WEBVTT 1 00:00:00.000 --> 00:00:03.880 This afternoon to Professor Rachel Webster from the University of Melbourne, 2 00:00:04.040 --> 00:00:11.560 Professor of Astrophysics there, has just finished, I believe, serving as Chair of the National Astronomy Committee, 3 00:00:12.480 --> 00:00:14.380 Council, whatever it's called, I can never remember exactly. 4 00:00:17.100 --> 00:00:19.160 Rachel has a long background in this area. 5 00:00:19.240 --> 00:00:23.840 I think the only time I met her previously was probably when I was giving a talk at the University of Melbourne, 6 00:00:23.880 --> 00:00:27.020 I think in 1994, and I think you'd just come back from Rice University, is that right? 7 00:00:27.780 --> 00:00:28.200 Toronto. 8 00:00:28.520 --> 00:00:28.940 Toronto. 9 00:00:30.000 --> 00:00:36.620 She must have been in Toronto because she said Toronto in the way in which the locals do. 10 00:00:37.920 --> 00:00:43.580 Also been very active in promoting the physical sciences for female students, 11 00:00:43.840 --> 00:00:45.360 which I think is a fundamentally important thing, 12 00:00:45.420 --> 00:00:50.100 and actually it's amazing how many female students do get attracted into the sciences by astronomy. 13 00:00:50.940 --> 00:00:52.660 Astronomy is a fantastic thing. 14 00:00:53.580 --> 00:00:56.800 Lots of people very, very interested in it, obvious from the audience here. 15 00:00:57.160 --> 00:00:59.980 And so without further ado, because you want to listen to her, 16 00:01:00.000 --> 00:01:03.520 not to me, I'll hand over to Rachel Webster to talk about new directions in astronomy. 17 00:01:09.460 --> 00:01:12.420 Well, thank you very much indeed, Duncan. 18 00:01:14.000 --> 00:01:20.700 So I'm going to speak today, I'm going to talk a little bit about how I came to be an astronomer. 19 00:01:20.740 --> 00:01:25.540 I'm going to talk a little bit about astronomy and then just make some broader comments about, 20 00:01:25.920 --> 00:01:28.080 well, indeed, women in astronomy and other things. 21 00:01:28.840 --> 00:01:29.940 So for the person... 22 00:01:30.000 --> 00:01:34.320 For the past 30 years, I've had the privilege of working in astrophysics and cosmology, 23 00:01:35.120 --> 00:01:39.780 and my career in this area has been at once a realisation of a passion, 24 00:01:39.860 --> 00:01:41.500 but also perhaps an accident. 25 00:01:41.780 --> 00:01:49.320 In my late teens, I heard that an American cousin of mine had been selected to attend an international school 26 00:01:49.320 --> 00:01:52.440 on inner and outer space at the University of Sydney. 27 00:01:52.880 --> 00:01:57.740 So I wrote to Professor Harry Messel, as you do when you're 16 and don't know any better, 28 00:01:57.860 --> 00:01:59.840 and asked if I could go too. 29 00:02:00.000 --> 00:02:03.840 And that was my first introduction to cosmology. 30 00:02:04.220 --> 00:02:07.580 To say that it blew my mind was an understatement. 31 00:02:08.140 --> 00:02:14.340 So perhaps a decade later, when I was reorganising the office accommodation in the Victorian Public Service, 32 00:02:14.700 --> 00:02:18.320 I realised that I didn't want to reach 40 and end up saying, 33 00:02:18.460 --> 00:02:22.780 oh my God, I always wanted to be a cosmologist and look, I got stuck in the public service. 34 00:02:23.300 --> 00:02:29.780 So I applied to a bunch of UK universities and surprisingly, in retrospect, was accepted to a couple. 35 00:02:30.000 --> 00:02:35.180 But I really wanted to go to Cambridge, having read that there was a really fine cosmologist there. 36 00:02:35.960 --> 00:02:41.120 Martin Rees wrote to me and said he would be interested in having me as a student, 37 00:02:41.200 --> 00:02:43.840 but first of all, I had to establish that I could do physics, 38 00:02:43.980 --> 00:02:46.340 and then Cambridge could consider my application. 39 00:02:47.020 --> 00:02:50.420 So I completed a Masters and gained a place at Cambridge, 40 00:02:50.580 --> 00:02:53.120 and indeed ended up with Martin Rees as my supervisor. 41 00:02:54.140 --> 00:02:57.400 As far as I was concerned, I was following my passion. 42 00:02:57.980 --> 00:02:59.280 But for reasons... 43 00:02:59.280 --> 00:02:59.980 But for reasons... 44 00:03:00.000 --> 00:03:02.100 For reasons that are not completely clear to me now, 45 00:03:02.300 --> 00:03:08.200 I considered that my other colleagues who had reached or had places at Cambridge 46 00:03:08.200 --> 00:03:12.560 by much more normal academic routes had a greater entitlement than I did. 47 00:03:13.380 --> 00:03:17.580 And I actually remember using the term dilettante to describe myself. 48 00:03:17.740 --> 00:03:19.660 I was there to follow a great passion. 49 00:03:20.500 --> 00:03:22.820 But I've got quite a different perspective now. 50 00:03:23.360 --> 00:03:27.600 I see colleagues around me jockeying for positions of prestige, 51 00:03:28.340 --> 00:03:29.520 for honours, 52 00:03:29.520 --> 00:03:32.680 and for any recognition that will increase the metrics 53 00:03:32.680 --> 00:03:35.060 which measure a successful scientific life. 54 00:03:35.620 --> 00:03:38.640 But for me, it's still the passion 55 00:03:38.640 --> 00:03:41.780 to understand a vast universe out there 56 00:03:41.780 --> 00:03:44.460 which is of paramount importance. 57 00:03:45.140 --> 00:03:48.220 So today what I want to do is to discuss two ideas 58 00:03:48.220 --> 00:03:51.380 which now dominate our ideas in cosmology. 59 00:03:51.860 --> 00:03:54.100 Those are what is the nature of the universe, 60 00:03:54.360 --> 00:03:55.560 and what is life. 61 00:03:56.060 --> 00:03:57.520 To answer these questions, 62 00:03:57.640 --> 00:03:59.100 we need to be able to apply... 63 00:03:59.520 --> 00:04:02.860 a scientific method to understand observations of objects 64 00:04:02.860 --> 00:04:05.200 which are on the other side of the universe. 65 00:04:05.860 --> 00:04:09.460 And I'm going to start by talking about the nature of the universe. 66 00:04:10.320 --> 00:04:12.320 For about 50 years, 67 00:04:12.440 --> 00:04:15.640 we've understood the basic stuff that we're made from. 68 00:04:15.860 --> 00:04:17.600 We call these baryons. 69 00:04:17.760 --> 00:04:22.040 And these were initially made in something that we call the Big Bang. 70 00:04:22.640 --> 00:04:25.980 Now, the Big Bang has absolutely nothing to do with an explosion. 71 00:04:26.260 --> 00:04:28.280 It's quite a misnomer in that way. 72 00:04:28.360 --> 00:04:29.500 But simply refers... 73 00:04:29.520 --> 00:04:31.180 to the earliest times in the universe. 74 00:04:31.700 --> 00:04:34.340 At those times, hydrogen and helium, 75 00:04:34.520 --> 00:04:38.660 the first two elements in the periodic table, were made. 76 00:04:38.780 --> 00:04:39.820 And not much else. 77 00:04:40.360 --> 00:04:44.420 And so where did the elements that are so crucial to life come from? 78 00:04:45.200 --> 00:04:49.340 Well, the only place to manufacture those heavier elements 79 00:04:50.320 --> 00:04:53.720 is in the death throes of a very, very massive star, 80 00:04:53.940 --> 00:04:56.000 which in its last few moments 81 00:04:56.000 --> 00:04:59.100 goes through a cycle of collapsing and heating up, 82 00:04:59.520 --> 00:05:01.600 and it ends with a very massive explosion 83 00:05:02.180 --> 00:05:05.540 which actually generates oxygen, iron, carbon, 84 00:05:05.620 --> 00:05:10.480 and all the elements that we know of as constituents for life. 85 00:05:11.000 --> 00:05:15.380 And in that explosion, those elements are spewed out into space, 86 00:05:15.560 --> 00:05:17.720 and they then form the gas clouds 87 00:05:17.720 --> 00:05:20.120 out of which the next generation of stars is made. 88 00:05:20.600 --> 00:05:25.600 So in a very, very real sense, we are made from stardust. 89 00:05:25.760 --> 00:05:28.560 The actual atoms in your bodies and in mine 90 00:05:28.560 --> 00:05:29.500 were manufactured by the Big Bang. 91 00:05:29.500 --> 00:05:31.000 Manufactured in a supernova explosion 92 00:05:31.000 --> 00:05:34.200 which occurred before our solar system was made. 93 00:05:34.560 --> 00:05:36.620 Quite extraordinary if you think about it. 94 00:05:37.000 --> 00:05:39.540 But the magic of the universe doesn't end there. 95 00:05:40.400 --> 00:05:42.760 Astronomers have a very simple technique 96 00:05:42.760 --> 00:05:45.220 to weigh objects on the other side of the universe. 97 00:05:45.700 --> 00:05:48.600 Obviously, it's quite difficult to go out there with a set of scales 98 00:05:48.600 --> 00:05:50.180 and figure out what a galaxy weighs. 99 00:05:50.740 --> 00:05:55.000 But what we do is we assume that the objects that we see 100 00:05:55.000 --> 00:05:56.420 are in equilibrium. 101 00:05:57.000 --> 00:05:59.340 And by equilibrium, we simply mean 102 00:05:59.500 --> 00:06:02.280 that they're going to sit there for quite a long time 103 00:06:02.280 --> 00:06:04.740 and remain in the state that they're in. 104 00:06:05.020 --> 00:06:06.720 It doesn't mean that they're stationary, 105 00:06:06.800 --> 00:06:08.680 but they'll just remain the way they are 106 00:06:08.680 --> 00:06:10.020 for perhaps billions of years. 107 00:06:10.820 --> 00:06:13.960 If we see a concentration of stars or of galaxies 108 00:06:13.960 --> 00:06:16.360 that are remaining constant like this, 109 00:06:16.540 --> 00:06:19.140 then what it tells us is that the gravity 110 00:06:19.140 --> 00:06:20.760 which is holding that object together 111 00:06:20.760 --> 00:06:24.140 must be perfectly balanced by the motions of the objects 112 00:06:24.140 --> 00:06:25.460 wanting to hold it up. 113 00:06:25.560 --> 00:06:27.280 So we have an equilibrium situation. 114 00:06:31.080 --> 00:06:33.760 The motions, of course, would drive the body apart, 115 00:06:33.900 --> 00:06:35.980 and so the gravity holds it together. 116 00:06:36.360 --> 00:06:40.460 Now, we can measure quite readily with our large telescopes, 117 00:06:40.520 --> 00:06:42.260 we can measure the motions of the objects, 118 00:06:42.280 --> 00:06:43.660 whether they're stars or galaxies. 119 00:06:44.060 --> 00:06:46.140 And so what that allows us then to do 120 00:06:46.140 --> 00:06:48.760 is to calculate how much gravity is needed 121 00:06:48.760 --> 00:06:50.020 to hold the object together. 122 00:06:50.740 --> 00:06:55.120 And when we do that, we can work out what the mass of the object is, 123 00:06:55.200 --> 00:06:58.900 because that is just a measure of the gravity. 124 00:06:59.500 --> 00:07:02.620 So when we do this, we discover that there must be 125 00:07:02.620 --> 00:07:06.360 about five times as much matter in these objects 126 00:07:06.360 --> 00:07:08.000 as the matter that we can see. 127 00:07:08.720 --> 00:07:11.900 And the evidence for this additional matter 128 00:07:11.900 --> 00:07:13.960 is really very, very strong now. 129 00:07:14.100 --> 00:07:19.080 It's probably completely without argument, I would say. 130 00:07:19.400 --> 00:07:23.040 And so we've given a name to this matter that we can't see. 131 00:07:23.120 --> 00:07:26.500 We call it dark matter, because we literally can't see it. 132 00:07:26.740 --> 00:07:29.220 So our colleagues, the particle physicists, 133 00:07:29.500 --> 00:07:33.080 are hunting for this stuff in their experiments at CERN 134 00:07:33.080 --> 00:07:34.940 using the Large Hadron Collider. 135 00:07:35.000 --> 00:07:36.960 This is the very big accelerator, 136 00:07:37.020 --> 00:07:41.900 which is under parts of France and Switzerland, near Geneva. 137 00:07:42.160 --> 00:07:45.880 And they accelerate charged particles to very, very high velocities 138 00:07:45.880 --> 00:07:49.620 and crash them together to see if they can in fact form 139 00:07:49.620 --> 00:07:54.480 these dark matter particles that we know must exist. 140 00:07:55.100 --> 00:07:57.620 The theoreticians have quite a few ideas 141 00:07:57.620 --> 00:07:59.480 of where these particles might fit in. 142 00:07:59.500 --> 00:08:01.360 To their models for the structure of matter. 143 00:08:01.540 --> 00:08:05.380 But as yet, nobody has actually detected one of these dark matter particles. 144 00:08:05.680 --> 00:08:08.220 So we don't actually have a name, if you like, 145 00:08:08.380 --> 00:08:12.500 or a proper definition of exactly what this dark matter is. 146 00:08:12.660 --> 00:08:15.380 But astronomers have been able to tell the physicists 147 00:08:15.380 --> 00:08:17.000 that it definitely exists. 148 00:08:18.000 --> 00:08:21.660 This story has really only solidified in the last 15 years or so. 149 00:08:21.960 --> 00:08:24.080 And it seems strange enough. 150 00:08:24.440 --> 00:08:28.100 But it's actually not the end of the strange story of cosmology 151 00:08:28.100 --> 00:08:29.300 as we understand it today. 152 00:08:29.300 --> 00:08:32.840 Our understanding of the universe has recently taken 153 00:08:32.840 --> 00:08:35.020 a new and totally unexpected direction. 154 00:08:36.960 --> 00:08:39.060 There's another constituent in the universe. 155 00:08:39.360 --> 00:08:43.220 And this one is not like baryonic matter, which we know and love, 156 00:08:43.360 --> 00:08:45.920 or dark matter, which has at least been around for a while 157 00:08:45.920 --> 00:08:47.680 and we think we can describe. 158 00:08:48.280 --> 00:08:51.160 Both of these sorts of matter behave quite reasonably, 159 00:08:51.360 --> 00:08:54.580 and they have mass, and they gravitationally attract. 160 00:08:54.860 --> 00:08:57.720 So we can describe their behaviour in a quite straightforward way. 161 00:08:59.300 --> 00:09:00.660 But this stuff behaves very differently. 162 00:09:01.300 --> 00:09:06.800 It actually acts to cause the universe to expand on the very larger scales. 163 00:09:07.200 --> 00:09:10.820 It acts in the opposite way to gravity. 164 00:09:11.880 --> 00:09:14.820 We're used to the idea that the universe is expanding, 165 00:09:15.040 --> 00:09:17.760 although I think this is quite a challenging idea 166 00:09:17.760 --> 00:09:21.740 for somebody who hasn't necessarily worked in cosmology for a while. 167 00:09:21.880 --> 00:09:24.540 But as a cosmologist, you get quite used to the idea 168 00:09:24.540 --> 00:09:26.240 that the universe is actually expanding. 169 00:09:26.700 --> 00:09:28.080 But until now, 170 00:09:29.300 --> 00:09:32.220 we've believed that that expansion has been slowing down with time 171 00:09:32.220 --> 00:09:35.800 as the gravitational force of the matter in the universe 172 00:09:35.800 --> 00:09:38.680 actually acts to cause a deceleration. 173 00:09:39.120 --> 00:09:42.060 So we've got an expanding universe, but it's actually slowing down. 174 00:09:42.380 --> 00:09:43.980 And the question has always been 175 00:09:43.980 --> 00:09:45.940 whether or not it would slow down enough 176 00:09:45.940 --> 00:09:48.200 to stop and turn around and collapse again, 177 00:09:48.380 --> 00:09:50.800 or whether the expansion was stronger 178 00:09:50.800 --> 00:09:52.620 and it would in fact expand forever. 179 00:09:53.180 --> 00:09:57.540 It turns out that both of those scenarios are quite wrong. 180 00:09:57.540 --> 00:10:00.440 The universe isn't going to do either of those things 181 00:10:00.440 --> 00:10:03.360 because there's this new component in the universe, 182 00:10:03.460 --> 00:10:04.220 this new stuff, 183 00:10:04.480 --> 00:10:07.460 which is actually increasing the rate of expansion. 184 00:10:07.780 --> 00:10:09.860 So it's expanding and then it's increasing, 185 00:10:10.040 --> 00:10:12.320 and that rate of expansion is actually accelerating. 186 00:10:12.920 --> 00:10:15.360 So we do know what sort of universe we live in. 187 00:10:15.420 --> 00:10:17.320 It's one where the expansion is accelerating. 188 00:10:17.840 --> 00:10:22.260 It's driven by stuff that is really quite foreign to us 189 00:10:22.260 --> 00:10:24.760 in any way that we've understood up until now. 190 00:10:25.120 --> 00:10:26.620 We've coined a term, of course, 191 00:10:26.620 --> 00:10:27.600 to describe this stuff. 192 00:10:27.680 --> 00:10:28.640 It's called dark energy. 193 00:10:29.680 --> 00:10:33.420 But to say that we have much deeper understanding than that 194 00:10:33.420 --> 00:10:36.820 would be stretching a point, I think. 195 00:10:39.120 --> 00:10:41.560 So we can write down a few simple equations 196 00:10:41.560 --> 00:10:43.120 to describe the dark energy, 197 00:10:43.280 --> 00:10:46.900 but at this stage, as I say, 198 00:10:46.940 --> 00:10:49.400 we understand very little else about it. 199 00:10:50.280 --> 00:10:53.880 So I think it should come as no surprise 200 00:10:54.620 --> 00:10:56.600 that the universe still has major, 201 00:10:56.620 --> 00:10:58.140 new challenges to offer us. 202 00:10:58.560 --> 00:11:00.040 As physical scientists, 203 00:11:00.180 --> 00:11:03.380 we've concentrated on trying to describe the physical universe, 204 00:11:03.680 --> 00:11:07.620 even suggesting that we might be able to develop 205 00:11:07.620 --> 00:11:08.780 a theory of everything. 206 00:11:09.780 --> 00:11:12.500 Yet we've completely ignored the fact 207 00:11:12.500 --> 00:11:16.640 that life, intelligence, consciousness, and so on, 208 00:11:16.660 --> 00:11:18.400 all must exist in our universe 209 00:11:18.400 --> 00:11:20.740 and must, in some sense, 210 00:11:20.880 --> 00:11:23.260 be a consequence of the nature and structure 211 00:11:23.260 --> 00:11:24.720 of the universe that we live in. 212 00:11:25.440 --> 00:11:27.540 This last decade has seen the development 213 00:11:27.540 --> 00:11:30.060 of a major new area called astrobiology, 214 00:11:30.720 --> 00:11:33.040 or the search for life amongst the stars. 215 00:11:33.600 --> 00:11:35.160 It's still in its infancy, 216 00:11:35.300 --> 00:11:38.720 however the roadmap for this search is starting to bear fruit. 217 00:11:39.220 --> 00:11:41.600 We are starting to ask the right questions 218 00:11:41.600 --> 00:11:43.240 and even to answer some of them. 219 00:11:44.260 --> 00:11:49.580 We found our first planet outside our solar system in 1995, 220 00:11:49.960 --> 00:11:51.880 so that's just 14 years ago, 221 00:11:52.060 --> 00:11:53.360 and at last count, 222 00:11:53.360 --> 00:11:57.960 we knew of over 350 planets outside our solar system. 223 00:11:58.120 --> 00:12:01.460 They're coming in at the moment at the rate of a few a week, 224 00:12:01.600 --> 00:12:02.780 so quite rapidly. 225 00:12:03.460 --> 00:12:05.200 Most of the planets we're finding 226 00:12:05.200 --> 00:12:08.800 are quite in solar systems that are quite different from our own. 227 00:12:08.960 --> 00:12:12.160 So this has been our first surprise, if you like. 228 00:12:12.640 --> 00:12:16.180 But that may still just be what we call a selection effect. 229 00:12:16.240 --> 00:12:19.260 It may just be a result of the sort of observations 230 00:12:19.260 --> 00:12:21.580 that we've been able to make up until now. 231 00:12:21.940 --> 00:12:23.340 What we're finding a lot, 232 00:12:23.340 --> 00:12:25.080 are lots of planets like Jupiter, 233 00:12:25.220 --> 00:12:26.500 lots of Jupiter-like planets, 234 00:12:27.500 --> 00:12:30.300 but the thing that has been surprising 235 00:12:30.300 --> 00:12:33.940 is that a lot of them are sitting closer to their star than Mercury. 236 00:12:34.280 --> 00:12:36.980 Okay, so really, really quite close in. 237 00:12:37.060 --> 00:12:38.420 We call these hot Jupiters. 238 00:12:39.400 --> 00:12:42.320 We found a few planets with masses as low as Earth, 239 00:12:42.480 --> 00:12:45.020 but those planets are quite difficult to detect 240 00:12:45.020 --> 00:12:48.800 and our techniques for doing that are just starting to bear fruit. 241 00:12:49.960 --> 00:12:52.720 And what we're now starting to do is to look for planets, 242 00:12:52.720 --> 00:12:54.160 which might have liquid water. 243 00:12:54.500 --> 00:12:58.040 Because generally, we expect that if you want to find life, 244 00:12:58.260 --> 00:13:04.280 then liquid water or something that operates in a very similar way to liquid water 245 00:13:04.280 --> 00:13:08.620 will be necessary to protect life in its early stages of evolution. 246 00:13:09.720 --> 00:13:11.860 So astronomers are working with biologists 247 00:13:11.860 --> 00:13:15.800 to understand what might constitute a signature for life 248 00:13:15.800 --> 00:13:18.760 as we look at a planet, not halfway across the universe, 249 00:13:18.840 --> 00:13:21.140 but somewhere out there in our galaxy. 250 00:13:21.140 --> 00:13:25.000 And in that process, of course, 251 00:13:25.140 --> 00:13:27.400 we're also starting, along with the biologists 252 00:13:27.400 --> 00:13:28.900 who have been doing this for much longer, 253 00:13:29.020 --> 00:13:32.220 to think about what constitutes a definition of life. 254 00:13:32.400 --> 00:13:36.960 What is life and what would we expect to detect? 255 00:13:37.920 --> 00:13:42.440 I believe that finding life somewhere other than on Earth 256 00:13:42.440 --> 00:13:45.340 would constitute a radical shift in our understanding 257 00:13:45.340 --> 00:13:47.080 of who we are in the universe, 258 00:13:47.280 --> 00:13:49.520 comparable to the shift in understanding 259 00:13:50.360 --> 00:13:51.120 developed by the universe. 260 00:13:51.140 --> 00:13:54.160 And that's what, when Copernicus described the solar system, 261 00:13:54.300 --> 00:13:57.400 a solar system where Earth was not at the centre of our universe, 262 00:13:57.620 --> 00:14:02.200 but simply one of a number of planets orbiting around a very ordinary star, 263 00:14:02.420 --> 00:14:03.100 our Sun. 264 00:14:04.160 --> 00:14:06.840 So, finally, what I would like to comment on 265 00:14:06.840 --> 00:14:11.020 is what it means to be a woman in astronomy. 266 00:14:11.780 --> 00:14:13.500 How do women do science, 267 00:14:13.700 --> 00:14:16.980 and how do they fare as members of the scientific community? 268 00:14:17.980 --> 00:14:20.600 The following comments reflect the things 269 00:14:21.140 --> 00:14:21.880 that have been observed and understood 270 00:14:21.880 --> 00:14:25.900 over the past 30 years or so working as an astronomer. 271 00:14:26.300 --> 00:14:30.560 Astronomy is perhaps one of the softest of the hard sciences 272 00:14:31.140 --> 00:14:34.340 and has allowed for some collective introspection 273 00:14:35.140 --> 00:14:36.700 from a group of active women researchers 274 00:14:36.700 --> 00:14:38.940 who have risen through the ranks internationally. 275 00:14:39.660 --> 00:14:43.840 So the following comments reflect not only experience in astronomy, 276 00:14:44.000 --> 00:14:45.780 but probably more broadly as well, I think. 277 00:14:46.100 --> 00:14:48.720 So the first thing that I want to comment on 278 00:14:48.720 --> 00:14:50.880 is that I think women see, 279 00:14:50.880 --> 00:14:54.160 a more complex web or network, 280 00:14:54.380 --> 00:14:57.960 not only in the prosecution of their scientific endeavours, 281 00:14:58.000 --> 00:15:00.100 but also in their personal relationships 282 00:15:00.100 --> 00:15:03.220 with the others who are undertaking study with them. 283 00:15:03.460 --> 00:15:05.720 For the most part, they don't work in isolation, 284 00:15:05.840 --> 00:15:08.460 but strive to be part of a community of scholars. 285 00:15:09.620 --> 00:15:13.320 The second comment I would make is that in science, 286 00:15:13.480 --> 00:15:14.960 if you're broadly focused, 287 00:15:15.300 --> 00:15:18.800 it's much harder to scale extraordinary heights 288 00:15:18.800 --> 00:15:20.200 in some narrow area. 289 00:15:20.200 --> 00:15:22.200 It's a very competitive arena, 290 00:15:22.240 --> 00:15:26.560 and the accolades go to those who can push to the greatest heights, 291 00:15:26.800 --> 00:15:29.780 spend the longest hours, travel at the drop of a hat, 292 00:15:30.040 --> 00:15:33.700 move to a new position every few years, and so on. 293 00:15:33.980 --> 00:15:36.680 There are actually few women amongst us 294 00:15:36.680 --> 00:15:40.920 who are prepared to forego the joys of family life, 295 00:15:41.080 --> 00:15:43.080 support of a community, 296 00:15:43.260 --> 00:15:46.360 and the more holistic lifestyle 297 00:15:46.360 --> 00:15:48.600 simply to pursue a scientific career. 298 00:15:49.500 --> 00:15:50.180 So, 299 00:15:50.200 --> 00:15:52.860 the third point is that I think women are certainly 300 00:15:52.860 --> 00:15:57.480 no less intellectually able than their male counterparts. 301 00:15:57.920 --> 00:15:59.960 But perhaps they may have more choices 302 00:15:59.960 --> 00:16:01.660 from being more broadly talented. 303 00:16:02.740 --> 00:16:06.200 Provocatively, I'll say that there is now some evidence 304 00:16:06.200 --> 00:16:09.340 that women who are rather good at maths and science 305 00:16:09.340 --> 00:16:11.240 often excel in the humanities as well, 306 00:16:11.380 --> 00:16:14.840 and that, of course, offers them a broader choice of career. 307 00:16:15.560 --> 00:16:19.480 So, in summary, I would say that the proclivities and choices of women 308 00:16:19.480 --> 00:16:23.580 have mitigated against them making science a career. 309 00:16:24.100 --> 00:16:25.860 Of course, there are additional issues, 310 00:16:25.920 --> 00:16:27.480 such as the absence of mentoring, etc., 311 00:16:28.220 --> 00:16:30.220 which can affect a woman's career. 312 00:16:31.100 --> 00:16:34.640 But I think those broad issues that I mentioned first 313 00:16:34.640 --> 00:16:36.720 are probably the dominant ones. 314 00:16:38.000 --> 00:16:43.340 So, let me sort of draw the comments that I wanted to make 315 00:16:43.340 --> 00:16:45.760 to a conclusion. 316 00:16:46.500 --> 00:16:49.060 Science has taught us how to understand the stars. 317 00:16:49.060 --> 00:16:52.400 But the universe is actually turning out to be 318 00:16:52.400 --> 00:16:55.920 a much more complex and interesting place than we expected. 319 00:16:56.380 --> 00:17:00.100 It is unclear that our journey to understand it has an end point. 320 00:17:00.340 --> 00:17:04.220 It may, in fact, be a journey without an end point. 321 00:17:04.780 --> 00:17:08.820 And the practice of scientific endeavour 322 00:17:08.820 --> 00:17:13.520 has been quite gendered, I think, over the last century or so. 323 00:17:15.060 --> 00:17:18.700 And indeed, the last few comments I want to make 324 00:17:18.700 --> 00:17:19.040 are about the importance of science. 325 00:17:19.060 --> 00:17:21.840 They are about our broader management of our planet, 326 00:17:22.020 --> 00:17:26.200 which is, after all, just a small and rather insignificant part of the universe. 327 00:17:26.600 --> 00:17:29.020 And I believe our management of our planet 328 00:17:29.020 --> 00:17:31.440 has actually been... 329 00:17:32.060 --> 00:17:35.560 ..has left us in a rather untenable and unsustainable position. 330 00:17:36.180 --> 00:17:40.600 This is something that we would now term climate change. 331 00:17:40.880 --> 00:17:43.460 And what we need is a much more holistic approach 332 00:17:43.460 --> 00:17:47.720 not only to our science, but to its role in the wider community. 333 00:17:47.720 --> 00:17:50.400 We have the opportunity to take lessons 334 00:17:50.400 --> 00:17:52.540 from understanding the stars and the planets, 335 00:17:53.840 --> 00:17:56.780 understanding what happens in the atmospheres of planets 336 00:17:56.780 --> 00:17:58.220 in our own solar system, 337 00:17:58.300 --> 00:18:00.320 and apply that to our own backyard. 338 00:18:00.780 --> 00:18:02.660 And I believe that climate change 339 00:18:02.660 --> 00:18:05.340 is going to force us to reconsider how we live. 340 00:18:06.840 --> 00:18:10.840 The outcome cannot be a scientifically-based society 341 00:18:10.840 --> 00:18:13.400 which exploits its physical and human resources 342 00:18:13.400 --> 00:18:15.740 to provide great material comfort for a few. 343 00:18:16.160 --> 00:18:17.700 Rather, we need to develop a system 344 00:18:17.700 --> 00:18:18.260 to develop a society 345 00:18:18.260 --> 00:18:21.200 which will provide a comfortable existence for all, 346 00:18:21.320 --> 00:18:24.560 and as a bonus, free all of us to explore 347 00:18:24.560 --> 00:18:28.120 intellectual, artistic, emotional, philosophical 348 00:18:28.700 --> 00:18:31.260 and other what I call energy-free pursuits 349 00:18:31.260 --> 00:18:36.020 which can only enhance our collective and individual wellbeing. 350 00:18:36.600 --> 00:18:37.620 OK, thank you. 351 00:18:46.900 --> 00:18:48.600 Thank you very much, Rachel. 352 00:18:48.620 --> 00:18:49.800 We've got plenty of time for questions, 353 00:18:49.860 --> 00:18:50.580 which is a great thing, 354 00:18:50.580 --> 00:18:51.960 usually we have a shorter time for questions. 355 00:18:52.100 --> 00:18:53.440 Now, there's a roving mic over here 356 00:18:53.440 --> 00:18:57.880 which I'd like to just give the lady a chance to get to you 357 00:18:57.880 --> 00:18:59.280 so everybody else can hear your question. 358 00:18:59.720 --> 00:19:00.280 Please, sir. 359 00:19:00.700 --> 00:19:01.340 Two questions. 360 00:19:01.480 --> 00:19:02.480 Firstly, a technical one. 361 00:19:03.000 --> 00:19:05.560 The Earth, as I understand it, is mainly iron and nickel, 362 00:19:05.700 --> 00:19:06.700 a big lump, 363 00:19:06.700 --> 00:19:09.060 and the oxygen and water and all that sort of stuff 364 00:19:09.060 --> 00:19:10.220 is part of the cloud, 365 00:19:10.300 --> 00:19:12.640 the dust that is collected from the stars. 366 00:19:13.460 --> 00:19:17.540 Did the Earth pop out of one of these explosions as a whole lump? 367 00:19:17.920 --> 00:19:20.800 And then all the other bits that got on it come later? 368 00:19:21.500 --> 00:19:22.480 That's the first question. 369 00:19:22.500 --> 00:19:25.040 And the second question is more on the career aspect 370 00:19:25.040 --> 00:19:26.000 that you were talking about. 371 00:19:29.000 --> 00:19:32.880 Is or does modern technology allow you 372 00:19:32.880 --> 00:19:35.780 to get out of this geographical trap you seem to be in 373 00:19:35.780 --> 00:19:36.160 about... 374 00:19:36.700 --> 00:19:37.220 having to... 375 00:19:37.220 --> 00:19:37.980 What have you got to chase? 376 00:19:38.100 --> 00:19:40.900 The radio telescopes or something in your career? 377 00:19:41.360 --> 00:19:41.880 OK. 378 00:19:42.280 --> 00:19:45.400 Let me answer the first question 379 00:19:45.400 --> 00:19:47.660 about the formation of the solar system first of all. 380 00:19:47.860 --> 00:19:53.460 So the idea we have for the evolution of the solar system 381 00:19:53.460 --> 00:19:57.020 is that we start with just a gas cloud, 382 00:19:58.800 --> 00:20:00.980 which wouldn't necessarily be very dense, 383 00:20:01.040 --> 00:20:01.920 might be quite large, 384 00:20:02.700 --> 00:20:05.380 and then it starts to collapse under gravity, 385 00:20:05.380 --> 00:20:06.480 so it contracts. 386 00:20:06.800 --> 00:20:09.200 It might have a little bit of rotation initially, 387 00:20:09.360 --> 00:20:11.320 but of course just like an ice skater, 388 00:20:11.340 --> 00:20:16.180 as it contracts it spins up until it's rotating quite quickly. 389 00:20:17.940 --> 00:20:21.000 The stuff at the centre condenses to form the sun, 390 00:20:21.120 --> 00:20:23.400 and around the sun is a disk of material 391 00:20:23.400 --> 00:20:26.160 which still has that... 392 00:20:26.160 --> 00:20:27.820 what we call... 393 00:20:27.820 --> 00:20:31.460 would still have the same concentration of elements as the sun. 394 00:20:31.580 --> 00:20:32.960 So it would still be, you know, 395 00:20:32.980 --> 00:20:33.560 90... 396 00:20:34.360 --> 00:20:35.560 99% hydrogen, 397 00:20:36.320 --> 00:20:37.200 you know, a bit of helium, 398 00:20:37.340 --> 00:20:39.400 and a few of the heavier elements. 399 00:20:40.020 --> 00:20:43.200 Then as time progresses in that disk, 400 00:20:44.420 --> 00:20:47.380 little bits of dust and stuff start sticking together, 401 00:20:47.440 --> 00:20:49.720