I don't know how many of you have watched the movie The Dish. 24 00:02:09.400 --> 00:02:15.220 For those of you who haven't seen the Australian movie The Dish, I recommend you go out and get the video today. 25 00:02:15.520 --> 00:02:16.620 It's about... 26 00:02:16.620 --> 00:02:17.920 It's a short... 27 00:02:17.920 --> 00:02:24.680 It's a film about the Australian radio astronomy dish that is in the park. 28 00:02:24.680 --> 00:02:26.400 It's called the Park's Observatory. 29 00:02:27.920 --> 00:02:30.540 And so it's a very famous movie. 30 00:02:30.920 --> 00:02:35.420 And Seth actually worked there in 1995 for a couple of months. 31 00:02:35.560 --> 00:02:38.040 So that's another connection he has with Australia. 32 00:02:38.340 --> 00:02:40.200 But I think I want to... 33 00:02:40.200 --> 00:02:42.680 I'm dying to hear his talk about extraterrestrials. 34 00:02:43.320 --> 00:02:46.660 So without further to do, can we put our hands together for him? 35 00:02:50.120 --> 00:02:52.900 You might want to tell him about the baby phone down here. 36 00:02:52.980 --> 00:02:54.600 There are all sorts of baby sounds coming out. 37 00:02:56.700 --> 00:03:01.720 Thank you very much, Derek, for a very flattering introduction. 38 00:03:01.860 --> 00:03:04.320 In fact, it reminds me of a comment made by Einstein. 39 00:03:04.440 --> 00:03:05.900 Not that I should compare myself to Einstein. 40 00:03:06.200 --> 00:03:07.580 At some point, which he said, 41 00:03:07.660 --> 00:03:09.740 Would it be a shame if the packaging were better than the meat? 42 00:03:11.840 --> 00:03:14.940 Anyhow, I'm told that you all have to be out of here by 5.30. 43 00:03:15.040 --> 00:03:22.840 So what I thought I would do is talk to you a little bit about why we think the aliens may be out there. 44 00:03:22.880 --> 00:03:24.000 How we're looking for them. 45 00:03:24.000 --> 00:03:25.640 What they might be like. 46 00:03:25.720 --> 00:03:28.040 In case you run across any in downtown Adelaide. 47 00:03:28.320 --> 00:03:31.080 And the title of the talk, of course, 48 00:03:31.200 --> 00:03:35.060 What it would mean to you, the car buyer, if we were to find them. 49 00:03:35.300 --> 00:03:40.340 And then I hope to open this up for questions so you can grill me like a cheese sandwich at the end. 50 00:03:40.460 --> 00:03:44.760 And ask all those questions you know that I am deliberately not dealing with. 51 00:03:45.280 --> 00:03:47.040 Dave's working on the AV here. 52 00:03:50.520 --> 00:03:51.580 There you go. 53 00:03:51.820 --> 00:03:52.260 Alright. 54 00:03:52.880 --> 00:03:53.620 Not too bad. 55 00:03:54.000 --> 00:03:58.560 I might say, by the way, that although Derek mentioned some of my connection to Australia, 56 00:03:58.700 --> 00:04:02.300 I should say that in some sense there's a far deeper connection to Australia. 57 00:04:02.420 --> 00:04:04.240 Because I don't know how many of you realize this, 58 00:04:04.380 --> 00:04:10.300 but Australia is one of the three or four countries in the forefront of the development of science, 59 00:04:10.480 --> 00:04:12.220 the science of radio astronomy. 60 00:04:12.880 --> 00:04:14.800 When I was a grad student at Caltech, in fact, 61 00:04:14.800 --> 00:04:18.880 the director of the Owens Valley Radio Observatory was an Australian, Gordon Stanley. 62 00:04:19.100 --> 00:04:23.660 But that observatory was actually built by the fellow who built the dish at Parkes, John Bolton. 63 00:04:23.660 --> 00:04:24.660 Another Australian. 64 00:04:25.040 --> 00:04:30.760 The Australians were, as I say, in the forefront of both building new equipment for this science 65 00:04:30.760 --> 00:04:33.860 and making the earliest and important scientific discoveries. 66 00:04:34.100 --> 00:04:36.260 So you have well reason to be proud of that. 67 00:04:36.700 --> 00:04:39.240 In any case, what happens when we find the aliens? 68 00:04:39.420 --> 00:04:39.620 Alright. 69 00:04:40.340 --> 00:04:43.500 The first question I would ask is, why do we think they're out there? 70 00:04:43.540 --> 00:04:44.800 Here you see them waiting for the bus. 71 00:04:46.080 --> 00:04:48.980 How many of you think that there are aliens out there? 72 00:04:49.020 --> 00:04:49.660 I'm just sort of curious. 73 00:04:49.860 --> 00:04:52.260 Because I know what the answer would be in the States, but I don't know here. 74 00:04:52.780 --> 00:04:55.320 And how many of you think, well, probably not? 75 00:04:56.760 --> 00:04:57.120 Okay. 76 00:04:57.160 --> 00:04:58.080 Well, that's interesting. 77 00:04:58.340 --> 00:04:59.660 That's maybe a fifth of the audience. 78 00:04:59.760 --> 00:05:01.340 You're the people I want to talk to later, of course. 79 00:05:03.860 --> 00:05:07.100 If you were to grab the next ten astronomers off the street of Adelaide, 80 00:05:07.180 --> 00:05:09.740 not a good idea, but if you were to do that and ask them, 81 00:05:10.180 --> 00:05:12.720 do you think that there might be aliens out there? 82 00:05:12.760 --> 00:05:14.780 I suspect nine out of ten would say yes. 83 00:05:15.920 --> 00:05:18.280 And they would say that not on the basis of personal experience, 84 00:05:18.420 --> 00:05:20.180 because there are no personal experiences. 85 00:05:20.180 --> 00:05:22.240 Well, there are plenty of personal experiences, but I'm not sure. 86 00:05:22.260 --> 00:05:23.540 They have anything to do with aliens. 87 00:05:23.640 --> 00:05:24.220 We'll get back to that. 88 00:05:24.380 --> 00:05:29.120 But they would say that on the basis of the fact, fundamentally, 89 00:05:29.380 --> 00:05:30.660 that the universe is quite vast. 90 00:05:31.080 --> 00:05:35.980 This is a picture of the night sky seen from downtown here during a rolling power blackout. 91 00:05:36.760 --> 00:05:38.420 And you can see the pointers and so on. 92 00:05:38.740 --> 00:05:44.140 I mean, obviously, with your eye, you can see several hundreds of nearby stars on a clear night. 93 00:05:44.240 --> 00:05:46.200 With a pair of binoculars, you can see thousands more. 94 00:05:46.800 --> 00:05:48.820 All of these stars, of course, are in our galaxy. 95 00:05:48.860 --> 00:05:52.240 I think enough of you know some elementary astronomy to be aware that, 96 00:05:52.260 --> 00:05:54.320 our galaxy is replete with stars. 97 00:05:54.520 --> 00:05:59.580 We have on the order of three or four hundred billion stars in our galaxy. 98 00:05:59.780 --> 00:06:04.600 And it turns out that roughly one in ten of those is very much like the sun, 99 00:06:04.720 --> 00:06:07.700 in terms of brightness and size and any other property you care to name. 100 00:06:08.020 --> 00:06:14.440 So, you know, we're one of forty or fifty billion stars like the sun in our galaxy. 101 00:06:14.540 --> 00:06:17.840 That's a big number, and that's not the end of the story, although you may wish that. 102 00:06:18.600 --> 00:06:22.240 This is a photo made by the Hubble Space Telescope about four or five years ago. 103 00:06:22.260 --> 00:06:25.380 And it's an unremarkable part of the sky. 104 00:06:25.540 --> 00:06:27.860 It's just a bit of the sky near the Big Dipper in the Northern Hemisphere. 105 00:06:28.800 --> 00:06:30.700 And it's actually a very small part of the sky. 106 00:06:31.060 --> 00:06:34.500 This is a bit of sky that you could cover up with a pinhead held at arm's length. 107 00:06:34.920 --> 00:06:38.700 All they did was expose the camera for about a hundred hours or something like that, 108 00:06:38.780 --> 00:06:40.460 and record very faint stuff. 109 00:06:40.640 --> 00:06:42.520 And there's some nearby stars here. 110 00:06:42.560 --> 00:06:44.540 You can see that spiky thing on the right and the left. 111 00:06:44.600 --> 00:06:45.420 Those are nearby stars. 112 00:06:45.880 --> 00:06:49.780 But those are the only stars, individual stars, in this picture. 113 00:06:50.080 --> 00:06:51.440 Everything else in this photo, 114 00:06:52.000 --> 00:06:52.960 is a galaxy. 115 00:06:53.120 --> 00:06:57.060 Those blobby things are all galaxies, each with several hundred billion stars. 116 00:06:57.740 --> 00:06:59.440 And of course there are a bunch of big blobs there, 117 00:06:59.500 --> 00:07:00.960 but there are also lots of small things here. 118 00:07:01.060 --> 00:07:03.740 These little guys, they're galaxies too. 119 00:07:03.900 --> 00:07:04.920 They're just farther away. 120 00:07:05.960 --> 00:07:09.180 Now, if you were to take photos like this across the entire sky, 121 00:07:09.980 --> 00:07:13.880 something for which the federal budget for NASA is not adequate, 122 00:07:14.020 --> 00:07:15.000 but if you were to do that, 123 00:07:15.500 --> 00:07:19.060 you would count approximately a hundred billion galaxies. 124 00:07:20.020 --> 00:07:21.420 Each with several hundred billion stars. 125 00:07:21.440 --> 00:07:23.380 So, you all being clever people, 126 00:07:23.500 --> 00:07:25.760 I'm sure you've multiplied those two numbers together in your head, 127 00:07:26.820 --> 00:07:28.700 perhaps on the back of the shirt of the guy in front of you. 128 00:07:28.940 --> 00:07:34.580 And that turns out to be a number that's 10,000 billion billion stars in the visible universe. 129 00:07:35.380 --> 00:07:38.540 And that may be a number that you don't use too often, except at tax time, 130 00:07:38.600 --> 00:07:44.020 but in fact, that is more stars visible to our telescopes 131 00:07:44.020 --> 00:07:47.160 than there are grains of sand on all the beaches of Australia. 132 00:07:48.740 --> 00:07:51.360 So, for the one out of five of you, 133 00:07:51.360 --> 00:07:54.020 in here who think, well, this is the only grain of sand 134 00:07:54.020 --> 00:07:56.000 where something interesting is happening, 135 00:07:56.920 --> 00:08:00.220 you have to say that's an audacious point of view, right? 136 00:08:01.420 --> 00:08:02.860 That would make you very special. 137 00:08:03.200 --> 00:08:05.140 And I know you think you're special, but you know. 138 00:08:05.360 --> 00:08:07.960 All right, well, let's look at this a little bit more carefully. 139 00:08:08.860 --> 00:08:13.580 Just because there are literally 10,000 billion billion stars in the universe, 140 00:08:13.920 --> 00:08:14.700 in the visible universe, 141 00:08:14.820 --> 00:08:16.940 there's much more to the universe than what we can see, of course. 142 00:08:18.480 --> 00:08:20.660 How many of those stars actually have planets? 143 00:08:20.660 --> 00:08:23.040 Because it's not good enough just to have a lot of stars. 144 00:08:23.320 --> 00:08:24.660 Life won't cook up on stars. 145 00:08:25.680 --> 00:08:26.680 Entirely too toasty. 146 00:08:27.300 --> 00:08:29.140 Now, it was thought for many years, 147 00:08:29.680 --> 00:08:31.820 at least for the last, oh, 30 or 40 years, 148 00:08:31.980 --> 00:08:34.040 that every time you made a star, 149 00:08:34.600 --> 00:08:36.740 you would have leftover crud, 150 00:08:36.820 --> 00:08:38.140 that's the technical term, 151 00:08:38.200 --> 00:08:39.460 that you would turn into planets. 152 00:08:40.040 --> 00:08:42.380 Okay, as you see in this simulation here. 153 00:08:42.680 --> 00:08:43.700 But that's theory. 154 00:08:44.740 --> 00:08:47.160 And in astronomy, theory doesn't count for very much, 155 00:08:47.260 --> 00:08:50.640 because astronomy has a very long history of being an observational science. 156 00:08:50.660 --> 00:08:53.760 So, you know, the theoreticians are generally ignored. 157 00:08:54.020 --> 00:08:57.000 They say, tell me something that I can prove by looking through the telescope. 158 00:08:57.880 --> 00:08:59.120 Well, the theoreticians are saying, 159 00:08:59.220 --> 00:09:00.580 well, there ought to be a lot of planets out there. 160 00:09:00.720 --> 00:09:03.280 And you might think, well, okay, we could easily prove that. 161 00:09:03.400 --> 00:09:05.120 We'll just take the Hubble telescope 162 00:09:05.120 --> 00:09:06.700 and aim it at some nearby stars 163 00:09:06.700 --> 00:09:07.980 and see if there are any planets around them. 164 00:09:08.600 --> 00:09:10.960 Good idea, but it doesn't work. 165 00:09:12.120 --> 00:09:14.400 And the reason it doesn't work is that planets are dim, 166 00:09:14.920 --> 00:09:15.820 kind of like my neighbors, 167 00:09:16.200 --> 00:09:18.900 and they're rather close to the stars that they orbit, 168 00:09:18.980 --> 00:09:20.640 so they're very difficult to find. 169 00:09:21.200 --> 00:09:22.720 They're like trying to find a moth 170 00:09:22.720 --> 00:09:25.860 circling a Hollywood searchlight from 10,000 miles away. 171 00:09:26.440 --> 00:09:27.600 Very difficult to do. 172 00:09:27.800 --> 00:09:31.320 And in fact, no planets had been found as recently as 1995. 173 00:09:31.700 --> 00:09:32.820 And then the story changed. 174 00:09:33.420 --> 00:09:36.540 It changed because astronomers figured out a way to find the planets 175 00:09:36.540 --> 00:09:37.720 without actually seeing them. 176 00:09:37.980 --> 00:09:41.340 You see there in the little animation a big planet going around a star. 177 00:09:42.140 --> 00:09:44.780 And the important thing is that the star doesn't just sit there 178 00:09:44.780 --> 00:09:50.440 while the planet nicely orbits it in some sort of elliptical orbit. 179 00:09:50.640 --> 00:09:53.700 The star dances too because of the motion of the planet. 180 00:09:54.020 --> 00:09:58.320 And it turns out that dance of the star is actually rather easier to find 181 00:09:58.320 --> 00:09:59.240 than the planet itself. 182 00:09:59.540 --> 00:10:01.500 And you see behind here some data. 183 00:10:02.700 --> 00:10:05.960 They say every time you show a plot like this you lose 10% of the audience. 184 00:10:06.300 --> 00:10:07.680 I have 12. 185 00:10:08.040 --> 00:10:10.260 So, in any case... 186 00:10:12.320 --> 00:10:15.860 But what you see here is just plotted the dance of a star 187 00:10:15.860 --> 00:10:17.160 by the name of 51 Pegasi, 188 00:10:17.260 --> 00:10:19.360 just a nearby star 40 or 50 light years away. 189 00:10:19.360 --> 00:10:21.420 And you see it comes at you at about what? 190 00:10:21.460 --> 00:10:22.300 50 meters a second. 191 00:10:22.360 --> 00:10:25.840 That's the speed at which you might drive your BMW down the Hume Highway 192 00:10:25.840 --> 00:10:28.080 on your way to Sydney or something for two days. 193 00:10:28.180 --> 00:10:30.980 And then it moves away from you at 50 meters per second. 194 00:10:31.020 --> 00:10:32.140 Then it comes toward you and moves away from you. 195 00:10:32.200 --> 00:10:33.000 It's dancing. 196 00:10:33.180 --> 00:10:33.780 It's dancing. 197 00:10:34.120 --> 00:10:36.620 And it's dancing because there's a planet going around it. 198 00:10:36.760 --> 00:10:40.660 So this was the first case in which they found a dancing star implying planets. 199 00:10:40.920 --> 00:10:44.200 We now know of something like 110 of these. 200 00:10:44.420 --> 00:10:46.080 And every couple of weeks there are a few more. 201 00:10:46.480 --> 00:10:46.880 Okay. 202 00:10:47.260 --> 00:10:49.340 In fact, the bottom line is that at least one in the world 203 00:10:49.360 --> 00:10:51.880 12% of the stars that we look at seem to have planets. 204 00:10:52.100 --> 00:10:52.620 One in eight. 205 00:10:53.340 --> 00:10:55.900 And the real percentage could be three in eight or seven in eight 206 00:10:55.900 --> 00:10:57.000 or maybe even eight in eight. 207 00:10:57.100 --> 00:11:02.020 We don't know because our instruments aren't adequate to find the smaller planets, 208 00:11:02.180 --> 00:11:03.020 the ones that are farther out. 209 00:11:03.180 --> 00:11:04.820 About a third of these are big guys. 210 00:11:05.020 --> 00:11:07.600 They're very big planets as you see here. 211 00:11:07.960 --> 00:11:11.240 A planet maybe the size of Jupiter very close into its star. 212 00:11:12.140 --> 00:11:14.100 Those are the so-called hot Jupiter planets. 213 00:11:14.400 --> 00:11:17.080 As I say, they constitute about a third of all that have been found. 214 00:11:17.160 --> 00:11:19.000 But it turns out that the instruments used 215 00:11:19.360 --> 00:11:21.540 to find these are better at finding those kinds of things. 216 00:11:21.740 --> 00:11:24.600 Those aren't the kind of planets E.T. would like to hang out on, by the way. 217 00:11:24.780 --> 00:11:27.160 Those of you who remember any high school physics can work out 218 00:11:27.160 --> 00:11:30.760 that the daytime temperatures on a planet like that are around 1,000 degrees. 219 00:11:32.180 --> 00:11:33.740 I don't remember whether that's centigrade or Fahrenheit, 220 00:11:33.920 --> 00:11:35.800 but when it's 1,000 degrees, what do you care? 221 00:11:36.600 --> 00:11:39.860 So that's, you know, obviously nothing's going to be living there. 222 00:11:40.160 --> 00:11:43.040 But where there are big planets, there might be small planets. 223 00:11:43.180 --> 00:11:46.900 And you might keep this mission in mind, the Kepler mission. 224 00:11:47.080 --> 00:11:49.040 This will be flown by NASA in the year 2000. 225 00:11:49.360 --> 00:11:51.960 And then in 2007, which lamentably isn't very far off, 226 00:11:52.120 --> 00:11:55.540 and that telescope will be able to find small planets. 227 00:11:55.900 --> 00:11:58.100 Planets the size of the Earth, the size of Mars, 228 00:11:58.240 --> 00:12:00.220 maybe even smaller, around other stars. 229 00:12:00.420 --> 00:12:03.140 This will be the first and only time in human history 230 00:12:03.140 --> 00:12:06.660 where we will do an inventory of the planets. 231 00:12:07.180 --> 00:12:12.000 When we will finally find what is the population of planets in the universe. 232 00:12:12.120 --> 00:12:13.700 This will all happen within your lifetime, of course. 233 00:12:13.780 --> 00:12:15.680 So this is kind of interesting stuff. 234 00:12:16.380 --> 00:12:16.820 Okay. 235 00:12:17.080 --> 00:12:19.060 Well, the bottom line of all that is that, 236 00:12:19.360 --> 00:12:21.880 it seems that planets are not particularly rare. 237 00:12:22.800 --> 00:12:23.820 So that's good news. 238 00:12:24.720 --> 00:12:26.060 But of course you need more than planets. 239 00:12:26.100 --> 00:12:27.540 You need life, if you're going to look for ET. 240 00:12:28.220 --> 00:12:30.700 And here you have life made out of ping pong balls and sticks. 241 00:12:31.120 --> 00:12:33.460 The question is, just because you have a lot of planets, 242 00:12:35.900 --> 00:12:38.300 a lot of planets cooking up primordial soup, 243 00:12:40.040 --> 00:12:42.140 which, by the way, was not a winner for Campbell's. 244 00:12:42.140 --> 00:12:42.960 They withdrew this thing. 245 00:12:44.460 --> 00:12:48.220 But in any case, you know, how many of them are going to cook up life, right? 246 00:12:48.220 --> 00:12:49.760 I mean, Fred Hoyle in Britain said, 247 00:12:49.880 --> 00:12:52.240 well, the chances that you'll cook up DNA 248 00:12:52.240 --> 00:12:55.320 just because you got a planet boiling away on its primordial soup 249 00:12:55.320 --> 00:12:58.360 is about the same as the chances that a tornado 250 00:12:58.360 --> 00:13:00.740 roaring through a junkyard would assemble a 747. 251 00:13:01.320 --> 00:13:03.600 And it turns out that that doesn't happen often. 252 00:13:03.740 --> 00:13:06.280 So what he was saying was that, you know, this isn't very likely. 253 00:13:07.460 --> 00:13:08.880 Well, not so clear. 254 00:13:10.060 --> 00:13:13.220 We could answer that question in one of two ways. 255 00:13:14.020 --> 00:13:15.680 Either we could finally try and understand, 256 00:13:15.800 --> 00:13:18.200 or we finally could understand how life got started, 257 00:13:18.220 --> 00:13:21.500 on Earth, something we still don't understand, by the way, 258 00:13:21.560 --> 00:13:23.420 but there's a lot of research done into that. 259 00:13:23.480 --> 00:13:25.400 If we could finally figure out how life got started on Earth, 260 00:13:25.520 --> 00:13:29.860 and if it were to turn out that that's a process that looks fairly commonplace, 261 00:13:30.080 --> 00:13:33.500 then we would expect that life would appear on similar planets elsewhere. 262 00:13:33.780 --> 00:13:37.400 The other way to find out whether life is common or not is to look for it. 263 00:13:37.640 --> 00:13:41.500 If we could find any kind of life anywhere else, 264 00:13:41.520 --> 00:13:45.200 not necessarily intelligent life, but some sort of pond scum, right, 265 00:13:45.320 --> 00:13:48.120 then perhaps that would tell you right away that, 266 00:13:48.220 --> 00:13:49.400 you know, that biology is fairly common. 267 00:13:49.480 --> 00:13:50.940 Well, the obvious place to look is Mars. 268 00:13:51.120 --> 00:13:52.860 People have been looking at Mars for a long time. 269 00:13:53.020 --> 00:13:56.400 In fact, this fellow, this is William Herschel, 270 00:13:56.480 --> 00:14:01.140 who was the organist at the Octagon Cathedral in Bath a couple of centuries ago. 271 00:14:01.240 --> 00:14:02.980 But he turned out to be King George Mad, 272 00:14:03.080 --> 00:14:06.700 King George's astronomer, after he gave up playing the organ there. 273 00:14:06.780 --> 00:14:11.000 He studied Mars, and he could see that Mars had these polar caps 274 00:14:11.000 --> 00:14:12.680 and these dark markings and so forth. 275 00:14:12.760 --> 00:14:14.540 He thought that Mars looked a lot like Earth, 276 00:14:14.660 --> 00:14:15.860 and he figured there might be Martians. 277 00:14:16.600 --> 00:14:19.240 That idea got a lot of credence in the 19th century, 278 00:14:19.860 --> 00:14:21.240 particularly thanks to this fellow. 279 00:14:22.140 --> 00:14:24.860 And he's probably not so well known here, but this is Percival Lowell. 280 00:14:25.520 --> 00:14:30.620 And he was born into a very wealthy Boston family in the 19th century. 281 00:14:30.660 --> 00:14:33.340 He didn't really have to worry about what he was going to do when he grew up, 282 00:14:33.400 --> 00:14:34.920 because he didn't have to do anything. 283 00:14:35.420 --> 00:14:38.500 But he was interested in astronomy, 284 00:14:39.120 --> 00:14:41.800 and he went to Harvard, got a degree in mathematics. 285 00:14:42.060 --> 00:14:43.960 He was a very clever guy, actually. He was a very smart guy. 286 00:14:44.380 --> 00:14:45.840 And rather than taking a degree in astronomy, 287 00:14:45.860 --> 00:14:48.560 he took a job in a fourth-rate university, hoping to get tenure after that. 288 00:14:48.640 --> 00:14:51.140 He said, to heck with that. I'll just build my own observatory. 289 00:14:51.140 --> 00:14:53.420 We've got the money. So he did. 290 00:14:54.120 --> 00:14:56.180 He built it in Flagstaff, Arizona, 291 00:14:56.400 --> 00:14:58.460 where people told him the atmosphere was nice and stable, 292 00:14:58.560 --> 00:15:00.480 so he would have good seeing. 293 00:15:01.080 --> 00:15:04.640 And he modestly named this edifice the Lowell Observatory. 294 00:15:05.240 --> 00:15:09.020 And spent many years using a telescope there to study Mars. 295 00:15:09.140 --> 00:15:12.760 And in particular, he claimed that he could see thin, straight lines 296 00:15:12.760 --> 00:15:14.280 crisscrossing the Martian surface. 297 00:15:15.060 --> 00:15:16.340 The canals of Mars. 298 00:15:18.640 --> 00:15:22.300 Now, he believed in these canals till his death in 1916. 299 00:15:22.400 --> 00:15:23.600 He mapped about 400 of them. 300 00:15:23.720 --> 00:15:27.540 You might wonder, by the way, why the Martians were engaged in all this civil engineering. 301 00:15:28.820 --> 00:15:30.560 Why they didn't invent railroads. 302 00:15:30.860 --> 00:15:34.340 But it turns out that Lowell had an answer to that. 303 00:15:34.400 --> 00:15:38.320 He said, look, Mars is a dying, drying planet. 304 00:15:38.420 --> 00:15:39.140 It's going bad. 305 00:15:39.720 --> 00:15:42.340 And the Martians, and he had no doubt there were Martians, 306 00:15:42.420 --> 00:15:44.260 the Martians are compelled to dig these canals. 307 00:15:44.280 --> 00:15:49.580 To bring water from the polar caps down to the equatorial regions 308 00:15:50.040 --> 00:15:53.820 where they would grow their Brussels sprouts or whatever else it was that they chowed down on. 309 00:15:54.140 --> 00:15:55.680 He wrote this up in a series of books. 310 00:15:55.800 --> 00:15:57.580 He was a good writer in addition to everything else. 311 00:15:57.660 --> 00:15:58.580 And the public believed it. 312 00:15:59.940 --> 00:16:02.520 And so here, the baby phone still works. 313 00:16:02.580 --> 00:16:03.380 I'm not quite sure what the deal is. 314 00:16:07.060 --> 00:16:09.400 Of course, in 1900, where was I? It doesn't matter. 315 00:16:10.420 --> 00:16:10.780 . 316 00:16:11.260 --> 00:16:11.580 . 317 00:16:14.580 --> 00:16:19.160 In 1900, of course, you would put on a suit and a tie to sit alone all night in a dark dome, 318 00:16:19.260 --> 00:16:19.900 you know, looking at Mars. 319 00:16:20.960 --> 00:16:21.280 . 320 00:16:21.280 --> 00:16:23.160 I say that because of what I've done here. 321 00:16:23.260 --> 00:16:26.940 But in fact, and he married rather late in life. 322 00:16:26.980 --> 00:16:29.320 He married at the age of 53 some woman, Constance. 323 00:16:29.360 --> 00:16:30.260 She was 14 or something. 324 00:16:30.380 --> 00:16:30.680 . 325 00:16:31.420 --> 00:16:34.800 And she apparently didn't find this all that interesting, so she remained back in Boston. 326 00:16:35.140 --> 00:16:35.460 . 327 00:16:35.460 --> 00:16:38.540 We don't have any photos of what she was doing in the evening, but presumably not this. 328 00:16:38.540 --> 00:16:38.800 . 329 00:16:40.280 --> 00:16:43.100 This would have been astounding if it were true, but it's not true. 330 00:16:43.180 --> 00:16:44.200 These were all optical illusions. 331 00:16:44.440 --> 00:16:46.080 In fact, this is what Mars really looks like. 332 00:16:46.320 --> 00:16:50.540 And when photos like this were shown to Lyndon Johnson, U.S. President, in the 1960s, 333 00:16:51.120 --> 00:16:54.680 when NASA first had good photos of Mars, his first reaction was, 334 00:16:54.800 --> 00:16:55.940 but where are the canals? 335 00:16:56.020 --> 00:16:56.440 . 336 00:16:56.440 --> 00:16:58.740 Which is kind of a tribute to American science education. 337 00:16:59.160 --> 00:16:59.520 . 338 00:17:00.400 --> 00:17:01.840 There are no canals on Mars. 339 00:17:01.960 --> 00:17:08.180 But the interesting and almost ironic fact is that there once was water on the surface of Mars. 340 00:17:08.240 --> 00:17:08.420 . 341 00:17:08.540 --> 00:17:09.160 There's no doubt about it. 342 00:17:09.300 --> 00:17:12.220 This is a recent photo made of Mars. 343 00:17:12.400 --> 00:17:16.840 You see some old craters here, but you see that they have been streamlined, made tear-shaped, 344 00:17:16.980 --> 00:17:21.060 by the motion of some sort of liquid coming from the upper left to the lower right in this photo here. 345 00:17:21.180 --> 00:17:23.280 This is a photo made in the last month or two. 346 00:17:23.660 --> 00:17:24.420 Here's another one. 347 00:17:24.640 --> 00:17:29.280 You can see sort of a ridge of mountains there, again running from upper left to lower right, 348 00:17:29.380 --> 00:17:33.900 and places where what looks like a lake or an ocean on the right-hand side broke through, 349 00:17:35.020 --> 00:17:37.420 and eroded these gullies through there. 350 00:17:37.680 --> 00:17:37.920 . 351 00:17:38.540 --> 00:17:43.700 Clearly, there was a time when Mars was a kinder, gentler world, and perhaps, indeed, supported life. 352 00:17:44.380 --> 00:17:49.800 Well, that idea, of course, gained a lot of notoriety in 1996 when this rock, 353 00:17:50.480 --> 00:17:54.480 which has the sexy name ALH84001, was found in Antarctica. 354 00:17:54.600 --> 00:17:58.000 It's a rock about this size, and it comes from Mars. 355 00:17:58.620 --> 00:18:00.440 There's no doubt about that. That's not controversial. 356 00:18:00.900 --> 00:18:03.380 In fact, there's a little plate on the bottom that says, Made in Mars. 357 00:18:03.560 --> 00:18:03.840 . 358 00:18:03.840 --> 00:18:08.120 You know, this comes from Mars, on the basis of the composition, for those who really care. 359 00:18:08.560 --> 00:18:12.920 So this is a piece of Mars that was kicked off the red planet, you know, 13 million years ago, 360 00:18:12.940 --> 00:18:14.280 came to Earth, and we can analyze it. 361 00:18:14.960 --> 00:18:19.660 And it has been analyzed, and as you may recall from that big science news story of 1996, 362 00:18:20.060 --> 00:18:21.920 it was the biggest science news story of 1996, 363 00:18:22.280 --> 00:18:28.260 the claim of some NASA scientists and a guy at Stanford was that inside this rock were Martians. 364 00:18:28.940 --> 00:18:30.440 Like little Rodney here. 365 00:18:30.720 --> 00:18:31.160 . 366 00:18:31.160 --> 00:18:37.360 The claim is that little Rodney is a Martian, or was a Martian, three and a half billion years ago. 367 00:18:37.380 --> 00:18:38.580 He's kind of fossilized now. 368 00:18:40.000 --> 00:18:43.400 Now, this would be astoundingly interesting and important. 369 00:18:44.220 --> 00:18:47.320 And you might wonder why that would be, because little Rodney, clearly, even if he were alive, 370 00:18:47.500 --> 00:18:49.960 would probably not hold up his side of the conversation very well. 371 00:18:51.020 --> 00:18:51.380 . 372 00:18:51.800 --> 00:18:55.100 Look, if this is the best Mars can do, I don't need to have any feelings with it. 373 00:18:55.140 --> 00:19:00.680 But that's, in fact, rather myopic, because, in fact, if Mars had life, 374 00:19:00.680 --> 00:19:04.500 even very simple single-celled life, like you would see in this microscope photo here, 375 00:19:04.720 --> 00:19:08.340 that would tell you in an instant that life is not a miracle. 376 00:19:09.340 --> 00:19:11.160 Life is just a statistic. 377 00:19:12.360 --> 00:19:15.980 Life, biology, is as common as phone poles, right? 378 00:19:16.040 --> 00:19:18.720 Because if the next planet out had life, then there's going to be life everywhere. 379 00:19:19.300 --> 00:19:19.760 Okay. 380 00:19:20.080 --> 00:19:22.360 So this is an important thing to know. 381 00:19:22.440 --> 00:19:24.200 Unfortunately, this is very contentious evidence, 382 00:19:24.360 --> 00:19:29.740 and most people don't believe that little Rodney here is alive, ever was alive, is a fossil of any sort. 383 00:19:29.960 --> 00:19:30.420 . 384 00:19:30.680 --> 00:19:31.600 So the jury's still out on this. 385 00:19:31.920 --> 00:19:35.420 But here's another argument that might suggest that life is very common. 386 00:19:35.760 --> 00:19:38.220 This is a picture of Adelaide made four billion years ago, 387 00:19:39.260 --> 00:19:40.680 when it was more of a happening place. 388 00:19:41.220 --> 00:19:41.580 . 389 00:19:42.640 --> 00:19:43.000 . 390 00:19:43.880 --> 00:19:44.240 . 391 00:19:44.240 --> 00:19:50.580 I want to say that the crew here said be sure to insult the audience. 392 00:19:50.680 --> 00:19:51.260 They like that. 393 00:19:51.460 --> 00:19:51.760 . 394 00:19:53.040 --> 00:19:55.500 I don't know why you would like it, but okay. 395 00:19:55.600 --> 00:19:56.000 All right. 396 00:19:56.020 --> 00:19:58.880 So this is the way the Earth looked four billion years ago, 397 00:19:58.920 --> 00:20:00.660 when all these leftover rocks were still present. 398 00:20:00.680 --> 00:20:02.480 They were still pummeling all the planets of the solar system. 399 00:20:02.700 --> 00:20:04.060 But this stopped about three... 400 00:20:04.060 --> 00:20:05.240 Those of you who remember the papers, 401 00:20:05.380 --> 00:20:07.740