1 00:00:01,220 --> 00:00:27,060 So while. So welcome all of you to Oxford Physics from all of us in the Oxford Physics family, which numbers more than 1500 of us in Oxford. 2 00:00:28,080 --> 00:00:35,159 And this welcome is extended not just to all of you in the Merchant Wood Lecture Theatre here, but also in the adjacent lecture theatre. 3 00:00:35,160 --> 00:00:40,380 The Lindemann and many people that are joining us around the world live through streaming now. 4 00:00:42,000 --> 00:00:46,980 My name is in Chips and I've been head of Oxford Physics for the last 22 or so days. 5 00:00:49,200 --> 00:00:54,030 There's less. Makes me an incredible extra nice. So this is why I'm writing the notes. 6 00:00:55,080 --> 00:01:05,550 So, as you know, physics provides the basis for much of modern society from the microelectronics that enable us laptops and computers 7 00:01:05,970 --> 00:01:14,100 to the vast array of advanced instrumentation that we find in hospitals that speeds diagnosis and facilitates cure. 8 00:01:15,240 --> 00:01:21,960 It's about a thousand students studying physics in Oxford at the moment, and they're pretty talented group, rather proud of them. 9 00:01:22,590 --> 00:01:28,020 Three of them, Martin Rowe, Tony Leggett and Joe Michael Cosmos went on to win the Nobel Prize, 10 00:01:28,620 --> 00:01:31,950 and others have had a truly immense impact on our world. 11 00:01:31,980 --> 00:01:38,130 For example, Tim Berners-Lee invented the World Wide Web and the brilliant inspiration of Stephen Hawking. 12 00:01:39,360 --> 00:01:45,929 Physics works best when theorists and experimentalists work side by side to measure what 13 00:01:45,930 --> 00:01:51,690 is measurable and make measurable what is not so and to interpret those measurements. 14 00:01:52,200 --> 00:02:01,170 We do all of those things at Oxford to learn more about a marvellous cosmos on all scales, from the subatomic to the entire universe. 15 00:02:02,360 --> 00:02:09,170 Tonight's lecture is the beginning of a new partnership with the Worshipful Company of Scientific Instrument Makers. 16 00:02:09,950 --> 00:02:13,700 To tell you about the company and a little about what they're going to be doing together. 17 00:02:14,150 --> 00:02:20,540 Please welcome the personnel of the company, John. Thank you. 18 00:02:25,450 --> 00:02:28,990 Good evening. I did have some notes here, but they've disappeared. 19 00:02:30,010 --> 00:02:42,970 Fortunately, being a Boy Scout, I. I bought a spare set, so I was asked to keep it brief. 20 00:02:42,980 --> 00:02:48,410 So in six sentences I'm going to sell who we are, what we do, and why we are here. 21 00:02:50,330 --> 00:02:53,480 Peculiar to the first of all, we are. 22 00:02:56,850 --> 00:03:02,580 First of all, we are a trade guilds and peculiar to the City of London. 23 00:03:02,700 --> 00:03:13,620 We are also known as a livery company. There are 130 such livery companies in the City of London, each representing a trade profession or an industry. 24 00:03:15,510 --> 00:03:22,469 And they support. And some of the old deliverers can actually trace themselves back to the 12th century. 25 00:03:22,470 --> 00:03:26,010 So there is quite a bit of history involved as well. 26 00:03:27,210 --> 00:03:31,760 We have three main roles. One is to promote the industry that we represent. 27 00:03:31,770 --> 00:03:37,680 So in our case, scientific instruments to support the ancient traditions of the City of London. 28 00:03:37,860 --> 00:03:41,460 You know, the Lord Mayor, the sheriffs, the aldermen and so on. 29 00:03:42,450 --> 00:03:51,150 But perhaps the most important role that we have is to nurture our younger members who have shown interest in scientific instruments. 30 00:03:52,860 --> 00:03:55,250 We have to feed subjects for our industry. 31 00:03:55,260 --> 00:04:02,880 They are physics and precision engineering, and we try to keep abreast of the developments of both subjects. 32 00:04:03,690 --> 00:04:07,860 Hence, our relationship with the physics department here in Oxford. 33 00:04:10,050 --> 00:04:18,270 As Ian said, this evening is the beginning of a new partnership between our West Company and the physics department here that 34 00:04:18,270 --> 00:04:25,920 will involve potential sponsorship and the holding of more joint events such as this this evening's lecture. 35 00:04:26,850 --> 00:04:35,399 So you can watch out for those. Membership of our organisation is open to anybody who has an interest in scientific 36 00:04:35,400 --> 00:04:41,940 instruments and there'll be more information available in the drinks reception afterwards. 37 00:04:43,200 --> 00:04:48,090 So there we are. That's my six sentences and I'm now handed over to Ben, who will get things rolling. 38 00:04:48,600 --> 00:04:58,179 Thank you very much. One of Oxford's greatest strengths is its students. 39 00:04:58,180 --> 00:05:03,459 And so it's a great pleasure to introduce one of our students and astrophysicist Ben Fernando to introduce the speaker tonight. 40 00:05:03,460 --> 00:05:11,150 Please welcome back. Thank you, everyone, for attending. 41 00:05:11,420 --> 00:05:14,330 Whether you're in this room or in one of the overflow rooms or watching online, 42 00:05:14,720 --> 00:05:20,150 we're delighted this afternoon to welcome Dr. Jim Green, currently the chief scientist at NASA. 43 00:05:20,780 --> 00:05:28,730 I had a substantial biography prepared to tell you all about the missions he's been involved in within our solar system and what he's working on now, 44 00:05:28,940 --> 00:05:32,120 including the time he spent as director of NASA's Planetary Science Division. 45 00:05:32,870 --> 00:05:37,760 However, he told me to keep the biography to two sentences. I think I've already gone over that. 46 00:05:37,970 --> 00:05:43,940 So without further ado, I'd like to ask you to join me in welcoming Dr. Jim Green, chief scientist of NASA. 47 00:05:53,130 --> 00:05:57,090 Thank you very much. It's just a pleasure to be here in Oxford. 48 00:05:57,870 --> 00:06:07,229 And with me, I brought all the Nassar secret files and we are going to open them up and we are going to look 49 00:06:07,230 --> 00:06:14,790 inside and we are going to talk about where we really are in the search for life beyond earth. 50 00:06:16,560 --> 00:06:25,950 And we've made enormous progress. So to begin, I must first tell you what the definition of life is. 51 00:06:26,310 --> 00:06:28,500 All right. We'll start with fundamentals. 52 00:06:29,310 --> 00:06:37,680 And about 15 years ago, we asked our astrobiology group that we just put together give us a definition of life. 53 00:06:38,670 --> 00:06:43,560 They struggled after a couple of years, a couple of conferences, debates. 54 00:06:44,070 --> 00:06:48,660 You know, they came back and they were so proud they'd actually distilled it. 55 00:06:49,500 --> 00:06:53,700 And the reason why I want to know that is I want to be able to build instruments and go out, measure it. 56 00:06:54,210 --> 00:06:57,960 Okay. And I said, okay, what's the definition of life? 57 00:06:58,560 --> 00:07:08,030 And they said, Life has three attributes. It metabolises reproduce as it evolves. 58 00:07:09,300 --> 00:07:19,170 They were delighted. And I can't tell you how sad I was because I don't know how to build an instrument to make those measurements. 59 00:07:20,130 --> 00:07:27,480 So then I stepped back and we said, okay, let's grab the metabolism part of it. 60 00:07:28,230 --> 00:07:31,910 What do we need for metabolism? You have to have the energy source. 61 00:07:31,920 --> 00:07:36,030 You have to have the organics. You have to be able. 62 00:07:37,320 --> 00:07:45,330 When you ingest food with water still to be a solvent and then and then eliminate waste. 63 00:07:46,400 --> 00:07:50,660 So then there are three ingredients that we could actually make measurements of. 64 00:07:50,930 --> 00:07:54,799 Okay, so now we're getting to know an area where we can do some things, 65 00:07:54,800 --> 00:08:00,740 the ingredients of life and then, oh, by the way, there's this pesky thing called time. 66 00:08:00,950 --> 00:08:07,310 Okay. You may have all the right ingredients that would form a habitable environment. 67 00:08:08,560 --> 00:08:14,310 But you have to have time to be able to have that spark, whatever that is. 68 00:08:14,320 --> 00:08:21,130 And we don't know what that is. We don't know what it's taken to have to go from the right environment to have life. 69 00:08:21,790 --> 00:08:29,410 Okay. But if we can go out into the solar system and look for those things, we'll actually have a chance. 70 00:08:29,920 --> 00:08:36,190 But before we do that, I asked the astrobiologist, go to extremes on this earth, 71 00:08:36,670 --> 00:08:45,430 go to the driest deserts, go to places where, you know, the the acidity is huge. 72 00:08:46,360 --> 00:08:52,960 Or go to nuclear plants where the waste materials there and look for life. 73 00:08:53,200 --> 00:08:56,830 Tell me if there's life in those regions. And they did. 74 00:08:57,130 --> 00:09:03,480 And it's all over the place. And the fundamental thing about it is where there's water, there's life. 75 00:09:04,020 --> 00:09:08,920 Now, they also went into deep mines. Two miles below the earth. 76 00:09:10,100 --> 00:09:14,820 And where there was water, there was life. And so we now know. 77 00:09:15,890 --> 00:09:19,740 Much about our biosphere. There's more. 78 00:09:21,000 --> 00:09:25,050 Biology below our feet in mass. 79 00:09:25,170 --> 00:09:32,460 More biomass of life below our feet than is on the surface of this planet. 80 00:09:33,030 --> 00:09:37,200 And so during times of extreme life moves into the rocks. 81 00:09:37,840 --> 00:09:41,200 Okay. So those are really great attributes. 82 00:09:41,220 --> 00:09:45,210 Those are things that we can go after because we see extremes in space. 83 00:09:46,380 --> 00:09:51,030 Okay. But there's another dimension. We live on this planet. 84 00:09:51,540 --> 00:09:55,860 This planet is 4.6 billion years old. 85 00:09:56,940 --> 00:09:59,970 And it hasn't always had life. All right. 86 00:10:00,540 --> 00:10:04,260 It's gone through enormous changes. There's been five mass extinctions. 87 00:10:05,360 --> 00:10:08,990 We need to also look at this time dimension. Okay. 88 00:10:09,410 --> 00:10:13,670 And to look at the time dimension we really need to look at. 89 00:10:14,780 --> 00:10:18,740 How bright our sun is and what is our sun doing? 90 00:10:18,800 --> 00:10:27,790 What is the evolution of our star? So since the sun came together 4.6 billion years ago. 91 00:10:29,370 --> 00:10:40,570 It has brightened. In fact, we believe the luminosity may be as much as 25 to 30% less back then than it is today. 92 00:10:42,290 --> 00:10:52,940 And so from an astronomer perspective, looking at stars and looking at the heat from the stars, they have defined a region around a star. 93 00:10:53,870 --> 00:10:58,340 Where the temperature is such that if you had an Earth sized planet. 94 00:10:59,300 --> 00:11:11,210 With water. One could expect in this green area, this habitable zone area, water to exist in three phases liquid solid vapour. 95 00:11:11,930 --> 00:11:14,720 They defined that as the habitable zone. 96 00:11:15,260 --> 00:11:27,140 That was the first step in taking a look at where exoplanets are being found today, where there might be a possibility of life. 97 00:11:28,250 --> 00:11:33,500 I wish it was that simple and I think you'll see how difficult it's gotten. 98 00:11:33,500 --> 00:11:37,670 But I think we're also making a lot of a lot of progress in this concept. 99 00:11:37,670 --> 00:11:42,020 But this was the first initial concept, a really good start to doing that. 100 00:11:42,800 --> 00:11:49,610 So then when we look at our sun as it is, increased intensity over time, that habitable zone that has moved out. 101 00:11:51,140 --> 00:11:55,400 So when we look at Mars and we look at Venus and we look at its past. 102 00:11:56,430 --> 00:11:58,770 And when it was in the habitable zone. 103 00:12:00,490 --> 00:12:09,610 Where the conditions were such that that light from the sun could produce an environment where water could exist in those phases, 104 00:12:09,850 --> 00:12:21,610 and therefore life could have company that one sees then that it's only in the future where that habitable zone will eventually reach Mars. 105 00:12:21,860 --> 00:12:25,690 Okay, so maybe we shouldn't have looked at Mars for life. 106 00:12:26,560 --> 00:12:35,650 And that's one of the fallacies of this concept. We have to be smarter than just use the concept of a habitable zone to look at it. 107 00:12:36,010 --> 00:12:45,400 All right. So let's go through our solar system, not only in the space starting from mercury, but in time. 108 00:12:45,790 --> 00:12:55,750 In time. And and compare what we're finding out with what this picture tells us of how the habitable zone moves outward. 109 00:12:56,920 --> 00:13:02,110 There's also another line in this area. It's called the snow line. 110 00:13:02,290 --> 00:13:05,979 Okay. And to visualise what the snow line is. 111 00:13:05,980 --> 00:13:12,640 Let's say you had an ice cube out at Pluto and you move the ice cube closer and closer to the sun. 112 00:13:13,030 --> 00:13:22,270 And finally you got to the point where the lattice couldn't hold it together and the molecules were popping off, and that's called sublimation. 113 00:13:22,690 --> 00:13:26,679 And you go from solid to vapour. That's the snow line. 114 00:13:26,680 --> 00:13:35,050 Well, actually, it's a sphere around the sun. And that snow line today exists out in the asteroid belt. 115 00:13:36,850 --> 00:13:42,820 And so from a planetary scientist perspective, when we approach these things at least ten years ago, 116 00:13:43,090 --> 00:13:49,479 the concept is, well, if there's water in the outer part of our solar system, it's going to be ice. 117 00:13:49,480 --> 00:13:56,260 It's going to be solid. Okay. Well, that's a real downer because we need some liquid water to be able to do this metabolism thing. 118 00:13:57,160 --> 00:14:01,560 And so we're going to have to watch what happens with that, too. All right. 119 00:14:01,800 --> 00:14:06,330 Mercury and mercury, indeed, is our our our first planet. 120 00:14:06,640 --> 00:14:12,540 It's larger than the moon, but it's not a large planet. 121 00:14:12,810 --> 00:14:16,830 It has its own magnetic field. It's nearly tidally locked. 122 00:14:17,770 --> 00:14:29,740 And it's incredibly hot it out gases and from messenger data we believe we can determine that mercury really didn't have any substantial atmosphere. 123 00:14:30,800 --> 00:14:36,660 And therefore the probability of having life or liquid water on it is very low. 124 00:14:36,680 --> 00:14:41,420 So. So Mercury probably never had a chance at being habitable. 125 00:14:41,990 --> 00:14:45,440 We look at the next planet. What is Venus like today? 126 00:14:45,470 --> 00:14:49,100 Well, Venus is our sister planet. 127 00:14:49,130 --> 00:15:01,550 It's as large as the earth. But indeed, the Russian Soviet Union landing on the venerable missions, looking at the atmosphere and the temperature. 128 00:15:02,420 --> 00:15:05,570 It's really hot. It's an extreme. 129 00:15:05,780 --> 00:15:10,640 Okay. It's where the surface is hot enough to melt lead. 130 00:15:10,970 --> 00:15:14,930 And the pressure on the surface is 90 times our atmospheric pressure. 131 00:15:15,350 --> 00:15:19,640 You have to go deep into the ocean to get 90 atmospheres. 132 00:15:20,540 --> 00:15:26,840 You know, the bathyscaphe could probably barely be able to survive it if we landed it on Venus. 133 00:15:27,530 --> 00:15:30,260 All right. So this is a really tough planet. 134 00:15:31,040 --> 00:15:43,730 And with our Magellan data piercing the clouds and doing radar and getting an idea of its surface, you know, this planet is very volcanic. 135 00:15:44,880 --> 00:15:50,340 And we believe there's indications that it's still volcanic and still kicking out the CO2. 136 00:15:50,880 --> 00:15:55,680 Okay. Now has lost a magnetic field if it had one in the past. 137 00:15:57,060 --> 00:16:06,000 But it has this an enormous thick atmosphere. And and the surface tells us there's hardly any craters that have survived. 138 00:16:06,660 --> 00:16:13,080 And it's resurfaced itself probably many times in its past with huge dome structures, 139 00:16:14,040 --> 00:16:18,600 some of which from our ISA spacecraft that have been at Venus indicate. 140 00:16:18,900 --> 00:16:26,550 These are hot zones. And so they may still be active or at least have been active in the last several thousand years. 141 00:16:27,840 --> 00:16:36,720 So without water. Okay. Venus also is not a likely candidate to day to day to day. 142 00:16:37,380 --> 00:16:43,650 And so our picture of Venus has been a timeline of its creation like Earth. 143 00:16:44,550 --> 00:16:56,220 And then today and then and a lack of understanding of what happened to Venus over the last 3.6 billion years, right in the middle of its evolution. 144 00:16:57,660 --> 00:17:05,489 So we took some of the top climate modellers, those people that have been working out, 145 00:17:05,490 --> 00:17:10,590 you know, the greenhouse effect on Mars and understanding CO2 and its effects here on Earth. 146 00:17:11,310 --> 00:17:22,560 And they turned their attention to Venus because we made a critical measurement, and that measurement is called the D to H ratio. 147 00:17:22,890 --> 00:17:26,430 Okay. Now, D is deuterium. 148 00:17:27,240 --> 00:17:34,230 Deuterium is a hydrogen atom with a neutron stuck into the proton in the in the centre of it. 149 00:17:34,260 --> 00:17:39,750 Okay. So it's a it's a heavy hydrogen called name of deuterium. 150 00:17:40,740 --> 00:17:46,110 And a water molecule could have one of these DS okay. 151 00:17:46,920 --> 00:17:56,430 H2O with with it with a deuterium. Now you can go in our ocean and you can bring out a slug of water and we can go 152 00:17:56,430 --> 00:18:00,990 through that and we can pull out all the water molecules that have deuterium in it. 153 00:18:01,940 --> 00:18:07,490 And we can former ratio so we know what the ratio is on earth today. 154 00:18:09,500 --> 00:18:21,860 And now that we made the measurement of the age at Venus and the D is huge compared to the age, we then realise, Hey, Venus has lost the water. 155 00:18:23,210 --> 00:18:26,390 Deuterium in water molecules makes it heavy. 156 00:18:27,780 --> 00:18:36,599 Water molecules with just H2O are lighter and therefore they go up to higher altitudes and can be stripped away by the solar wind. 157 00:18:36,600 --> 00:18:41,220 And that's what changes the ratio. So let's put the water back. 158 00:18:42,030 --> 00:18:46,200 And so these modellers put that water back on. 159 00:18:46,830 --> 00:18:53,400 They put that water back so that we can do the modelling in this in-between state. 160 00:18:54,570 --> 00:18:59,880 All right, we want to fill that in like we have filled in what our knowledge of the earth is. 161 00:19:00,810 --> 00:19:05,160 So for the Earth, using that same timeline perspective, 162 00:19:05,520 --> 00:19:14,760 after the Earth was created in it cooled down and it was bombarded with more material in a place in a time we call the late heavy bombardment, 163 00:19:15,450 --> 00:19:19,230 bringing a lot of organic material to the surface of the earth. 164 00:19:19,860 --> 00:19:24,690 And in many of these asteroids and comets that hit the earth brought water with them. 165 00:19:25,290 --> 00:19:27,990 So a lot of water and asteroids, it turns out. 166 00:19:28,770 --> 00:19:39,509 And in fact, some some of us believe that perhaps anywhere from 20 to 60% of the water in our oceans today came from this bombardment period, 167 00:19:39,510 --> 00:19:44,069 came from exterior sources rather than interior sources. 168 00:19:44,070 --> 00:19:51,950 So that's hotly debated still. And then life began about 3.6 billion years ago. 169 00:19:51,960 --> 00:19:56,280 So right in the sweet spot where life began here. What the heck was Venus doing? 170 00:19:56,640 --> 00:19:59,820 Okay, so we have the topography of Venus. 171 00:20:00,630 --> 00:20:04,650 We put back the water. We had the initial conditions of the Earth. 172 00:20:05,190 --> 00:20:13,150 But Venus is much closer to the sun. The sun was increasing in intensity in its early time, and we let the models evolve. 173 00:20:13,180 --> 00:20:16,610 But we let the models evolve. 174 00:20:17,040 --> 00:20:27,970 And this is what we found. Venus for perhaps as much as 2 billion years, could have maintained an ocean. 175 00:20:29,970 --> 00:20:38,160 And it's only been in the last 800 million years where the runaway greenhouse effect began to evaporate the ocean. 176 00:20:38,970 --> 00:20:46,480 And because Venus doesn't have a magnetic field, gets stripped by the solar wind and changes the planet forever. 177 00:20:47,840 --> 00:20:52,790 So this tells us Venus could have been habitable in the past. 178 00:20:53,810 --> 00:20:57,410 Even though it rotates slowly. Clouds form. 179 00:20:58,660 --> 00:21:08,980 Huge cloud structures form at the sub solar point, reflecting that sunlight for long periods of time until it's overcome by the increased intensity. 180 00:21:09,820 --> 00:21:15,280 And of course, we don't exactly know the volcanic activity and what's happened, but that has to be factored into. 181 00:21:15,730 --> 00:21:25,120 But these simulations are the start of some new concepts of Venus being habitable when Venus would have been in the habitable zone, 182 00:21:25,360 --> 00:21:27,790 as we've defined it by the astrophysicist. 183 00:21:29,120 --> 00:21:38,659 So today, Venus is not what we would call habitable, even though it's in just at the edge of the habitable zone. 184 00:21:38,660 --> 00:21:42,470 It's the habitable zone is it continues to move outward over time. 185 00:21:42,860 --> 00:21:48,020 The sun's intensity is going to increase. It's what our stars do. 186 00:21:48,980 --> 00:21:59,180 And and it's been stripped of material like crazy, even though there's an enormous amount of atmosphere and it keeps getting dumped in. 187 00:21:59,810 --> 00:22:03,230 The lack of a magnetic field is stripping this atmosphere away. 188 00:22:03,800 --> 00:22:08,510 So this planet is going to evolve very, very differently in the future. 189 00:22:09,530 --> 00:22:13,100 Of course, here's our blue marble teeming with life. 190 00:22:14,420 --> 00:22:20,270 And as we talked about over its history, it's had quite a changing climate. 191 00:22:21,600 --> 00:22:31,480 In fact, as a planetary scientist, I can tell you the climate has done nothing but change OC sometimes faster than at other times. 192 00:22:31,500 --> 00:22:39,780 So it's really all about the rate of change. And it has to do with a variety of, of, of how life has taken hold. 193 00:22:40,320 --> 00:22:49,350 How life has produced oxygen. And how that's changed the overall chemistry of of our atmosphere over time. 194 00:22:50,310 --> 00:22:56,820 But when we tease out a couple parts to the to to the earth and we look back. 195 00:22:57,780 --> 00:23:02,250 We find that the Earth went through some enormous changes in its climate. 196 00:23:03,270 --> 00:23:04,920 There's two eras here. 197 00:23:05,970 --> 00:23:21,600 One at about 750 million years ago and another one at 2.4 billion years ago where the climate was so severe that the ocean started to frost over. 198 00:23:22,660 --> 00:23:26,110 We call that time period. Snowball Earth. 199 00:23:26,530 --> 00:23:32,890 Okay. And we have geological indications that the Earth went through this period. 200 00:23:33,250 --> 00:23:39,250 Snowball Earth. Okay. And and fortunately, life survived through that. 201 00:23:39,520 --> 00:23:45,490 Earth looked more like Europa than it did the blue marble that we know of it today. 202 00:23:46,840 --> 00:23:57,820 But fortunately, life made it through. And right now, today, Earth has a very nice magnetic field that is protecting it against the solar wind. 203 00:23:58,750 --> 00:24:05,620 And it it is what we believe is an important element for the survival of life in the long run. 204 00:24:05,740 --> 00:24:09,350 Honour on earth. Let's go to Mars. 205 00:24:10,840 --> 00:24:19,270 So Mars is much larger than the moon, but certainly smaller than the Earth's by half the size of the earth. 206 00:24:19,300 --> 00:24:24,200 All right. And it's a runt in terms of terrestrial planets. 207 00:24:25,100 --> 00:24:29,630 And it's a front because of Jupiter. It's a runt because of Jupiter. 208 00:24:30,080 --> 00:24:33,500 And in fact, between Mars and Jupiter is the asteroid belt. 209 00:24:34,130 --> 00:24:39,590 This is an area of debris, of material that's trying to become a planet. 210 00:24:39,980 --> 00:24:49,700 But it never happened. Making planets is all about the accretion process where objects collide and then they 211 00:24:49,700 --> 00:24:56,000 reform and then they collide with other objects and reform into larger and larger objects. 212 00:24:56,930 --> 00:25:07,520 But in the asteroid belt, which is so close to Jupiter, these collisions occur, and then Jupiter pulls them apart because of its gravity. 213 00:25:08,760 --> 00:25:11,430 So the big guy on the block, Jupiter, 214 00:25:11,760 --> 00:25:24,600 is creating an environment where Mars is a runt and the asteroid belt is like going back in time and looking at material that's that. 215 00:25:24,600 --> 00:25:32,040 It's the very beginning of accreting going from going from Planetesimals to Protoplanets to then planets. 216 00:25:33,270 --> 00:25:38,010 And we have examples of what those those objects are. And we visited with Dawn. 217 00:25:38,400 --> 00:25:48,300 We were at Vesta and Ceres, two major and members of the asteroid belt that are providing tremendous information for us. 218 00:25:49,660 --> 00:25:59,790 So we've had a number of missions at Mars. And so we can geologically tease out what's occurred over time on Mars. 219 00:26:00,870 --> 00:26:03,510 So in the very early stage, the No archaean. 220 00:26:04,630 --> 00:26:15,130 This is an area of time for which it's clear to us Mars had an enormous amount of water early on in its history. 221 00:26:15,910 --> 00:26:26,660 Early on in its history. In fact, two thirds in the northern hemisphere, we believe, was under water at places it was a mile deep or more. 222 00:26:27,710 --> 00:26:31,610 Okay. And then it went through. Rapid climate change. 223 00:26:32,540 --> 00:26:35,629 Now, we don't know exactly why. 224 00:26:35,630 --> 00:26:43,070 We have some indications of that. Perhaps along the way it had a magnetic field and we know it did. 225 00:26:43,280 --> 00:26:48,380 It lost that field and the solar wind started to strip that that field away. 226 00:26:49,800 --> 00:26:54,060 We're not quite sure. But today it's very dry and arid. 227 00:26:54,420 --> 00:27:03,420 Okay. The pressure the pressure on Mars is about 1% or less than the pressure here on Earth. 228 00:27:04,680 --> 00:27:08,520 Now to give you an indication of the size of the ancient ocean. 229 00:27:09,150 --> 00:27:20,310 This is a mercator map of Mars, and it shows where our what we've landed on Mars successfully that interrogated it, looked at it. 230 00:27:21,060 --> 00:27:24,060 And the blue areas are the lowlands. 231 00:27:24,720 --> 00:27:32,610 This is where the water would be. And the red and the white areas are the high elements, the the high features on it. 232 00:27:32,970 --> 00:27:39,450 And so, as you can see, significant part of the northern hemisphere is where the ancient ocean is. 233 00:27:39,900 --> 00:27:46,110 And a lot of our missions are going right to the shoreline of the ancient oceans. 234 00:27:46,800 --> 00:28:00,540 Those places where life may have started. And and indeed, curiosity, which you can see right over here is is in Gale Crater. 235 00:28:01,860 --> 00:28:06,090 We're about ready to land another mission. It's called Insight. 236 00:28:06,630 --> 00:28:11,280 And Insight is just a few degrees north of curiosity. 237 00:28:11,970 --> 00:28:18,240 Insight will be in the ancient ocean. Curiosity is in a crater called Gale Crater. 238 00:28:18,930 --> 00:28:27,450 Gale Crater, which indeed its rim was breached with water from this ocean pouring into the crater. 239 00:28:29,150 --> 00:28:31,130 And so when Curiosity landed. 240 00:28:32,940 --> 00:28:43,890 And began to drill into Mars and then allow us to take that drilled filings and bring it in and then tease out the mineralogy, 241 00:28:44,460 --> 00:28:53,430 tease out the chemical composition. The first thing we saw, which for many of us, and I'll be the first to admit I was one of them. 242 00:28:53,550 --> 00:29:00,960 I was shocked. When we drilled into the ground, grey material came out, you know, 243 00:29:01,170 --> 00:29:08,430 that this oxidised surface right below the surface is what Mars is really like in its past. 244 00:29:08,700 --> 00:29:17,050 It's grey Mars. And those soils we brought into our instruments and we measured them. 245 00:29:18,460 --> 00:29:24,190 And they had carbon hydrogen, oxygen, nitrogen, phosphorus and sulphur. 246 00:29:24,370 --> 00:29:27,490 That's all the elements we are made of. 247 00:29:27,820 --> 00:29:35,350 It's all the right stuff. And it's sitting in a region that was full of water. 248 00:29:36,790 --> 00:29:44,650 And in fact, the sediments in this in this area that we can tease out tells us the water. 249 00:29:45,190 --> 00:29:51,720 If we went back three and a half to 3.8 billion years, we could drink it. 250 00:29:53,140 --> 00:29:57,160 If we brought microbes and put them in there, they would have survived. 251 00:29:58,090 --> 00:30:07,510 So Mars, its atmospheric pressure was much larger to be able to support water as a liquid. 252 00:30:08,670 --> 00:30:13,590 The heat had to be extensive compared to what it is today. 253 00:30:14,570 --> 00:30:20,690 One day on Mars is a change of temperature of about 170 degrees Fahrenheit. 254 00:30:20,870 --> 00:30:26,540 That's one day. It's an enormous change. It's not like that Mars is past. 255 00:30:27,450 --> 00:30:32,610 Mars was a blue planet. When Earth was a blue planet. 256 00:30:33,120 --> 00:30:35,400 When Venus was a blue planet. 257 00:30:37,770 --> 00:30:48,450 All three of those planets early on in their history had plenty of water and had environments that we would call habitable, 258 00:30:49,470 --> 00:30:52,440 whether they were in the habitable zone or not. 259 00:30:54,060 --> 00:31:04,440 And so we recognise how complicated this system is and it requires knowledge of the atmosphere, the knowledge of the composition, 260 00:31:04,890 --> 00:31:12,390 the knowledge of energy input, and the ability to maintain an environment that would provide us liquid water. 261 00:31:13,470 --> 00:31:22,320 So what's happened to Venus or sorry, Mars over its history is now being teased out by a spacecraft called Maven. 262 00:31:23,580 --> 00:31:27,840 So Maven's been or orbiting Mars now for several years. 263 00:31:28,740 --> 00:31:34,740 And that solar wind is just ripping the upper atmosphere away. 264 00:31:36,170 --> 00:31:41,660 In fact, we see what Mars actually from Curiosity is actually fairly human. 265 00:31:42,440 --> 00:31:49,200 There's a water cycle on Mars. It's it's not like anything like ours, but it's measurable. 266 00:31:49,580 --> 00:31:55,190 Okay. It snows during the winter again, not just CO2, but water. 267 00:31:56,090 --> 00:32:03,050 We believe that under certain conditions, craters that have opened up aquifers, 268 00:32:03,350 --> 00:32:11,510 that those aquifers weep when the sunlight has sublimated the ice plugs and the water pours down the crater size. 269 00:32:12,130 --> 00:32:20,350 The length of the crater. And we measure those and they're all over the place recently with an E submission. 270 00:32:21,580 --> 00:32:27,790 We've teased out an underground lake in the in the southern hemisphere, 271 00:32:27,790 --> 00:32:33,550 which I think is the start of really looking at the underwater resources on Mars. 272 00:32:34,380 --> 00:32:42,250 It was, although Mars has lost its ocean. A lot of that water is into the ground and into the aquifer systems. 273 00:32:43,010 --> 00:32:50,200 And where there's water, there's potentially life. Now Curiosity is also measuring methane. 274 00:32:51,770 --> 00:32:57,730 It's measuring methane above any background. And that methane is very cyclic. 275 00:32:58,690 --> 00:33:02,200 Methane can be generated by biology. 276 00:33:03,160 --> 00:33:15,100 Okay. And methane can be a biotic generated with olivine and and an intense heat and water deep in its core can generate methane that can leak out. 277 00:33:16,120 --> 00:33:22,140 And so we see blooms of methane coming from certain regions. 278 00:33:22,210 --> 00:33:27,080 Curiosity, which is sitting in this hole called Great Gale Crater. 279 00:33:27,100 --> 00:33:34,930 During the day, it measures methane. But the wind patterns during the day are leaving the crater. 280 00:33:35,740 --> 00:33:44,110 And so the methane that's generated many, many degrees difference away aren't getting into Gale Crater. 281 00:33:44,350 --> 00:33:46,510 It's got to be leaking through the soils. 282 00:33:47,530 --> 00:33:58,240 So is is curiosity sitting over an aquifer where there's life and and methane is being generated is leaking through the soils. 283 00:33:59,770 --> 00:34:03,580 We don't know. Or it could be generated, Abiotic. 284 00:34:03,850 --> 00:34:09,490 We just don't know. So these are really exciting measurements. 285 00:34:09,670 --> 00:34:13,330 That tells us a lot different story about about Mars. 286 00:34:15,370 --> 00:34:20,750 So what about the northern polar cap? This is a permanent polar cap. 287 00:34:21,590 --> 00:34:28,580 You can get its spectra and you can measure also water. 288 00:34:29,670 --> 00:34:35,730 So what we have is a veneer of CO2 over an enormous. 289 00:34:37,020 --> 00:34:41,340 Water ice cap. Okay. An enormous water ice cap. 290 00:34:41,990 --> 00:34:47,520 And here's the radar observations of the ice cap right here down in the corner, right hand corner. 291 00:34:48,030 --> 00:34:54,260 So you can see the the layers of material that's built up and it's huge. 292 00:34:55,250 --> 00:35:00,140 You know, some of these places that a kilometre of an eye of ice over very large regions. 293 00:35:01,370 --> 00:35:07,920 It's a large amount of water with this veneer of CO2 that's actually keeping that water from sublimating. 294 00:35:09,480 --> 00:35:12,760 But what will happen over time? We've started model this. 295 00:35:12,810 --> 00:35:16,440 So if we increase the temperature of Mars. Okay. 296 00:35:17,010 --> 00:35:26,420 So here we have a time in the future. Where the temperature because the sun's temperature is increasing the heat. 297 00:35:26,440 --> 00:35:30,430 Mars will receive will increase and the ice. 298 00:35:31,430 --> 00:35:36,110 Dry ice, CO2 ice veneer will sublimate. 299 00:35:37,090 --> 00:35:47,440 That will increase the atmosphere, which increases its greenhouse effect, which as temperature continues to rise, will melt the water. 300 00:35:47,800 --> 00:35:51,700 And one seventh of Mars is ancient. 301 00:35:51,730 --> 00:35:56,190 Ocean will return. We'll return. 302 00:35:57,820 --> 00:36:02,240 And it will look like that. Okay. 303 00:36:03,650 --> 00:36:13,910 So now we have. Our modern views of these planets and an inkling from the modelling that we've done of their past. 304 00:36:14,870 --> 00:36:19,100 To be able to see how they've evolved. 305 00:36:20,340 --> 00:36:26,520 Not in a habitable zone, but in a habitable state. 306 00:36:27,980 --> 00:36:31,720 Okay. Mercury never had a shot at it. 307 00:36:32,980 --> 00:36:39,040 Venus, we believe, as it evolved, moved into a habitable state because of the water it had. 308 00:36:39,580 --> 00:36:43,750 But then due to a runaway greenhouse effect, it lost it. 309 00:36:45,250 --> 00:36:50,080 Earth almost popped out of a habitable state twice. 310 00:36:51,360 --> 00:36:57,360 Snowball Earth almost popped it out. Okay, but it managed to stay in a habitable state. 311 00:36:58,340 --> 00:37:03,350 We're now well situated in the habitable zone or in the habitable state. 312 00:37:04,610 --> 00:37:08,360 But over time, that must change. 313 00:37:09,360 --> 00:37:14,220 Due to natural circumstances unless we do climate engineering or something else. 314 00:37:15,090 --> 00:37:20,280 But when Earth moves out of the habitable state, we better be on Mars. 315 00:37:20,890 --> 00:37:27,120 Okay, so Mars is moved through a habitable state. 316 00:37:27,300 --> 00:37:31,650 It's dry and arid, although a lot of water is trapped under the ground. 317 00:37:32,490 --> 00:37:42,660 And indeed, as we talked about, we envision through the modelling that we've done that it will pop back into becoming habitable. 318 00:37:43,650 --> 00:37:52,710 So this has really changed our view of how the terrestrial planets have evolved over time and where life exists or could have exist. 319 00:37:53,370 --> 00:37:58,590 So life on Mars may be just holding on. 320 00:38:00,030 --> 00:38:03,750 Maybe tenuously there or not. 321 00:38:04,750 --> 00:38:11,770 It's a toss up, but it had plenty of time and the right environment in its past. 322 00:38:11,890 --> 00:38:14,290 To have had life. To have had life. 323 00:38:15,130 --> 00:38:24,790 So our plans are bringing back samples and interrogating the rock record, looking for why Mars went through the rapid climate change it did. 324 00:38:25,360 --> 00:38:29,590 And if we get lucky, might have some sort of indication of life. 325 00:38:31,260 --> 00:38:41,610 There are 4700 minerals you can define here on Earth, and three or 400 of them can only be done if you've got life. 326 00:38:42,710 --> 00:38:47,480 So the rock record can tell us an enormous amount about its past. 327 00:38:48,800 --> 00:38:52,300 And we need to get it into our laboratories where we can study it. 328 00:38:52,310 --> 00:39:02,690 And we're on the cusp of doing that. The mission that's going to Core Rock will launch in 2020 land in 21, and over the next several years, 329 00:39:02,690 --> 00:39:07,640 NASA, ESA and some of the other agencies are getting together to bring those rocks back. 330 00:39:08,660 --> 00:39:15,380 And it will be critical because it will tell us everything about the past and allow us. 331 00:39:16,380 --> 00:39:20,520 To figure out its future and the future of Earth. 332 00:39:22,110 --> 00:39:29,820 Okay. So I hope you see what I talked about that we are so lucky to have Venus. 333 00:39:31,920 --> 00:39:36,750 And Mars. Because what's happened on Venus can happen on Earth. 334 00:39:37,200 --> 00:39:40,580 What's happened on Mars can happen on Earth. Okay. 335 00:39:41,370 --> 00:39:49,660 Comparative climatology. Is critical for us to continue to do so that we can understand the fate of this planet. 336 00:39:51,210 --> 00:39:55,260 While we're understanding the fate of the sister planets that we have. 337 00:39:56,520 --> 00:40:03,450 Another fantastic thing happened over the last several years, in the last ten years, in particular, 338 00:40:04,110 --> 00:40:10,950 completely changing the planetary scientists view of what goes on beyond the snow line. 339 00:40:12,390 --> 00:40:16,290 And that is we have found ocean worlds. 340 00:40:17,410 --> 00:40:25,420 Okay. Entire bodies with huge amounts of water around the giant planets. 341 00:40:26,110 --> 00:40:29,450 Now the giant planets Jupiter, Saturn, Uranus and Neptune. 342 00:40:29,470 --> 00:40:34,040 They have water in them. There's plenty of water out there. 343 00:40:34,290 --> 00:40:39,960 Okay. But to have it as liquid water, you have to go to the moons. 344 00:40:41,150 --> 00:40:51,360 That's where we're going to be finding it. So if we go to the Jupiter environment, here's one of the fabulous observations from Juno of Jupiter. 345 00:40:51,380 --> 00:40:55,730 This is real, a real image taken from a really unique perspective. 346 00:40:56,210 --> 00:41:06,610 It's a beautiful planet. And we're teasing out a lot of a lot of things about Jupiter, and we know a lot about its Galilean moons. 347 00:41:07,330 --> 00:41:16,270 These are the moons IO, Europa, Ganymede and Callisto that Galileo saw in 1611. 348 00:41:17,800 --> 00:41:22,209 Now we have visited them. Now we understand them in many different ways. 349 00:41:22,210 --> 00:41:26,590 And and it's just spectacular that what we have found out. 350 00:41:27,980 --> 00:41:31,640 There is a habitable state that exists. 351 00:41:32,760 --> 00:41:39,360 In this region around Mars and Europa is right in the middle of it. 352 00:41:40,260 --> 00:41:43,430 Okay. When we look at IO. 353 00:41:44,000 --> 00:41:48,290 IO is very volcanic. Very volcanic. 354 00:41:48,870 --> 00:41:54,980 Okay. And in fact, let me show you an image from Juno of IO. 355 00:41:55,990 --> 00:41:59,290 In the infrared. Okay. And. 356 00:41:59,330 --> 00:42:05,170 And there it is. At any one time, there are 100 active volcanoes on IO. 357 00:42:05,470 --> 00:42:10,480 IO is about the size of our own moon. This is not a small object. 358 00:42:10,930 --> 00:42:15,070 It's a very large object. Okay. It's very volcanic. 359 00:42:16,630 --> 00:42:21,130 And that's because of the tidal forces. From Jupiter. 360 00:42:22,060 --> 00:42:29,680 These moons are in slightly elliptical orbits. And so as they orbit Jupiter, there's the Perry Centre. 361 00:42:29,800 --> 00:42:38,680 That's where it's closest to Jupiter. Jupiter squeezes it and then it moves out to its epicentre and the gravity is less. 362 00:42:39,900 --> 00:42:48,330 And so when you look at these moons and they get tugged and pull and squeezed, that heat is got to go somewhere. 363 00:42:49,260 --> 00:42:55,410 Now, all these moons when they were created had a huge ice crossed over them. 364 00:42:56,250 --> 00:43:01,760 Io's ice crust is gone. Och, it it. 365 00:43:01,980 --> 00:43:05,570 It went. Billions of years ago. 366 00:43:06,020 --> 00:43:11,730 All right. But not Europa, Ganymede or Callisto. 367 00:43:13,140 --> 00:43:18,030 Now. Ganymede is our largest moon. In the solar system. 368 00:43:18,600 --> 00:43:24,440 In fact, it generates its own magnetic field. And there's indications that it has. 369 00:43:25,540 --> 00:43:32,990 And under crust ocean. Now we believe that ocean is deep, but it has communicated to the surface. 370 00:43:33,910 --> 00:43:37,090 We see the cratering record on Ganymede. 371 00:43:37,870 --> 00:43:42,400 There's a lot of craters there, but a lot more have been covered up over time. 372 00:43:43,670 --> 00:43:46,760 And that's because when we look at Callisto. 373 00:43:47,730 --> 00:43:55,170 It also has a huge icy veneer over a rocky interior body. 374 00:43:56,910 --> 00:44:00,510 And perhaps it had an ocean of water in its past. 375 00:44:01,650 --> 00:44:11,240 But that hasn't come to the surface. This body shows us the impact rate that all these satellites should have had. 376 00:44:12,150 --> 00:44:15,840 And it is one of the most cratered objects in the solar system. 377 00:44:16,920 --> 00:44:21,720 And yet IO has no craters. Europa only has a couple. 378 00:44:23,210 --> 00:44:30,050 You know, Danny made a couple hundred and millions on Callisto. 379 00:44:30,410 --> 00:44:36,470 Okay. And that's because these bodies have erased them. 380 00:44:37,710 --> 00:44:41,700 The ocean has communicated to the surface. 381 00:44:43,400 --> 00:44:47,150 Ganymede's too cold. IO is too hot. 382 00:44:47,690 --> 00:44:52,110 But Europa. You know, it's just right. 383 00:44:52,140 --> 00:44:57,450 It's right in a habitable state. So let me tell you what we know about Europa. 384 00:44:58,440 --> 00:45:02,160 Here it is. You can see the cracks, beautiful cracks. 385 00:45:04,390 --> 00:45:09,250 Coming from these cracks we now believe are huge geysers. 386 00:45:09,940 --> 00:45:18,710 We now have measured these geysers from Hubble. Now, Europa is slightly smaller than our moon, so it has enormous gravity associated with it. 387 00:45:19,180 --> 00:45:25,060 And yet we have found some of these geysers going up 400 kilometres. 388 00:45:26,010 --> 00:45:29,510 Yeah, yeah, yeah. It's exactly what I said. Okay? 389 00:45:30,030 --> 00:45:35,129 I mean, I don't know of anything that. That's a wall of water that goes up to space station. 390 00:45:35,130 --> 00:45:39,540 I haven't seen that on this globe yet. And we think this is a water world. 391 00:45:39,660 --> 00:45:46,230 Okay. But we have flown through those with with Galileo. 392 00:45:46,800 --> 00:45:53,280 And we recently discovered that data only because we didn't know what we were looking at at the time. 393 00:45:54,300 --> 00:45:59,910 But over time, as we understand what these signatures tell us, we can go back in the data and find it. 394 00:46:00,540 --> 00:46:03,900 And that's why Galileo flew through this plume. 395 00:46:04,530 --> 00:46:09,000 And it's clearly obvious that's what it is. It's got all the indications of it. 396 00:46:09,810 --> 00:46:17,520 It's unbelievable. And from Galileo data, primarily, we can tease out the size of this ocean. 397 00:46:19,280 --> 00:46:23,270 It has twice the amount of water than there is on this planet. 398 00:46:24,190 --> 00:46:27,460 And yet this object is about the size of the moon. Okay. 399 00:46:28,610 --> 00:46:36,880 So it has an icy crust. With cracks where the ocean has communicated to the surface and is communicating now. 400 00:46:37,660 --> 00:46:40,960 It's done it in the past because it's eliminated its craters. 401 00:46:41,880 --> 00:46:45,000 And it's doing it now. And we see that with Hubble. 402 00:46:45,660 --> 00:46:53,460 We can't quite tease out yet what the circumstances are that open and close these cracks to allow this water to come out. 403 00:46:54,270 --> 00:47:01,530 But with our next mission to to Europa called the Europa Clipper, it's designed to measure the ice thickness. 404 00:47:02,520 --> 00:47:09,090 I think we'll see the ice thickness anywhere from ten kilometres to right at the surface all over the place. 405 00:47:09,420 --> 00:47:15,120 Okay. As the ocean continues to communicate with the surface, there's even some indications. 406 00:47:16,160 --> 00:47:19,310 That as these cracks open up, the ice has to go somewhere. 407 00:47:19,610 --> 00:47:23,480 There's some subduction of of that has been determined by some of these 408 00:47:23,510 --> 00:47:27,740 observations from Galileo of one ice plate moving underneath the other ice lake. 409 00:47:29,460 --> 00:47:33,750 That's called plate tectonics here on Earth. That's about a living planet. 410 00:47:34,080 --> 00:47:39,420 Okay. And so this moon has a lot to offer us. 411 00:47:39,990 --> 00:47:49,720 Okay. And the really great thing is it's been like this for 4.6 billion years time. 412 00:47:50,170 --> 00:47:55,360 It's got okay. And that time is critical. 413 00:47:55,450 --> 00:47:59,540 If it had all the right ingredients. To be able to spy on life. 414 00:48:00,440 --> 00:48:04,880 So we got a really good shot at finding life on bodies like this. 415 00:48:06,060 --> 00:48:08,760 And some people say, well, that's only going to be microbial. 416 00:48:09,270 --> 00:48:17,010 It could be complex life on Europa because of the length of time that that that's occurred there. 417 00:48:17,100 --> 00:48:22,950 I would not rule that out. As we move further out, Saturn. 418 00:48:24,090 --> 00:48:30,150 You know, we've really looked at Saturn in many ways. And one of the startling things about Saturn is looking at this moon. 419 00:48:30,660 --> 00:48:39,960 This moon is Enceladus. And Enceladus is what really turned our attention to what's going on on these bodies, because it's got geysers. 420 00:48:40,800 --> 00:48:44,320 And these geysers are coming from huge cracks in the southern hemisphere. 421 00:48:44,340 --> 00:48:49,490 There's four or five of these cracks, actually, we call them tiger stripes. 422 00:48:49,500 --> 00:48:53,760 They look like tiger stripes on on the side of a tiger. 423 00:48:54,450 --> 00:48:59,550 And they're not just. They're not just little geezers. 424 00:48:59,820 --> 00:49:04,950 They are actually walls of water that are pouring out of the body. 425 00:49:05,370 --> 00:49:08,640 Now, this is a small moon, about 300 kilometres in size. 426 00:49:09,510 --> 00:49:13,680 And and and it it it it also is suffering tidal forces. 427 00:49:13,680 --> 00:49:27,420 We can see the water flowing out of these when the body is close to the planet is much less then when Enceladus is on the furthest away from Saturn. 428 00:49:27,900 --> 00:49:31,680 Okay. Where the water pours out. 429 00:49:32,700 --> 00:49:40,290 So we can even see the tidal interactions because of the elliptical orbit demonstratively on, 430 00:49:40,800 --> 00:49:49,620 on Enceladus and it's because we've flown through it and we measured the magnetic field and the plasma wave data and, 431 00:49:49,620 --> 00:49:52,350 and tasted this water as we went through it, 432 00:49:53,010 --> 00:50:01,410 giving us all the data we needed to go back and analyse the Galileo data that allowed us to see that we actually flew through a plume on Europa. 433 00:50:01,470 --> 00:50:05,120 We just didn't know it in 1997. Okay. 434 00:50:06,260 --> 00:50:12,830 Now, about 98% of all the water that comes out of the geysers falls back on this little moon. 435 00:50:14,400 --> 00:50:19,580 But a few percent of it actually escapes and it forms the E-Ring. 436 00:50:20,530 --> 00:50:24,880 Forms the ring around Saturn. So here's the E ring. 437 00:50:25,330 --> 00:50:27,850 Okay. And there is indeed. And Solidus. 438 00:50:29,460 --> 00:50:36,810 And so we really believe we understand now what's happening because we've also as we've flown through the plume. 439 00:50:39,090 --> 00:50:42,570 Measured little bits of rock. Okay. 440 00:50:43,440 --> 00:50:50,250 And we've teased apart what the composition is, and we've looked at the composition of the plume. 441 00:50:51,150 --> 00:51:01,770 And we believe that's all very characteristic of hydrothermal vents that is sitting on the bottom of the ocean in the rocky material on in Solidus. 442 00:51:02,220 --> 00:51:12,090 So that means the rock is is interfacing with the water, which then is capped with an icy crust. 443 00:51:12,600 --> 00:51:17,400 And cracks are allowing this heated water to pour out of the planet, 444 00:51:18,240 --> 00:51:30,209 where outside the body is zero pressure and a pressure of the water that's building up inside, under the cross is building up. 445 00:51:30,210 --> 00:51:34,440 And when these cracks open up, it's going to just take off, okay? 446 00:51:35,280 --> 00:51:40,040 It's just going to take off. And that's what's happening. In a similar way. 447 00:51:41,560 --> 00:51:46,700 On Europa. I know what Europa's surface. 448 00:51:47,440 --> 00:51:51,850 At the bottom of that ocean looks like. I know what it looks like. 449 00:51:52,720 --> 00:51:56,110 All I have to do is look at IO. 450 00:51:56,800 --> 00:52:00,100 Okay. That's got to be what's happening. 451 00:52:01,150 --> 00:52:05,380 The bottom of the ocean of Europa hydrothermal vents. 452 00:52:06,480 --> 00:52:10,050 Heating the water. It's creating this environment. 453 00:52:10,960 --> 00:52:20,060 And we're finding it on this man to. We also suspect several other moons with water layers. 454 00:52:22,320 --> 00:52:26,890 And another spectacular moon of Saturn. Is. 455 00:52:27,780 --> 00:52:33,300 Tighten. Now. Titan is unbelievable. 456 00:52:33,930 --> 00:52:38,220 It is a huge body. It is bigger than the planet Mercury. 457 00:52:39,680 --> 00:52:43,760 Its atmosphere is about twice the atmospheric pressure than we have here. 458 00:52:44,030 --> 00:52:52,370 Dominated by nitrogen. Dominated by nitrogen as trace gases of of methane and ethylene. 459 00:52:53,720 --> 00:52:58,510 All right. And it has bodies of liquid. 460 00:52:58,990 --> 00:53:07,180 Okay. This is a radar image going through the smog, smoggy environment of the atmosphere, bouncing off the surface, coming back. 461 00:53:07,780 --> 00:53:11,080 And the black and blue areas are are. 462 00:53:12,120 --> 00:53:19,280 Very. Laminar very still compared to the rough terrain. 463 00:53:19,980 --> 00:53:25,200 And we now know what that is. These are liquid methane lakes. 464 00:53:26,550 --> 00:53:36,500 Liquid liquid methane lakes. So. Titan has spurred a whole new look at life. 465 00:53:36,890 --> 00:53:48,590 All right. You know, when I talked about life, those three attributes metabolises reproduces, evolves and and for the metabolism we say water. 466 00:53:49,850 --> 00:53:54,080 Wonder if you didn't have water. Wonder if it was another liquid. 467 00:53:54,740 --> 00:54:00,920 Okay. Wonder if there's life that doesn't need water but still needs the liquid. 468 00:54:01,490 --> 00:54:12,140 Okay. And so the bottom line is it could be life, but not as we know it. 469 00:54:12,950 --> 00:54:16,959 And if there's any place to go look for. Life. 470 00:54:16,960 --> 00:54:20,140 Not like us. It's on Titan. 471 00:54:21,140 --> 00:54:26,150 It's on Titan. Okay. What a fabulous world. 472 00:54:27,290 --> 00:54:32,419 So we haven't done all the modelling we needed to in the outer part of the solar system. 473 00:54:32,420 --> 00:54:38,120 But if we tease out. What the habitable states are for these bodies. 474 00:54:38,810 --> 00:54:45,020 We see that I chose to call too hot. We see Ganymede and in Callisto's too cold. 475 00:54:45,410 --> 00:54:52,240 And we now have a series of moons. That is right there in the habitable state. 476 00:54:52,900 --> 00:54:56,650 Those are the moons that we're going to emphasise and go after in the future. 477 00:54:57,990 --> 00:55:04,770 So we now have the basis for a number of very important missions coming up that we're that we're thinking about doing, 478 00:55:04,770 --> 00:55:10,560 some of which we're building, and we will execute like Mars sample return, like going back to Europa. 479 00:55:11,370 --> 00:55:14,790 We have some things that we're studying in terms of getting back to Titan. 480 00:55:15,690 --> 00:55:20,550 And jumping around on Titan with a quad helicopter, making all kinds of measurements. 481 00:55:21,600 --> 00:55:33,570 And in surveying these bodies like like we've never done before, now that we have this basis, we then can go and begin to look at exoplanets. 482 00:55:34,580 --> 00:55:39,440 And tease out what's happening in in other solar systems. 483 00:55:40,070 --> 00:55:43,340 And we are finding absolutely amazing things. 484 00:55:43,340 --> 00:55:52,820 So here's Kepler. Kepler works by looking at a large number of stars, by just looking at the intensity of the light. 485 00:55:53,910 --> 00:55:57,210 And we just look at the intensity over and over again. Okay. 486 00:55:57,930 --> 00:56:06,090 So when the intensity changes over time and in a periodic way, it tells us there may be a planet there. 487 00:56:06,840 --> 00:56:11,600 Okay, so here's an example of a star. For which. 488 00:56:12,780 --> 00:56:19,650 When we look at the intensity of the light, as the planet passes, that intensity dips. 489 00:56:20,710 --> 00:56:27,780 And a bigger planet. Would obscure more light from the star, giving us a bigger dip. 490 00:56:29,330 --> 00:56:30,979 So this is how Kepler works. 491 00:56:30,980 --> 00:56:42,320 It takes a look at an area of the sky, large area of the sky where there were 125,000 stars and did nothing but measure their intensity over time. 492 00:56:42,650 --> 00:56:47,780 Okay. And it's from those curves, these very simple light curves. 493 00:56:48,530 --> 00:56:53,340 We can tease out their planets. How big they are. 494 00:56:54,460 --> 00:57:04,920 And how far away from the star they are. The further away they are from the star, the longer that light curve will be low before it goes back up. 495 00:57:05,280 --> 00:57:12,649 Okay. And so at at the end of Kepler, looking at this region of sky, 496 00:57:12,650 --> 00:57:16,580 it's now looking at other regions of sky, and it's nearly run out of fuel, unfortunately. 497 00:57:17,030 --> 00:57:22,320 It's just been a remarkable mission. We can determine. 498 00:57:24,160 --> 00:57:29,630 What are the most common planets? Now, I don't know about you, but this shocked me. 499 00:57:30,410 --> 00:57:35,220 This absolutely shocked me. I thought we were going to see Jupiter's. 500 00:57:35,590 --> 00:57:39,290 Okay, I thought Jupiter's. We're going to be all over the place. 501 00:57:40,160 --> 00:57:44,920 They're not. They're actually uncommon, okay? 502 00:57:45,760 --> 00:57:49,560 They're actually uncommon. And as you can see here. 503 00:57:50,690 --> 00:58:00,740 The most common planets are super earths or what we also call sub Neptune size sub Neptune size a super-Earth. 504 00:58:01,490 --> 00:58:05,620 We don't have a super-Earth. In our solar system. 505 00:58:06,430 --> 00:58:16,970 This is a rocky body. Okay. That may be up to five, maybe ten times the mass of the earth. 506 00:58:17,570 --> 00:58:23,120 Now, that doesn't make it ten times the size of the earth because gravity will crunch it down. 507 00:58:23,450 --> 00:58:26,510 It might be twice the size of the earth. Okay. 508 00:58:28,310 --> 00:58:34,310 But the gravity can be enormous on these bodies and those are the most common planets. 509 00:58:35,390 --> 00:58:41,240 That's a shocker. We also can do follow up observations of these super-Earths. 510 00:58:42,300 --> 00:58:46,550 And we can see their size. We know what their size is. 511 00:58:46,560 --> 00:58:55,139 We know what the orbital dynamics are. And and from Doppler shifts and radial velocity measurements, 512 00:58:55,140 --> 00:59:00,780 we can actually get the density of the planet in the only way we can get the density to work out is if we add water. 513 00:59:01,740 --> 00:59:05,400 And so some of these super-Earths may be water worlds. 514 00:59:06,430 --> 00:59:09,700 And I don't mean a little water. I mean a lot of water. 515 00:59:10,000 --> 00:59:18,310 Okay. With extensive atmospheres. Things we can get spectra of and really tease out and understand. 516 00:59:19,090 --> 00:59:24,280 And these are some of the most common extrasolar planets out there. 517 00:59:24,670 --> 00:59:28,930 Okay. And of course, that water is such a key element. 518 00:59:29,830 --> 00:59:38,240 Is such a key element. So most recently a discovery was made and you may have heard about it. 519 00:59:38,900 --> 00:59:45,650 It's called Trappist one. Trappist one is a dwarf star. 520 00:59:46,760 --> 00:59:50,400 It's not very far away. It's 40 light years away. Okay. 521 00:59:50,720 --> 00:59:54,650 It's actually in our neighbourhood, just around the block, 40 light years. 522 00:59:55,760 --> 01:00:04,790 And it had seven planets. And so when the astronomers do the normal calculations of, okay, the heat from that star, 523 01:00:04,790 --> 01:00:08,460 you know, with what these kind of planets could have water on them. 524 01:00:08,480 --> 01:00:13,820 So it's ice and water, liquid and vapour, you know, where's that habitable zone? 525 01:00:14,690 --> 01:00:17,720 Three of the seven planets could be in that habitable zone. 526 01:00:17,930 --> 01:00:21,050 Absolutely fantastic. Absolutely fantastic. 527 01:00:21,830 --> 01:00:26,770 Okay. So here's the other dimension of that that we now can bring in. 528 01:00:28,420 --> 01:00:33,160 These planets are really close to the star because the star is pretty dim. 529 01:00:33,850 --> 01:00:37,030 It's an m-class star and it's really active. 530 01:00:37,900 --> 01:00:45,720 It has an enormous solar wind with flares and coronal mass ejections maybe every day. 531 01:00:45,760 --> 01:00:49,000 And it's hammering these planets. Okay. 532 01:00:49,540 --> 01:00:53,379 This is not a nice benign environment in. 533 01:00:53,380 --> 01:00:58,420 Oh, by the way, all these planets are tidally locked. 534 01:00:59,530 --> 01:01:05,200 That means they have one surface pointing to the sun all the time. 535 01:01:06,380 --> 01:01:10,040 Habitable? Probably not. Probably not. 536 01:01:10,250 --> 01:01:18,340 That's my bet. But here's the important read, the really important element of this discovery. 537 01:01:19,800 --> 01:01:30,480 And that is this star, when it was created, had enough planetarium making material to make seven terrestrial planets. 538 01:01:30,840 --> 01:01:34,000 And it's right around the block. Okay. 539 01:01:35,080 --> 01:01:42,910 And so that tells us we are in an area of the galaxy where we can make terrestrial planets like crazy. 540 01:01:43,780 --> 01:01:54,000 All right. And stars in our initial cluster as we were created from a collapsing cloud in the several hundred stars that were created. 541 01:01:54,390 --> 01:01:59,750 Share all that kind of material. And they're probably littered with planets. 542 01:02:00,860 --> 01:02:05,540 So we are in a perfect place to really study these objects. 543 01:02:06,600 --> 01:02:14,490 Now here's an example of what I'm talking about in terms of the size of this unit relative to our own solar system. 544 01:02:14,700 --> 01:02:24,600 And as you can see, because the star is actually fairly dim, all these planets are really close, but it's an incredibly active star. 545 01:02:25,720 --> 01:02:30,730 So it's an example of some of the things that we've been we've been doing. 546 01:02:30,880 --> 01:02:34,840 Now enters the new mission. TESS Okay. 547 01:02:35,260 --> 01:02:39,280 Tess recently announced that it had gone through. It was launched in April. 548 01:02:39,280 --> 01:02:42,610 It's gone through its commissioning phase and it's starting to find exoplanets. 549 01:02:43,180 --> 01:02:47,140 First one it found already. Here's the light curve from it. 550 01:02:47,890 --> 01:02:53,140 This is a super-Earth. Okay. It's a it's a dwarf yellow star. 551 01:02:54,010 --> 01:02:57,040 Similar problems. It's probably going to be tidally locked. 552 01:02:57,610 --> 01:03:03,970 But it's the start of looking at these this star you can see with your naked eye. 553 01:03:04,540 --> 01:03:08,110 Okay. Tess is looking at all the bright stars. 554 01:03:08,860 --> 01:03:11,830 Bright stars are purposely close to us. 555 01:03:13,220 --> 01:03:23,270 And so as it performs its job over the next couple of years, it's going to be finding a list of fabulous planets, I can guarantee you. 556 01:03:24,140 --> 01:03:29,390 The estimate is it may find as many as a thousand planets over the next couple of years. 557 01:03:29,780 --> 01:03:38,630 Those are going to be candidates for the James Webb Space Telescope to view, tease out what the atmosphere looks like, 558 01:03:38,900 --> 01:03:46,430 and looking for signatures in the atmospheres of these planets to determine if they have life. 559 01:03:48,080 --> 01:03:54,930 So in closing, what a beautiful day was here in Oxford. 560 01:03:54,950 --> 01:04:01,040 It was clear, it was bright, was beautiful. Reminded me of California right now. 561 01:04:02,210 --> 01:04:05,750 So tonight you're actually going to see some stars. 562 01:04:07,400 --> 01:04:10,490 So when you go out tonight, you look up and you see those stars. 563 01:04:11,810 --> 01:04:19,540 I want you to realise. That there are more planets in our galaxy than there are stars. 564 01:04:20,180 --> 01:04:29,460 Okay. And this is a little illustration out of Scientific American a couple of years ago of the known planetary systems in the stars. 565 01:04:30,360 --> 01:04:34,140 And as you can see, planets are everywhere out there. 566 01:04:34,500 --> 01:04:36,990 And with the set of missions that we have lined up, 567 01:04:37,290 --> 01:04:45,240 we're going to interrogate our local area and we're going to hunt down that planet that's most like Earth. 568 01:04:46,180 --> 01:04:51,460 In the in the pursuit of finding life in exoplanets. 569 01:04:52,670 --> 01:05:25,120 Thank you very much. So while we're setting up to pass around a mic and I've got all the people with mikes to give you a meatball, 570 01:05:25,150 --> 01:05:28,150 which is the Nazi symbol, if you ask a question, you get a meatball. 571 01:05:28,780 --> 01:05:36,190 So that's kind of a neat incentive in that. Okay. And I want to hawk my my my podcast. 572 01:05:36,380 --> 01:05:39,760 Okay. So I have a podcast that's called Gravity Assist. 573 01:05:40,730 --> 01:05:45,320 And if you're into podcasts, this is a great way to get caught up with what's going on. 574 01:05:45,330 --> 01:05:54,290 So it's like sitting down with dinner with Jim Green and a scientist, and we talk about the latest things that are going on right now. 575 01:05:54,470 --> 01:06:02,180 We're in the second season. We're talking about some of the spectacular observations all the way from more and more and more movies. 576 01:06:03,020 --> 01:06:10,610 Okay. That's a that's a asteroid that passed through our goal or our solar system that was created in another solar system. 577 01:06:10,880 --> 01:06:13,160 First one we ever found, you know, 578 01:06:13,160 --> 01:06:21,380 all the way to some of the spectacular things that are that Kepler and some of the other telescopes are finding today. 579 01:06:21,950 --> 01:06:26,960 The second the third season that we're going to start here in another month is all on finding life. 580 01:06:27,710 --> 01:06:28,790 It's all on finding life. 581 01:06:28,790 --> 01:06:35,540 So if you want to keep up with what we're doing and it builds on the lecture I the talk I gave today, that's the place to go. 582 01:06:37,480 --> 01:06:41,050 Okay, great. So we're going to take questions in groups of three. 583 01:06:41,470 --> 01:06:44,230 And we've got two people here with roving mikes in the pens. 584 01:06:44,410 --> 01:06:50,710 And they'll just repeat your question when you ask it to make sure that the people watching on the live stream can hear you as well. 585 01:06:57,130 --> 01:07:02,120 I guess we have a first question up there. All right. Great. 586 01:07:15,080 --> 01:07:21,020 I was just wondering, after Mars returns to the habitable zone, have you model? 587 01:07:21,050 --> 01:07:25,220 How long will it take to lose the newly gained atmosphere? 588 01:07:26,720 --> 01:07:33,970 We've started a process, so I'll let me repeat the question. It's really all about Mars coming into a habitable state in the future. 589 01:07:33,980 --> 01:07:37,520 That's what we predict will happen, has all the resources to do it. 590 01:07:38,450 --> 01:07:45,710 We've only started the process of what it would take to keep it there, and there's a whole series of ideas on how to keep it there. 591 01:07:47,810 --> 01:07:52,400 You have to realise for for humans to go to Mars today is really tough. 592 01:07:52,410 --> 01:07:58,580 The environment is really tough, it's very cold, it has huge of temperature cycles. 593 01:07:58,580 --> 01:08:08,540 The pressure is very low. You've got to wear a spacesuit. But if Mars is, atmosphere can build up to ten times what it is today. 594 01:08:09,050 --> 01:08:14,780 So from six millibars to 60 millibars, our atmosphere is 1000 millibars. 595 01:08:14,780 --> 01:08:22,970 Okay. So it doesn't have to go huge amount. Then we can we can get to the point where our blood doesn't boil and that. 596 01:08:23,630 --> 01:08:34,160 Okay. No, I'm just telling you what's happening. And that's a game changer that allows us to have all sorts of capability, mobility, you know, 597 01:08:34,160 --> 01:08:39,380 less infrastructure, the ability to move around and and do a variety of things on Mars. 598 01:08:39,890 --> 01:08:44,870 So there's a lot of talk about how to get it there sooner rather than later. 599 01:08:45,140 --> 01:08:55,100 Wait, wait, wait for the sun to do it. But the concepts of modelling right now at Mars are unbelievable. 600 01:08:55,610 --> 01:09:01,790 We have a global circulation of Mars where we can predict the temperature, the the wind pressure, 601 01:09:01,880 --> 01:09:08,090 the wind velocity and the pressure anywhere on Mars, and watch it evolve over time. 602 01:09:08,480 --> 01:09:15,620 And we've even started to add the dust so we can we actually have got a good representation of of the dust global dust storms to. 603 01:09:16,880 --> 01:09:17,990 And we can do that now. 604 01:09:17,990 --> 01:09:26,370 We are where Nasser and Noel was in predicting the climate on Earth, the weather on Earth in about the late sixties, early seventies. 605 01:09:26,390 --> 01:09:32,310 We're doing that right now at Mars. And we've made enormous progress in that in that particular. 606 01:09:32,320 --> 01:09:35,710 And we need to. So if you saw The Martian, you know why? 607 01:09:36,100 --> 01:09:39,190 You're only kidding. The dust storms aren't anywhere near as bad. 608 01:09:40,390 --> 01:09:46,510 There's a question. Thank you. 609 01:09:47,200 --> 01:09:55,330 Could you summarise the latest thinking on given the right physical conditions, what's the probability that life might evolve? 610 01:09:57,650 --> 01:10:06,430 So to really do a good job of that, we need to understand a few more things about these bodies. 611 01:10:06,440 --> 01:10:10,550 We're not quite sure Europa has all the right stuff, all the right organics. 612 01:10:11,060 --> 01:10:16,970 We believe it does, but we're not quite sure. And that's kind of a game changer in that in that perspective. 613 01:10:17,720 --> 01:10:23,810 But since we don't know what that spark was, we really can't give you a probability. 614 01:10:23,990 --> 01:10:28,130 We have to we have to sort of rely on our our best guess. 615 01:10:28,520 --> 01:10:33,470 Okay. To me, I think it's so that now this is an opinion. 616 01:10:33,800 --> 01:10:40,970 Okay. Take my now some meatball off and just tell you I think the universe is teeming 617 01:10:40,970 --> 01:10:46,700 with life and I think we're going to find it in our solar system first. 618 01:10:47,780 --> 01:10:56,360 And we'll have the opportunity to tease it out, see how it's related to us and make enormous progress in those particular areas. 619 01:10:56,690 --> 01:11:04,170 And we're hot on the pursuit to do that. So in our lifetime, we'll answer the question Are we alone? 620 01:11:06,170 --> 01:11:12,480 Okay. Now I'm going to close the secret files. Close the NSA's secret files. 621 01:11:23,810 --> 01:11:28,610 Thanks for the talk. How good are we at measuring the magnetic fields of these exoplanets? 622 01:11:29,420 --> 01:11:32,780 Yeah. How good are we to measure the magnetic fields of the exoplanets? 623 01:11:33,290 --> 01:11:36,590 We we haven't really started doing that. Okay. 624 01:11:37,070 --> 01:11:46,910 One of the telltale signs of a magnetic field is when that magnetic field interacts with the winds from the stars and produce Aurora. 625 01:11:47,600 --> 01:11:53,950 And above the Aurora is a radio wave that's generated we generated at hours. 626 01:11:53,960 --> 01:12:01,970 It's called a whirl killing metric radiation. And the first radio waves that we saw were coming from Jupiter with that same process. 627 01:12:02,360 --> 01:12:14,690 And those are called DECA metric emissions. So we need to move into the radio regime to look for these radio emissions around these exoplanets. 628 01:12:15,080 --> 01:12:26,300 And so I think as we find them and and as we are able to build bigger and better arrays, we'll be able to will be able to to do that. 629 01:12:26,690 --> 01:12:31,550 Now, they're very frequency dependent. Jupiter has an enormous magnetic field. 630 01:12:32,580 --> 01:12:37,260 And that's why that radiation, the DECA metric radiation, 631 01:12:38,040 --> 01:12:45,990 can be seen from the surface of the earth because of the huge field generates a high frequency radio wave that's in our radio window. 632 01:12:47,860 --> 01:12:56,830 Our Aurora generates a rural killer metric radiation, and that's in the kill metric frequency range, which cannot make it to the surface. 633 01:12:57,280 --> 01:13:00,580 It comes down and gets reflected off the top of the ionosphere. 634 01:13:01,540 --> 01:13:07,929 And so there's a you know, we can only do this in radio windows unless we put a radio telescope on the moon. 635 01:13:07,930 --> 01:13:11,890 And that's being discussed, too, particularly on the far side of the moon. 636 01:13:12,670 --> 01:13:16,240 All right. So there these ideas are coming forth. 637 01:13:16,420 --> 01:13:24,650 You know, we're really thinking about how to do the next steps, but teasing out the magnetic fields would be wonderful. 638 01:13:24,670 --> 01:13:29,470 I would dearly love that. And I'll tell you why. I'm a magnetospheric physicist. 639 01:13:30,670 --> 01:13:32,770 I never met a magnetic field I didn't like, 640 01:13:33,970 --> 01:13:40,150 and I never met a planet that had a magnetic field in the past but didn't have it today that I didn't like either. 641 01:13:40,510 --> 01:13:45,100 So that's about it. That's everything. You know, even our sun has a magnetic field, right? 642 01:13:51,870 --> 01:13:55,140 Hi. Thank you. Oh, you. 643 01:13:56,790 --> 01:14:04,820 I just wanted to ask, what's the state of play or progress of the lunar orbital gateway and to support a human mission to Mars. 644 01:14:04,830 --> 01:14:12,240 And to what degree does the current political situation between the multiple countries involved affect the development of the gateway? 645 01:14:12,960 --> 01:14:20,100 So we've announced a a capability, we're going to put it the moon called the Gateway. 646 01:14:20,820 --> 01:14:30,540 And this is a human tended system, sort of a many, many, many space station, if you will. 647 01:14:31,800 --> 01:14:39,870 And it will be in a what we call Cislunar orbit that has an opportunity to be behind the moon from our 648 01:14:39,870 --> 01:14:48,149 perspective and be able to actually look at the far side of the moon and be available for samples that are found 649 01:14:48,150 --> 01:14:54,540 on the back side of the moon that are brought up to the gateway or from astronauts being able to do tele 650 01:14:54,540 --> 01:15:03,600 robotics to manage and manipulate rovers and get samples and do things in practice of what we will do at Mars. 651 01:15:04,260 --> 01:15:10,049 Because when we land material on Mars, it needs to be built, needs to be put together. 652 01:15:10,050 --> 01:15:14,250 And the first set of things we will probably do will be Tesla robotics. 653 01:15:15,210 --> 01:15:23,470 So we'll need to practice that and do that from an orbital vehicle or we'll land on Phobos and do it from Phobos. 654 01:15:23,490 --> 01:15:27,060 And I've always said Phobos is the space station of Mars, let's use it. 655 01:15:27,720 --> 01:15:30,230 So the gateway is moving along really well. 656 01:15:30,240 --> 01:15:38,040 So what's happened most recently in the last several months are a variety of invitations have gone out to other space agencies to join us. 657 01:15:39,180 --> 01:15:43,740 So we'll we'll see more and more international activity on using the gateway. 658 01:15:45,340 --> 01:15:50,100 And that's one of the frontier that you need a microphone. 659 01:15:53,020 --> 01:15:58,690 So you mentioned the James Webb telescope. That's been delayed several times. 660 01:15:58,900 --> 01:16:01,900 What's the latest prognosis on on that being launched? 661 01:16:01,900 --> 01:16:05,890 Because it'll be an infrared system mounted to the detections. 662 01:16:06,070 --> 01:16:09,280 I am positive James Webb is going to get launched. 663 01:16:09,760 --> 01:16:13,600 Okay. Positive. I'll bet money on it. 664 01:16:13,780 --> 01:16:17,740 Okay. That's how certain I am of the fact that it's delayed. 665 01:16:17,770 --> 01:16:23,740 That's the current situation. But where we are right now, I'm okay with that. 666 01:16:24,310 --> 01:16:28,040 It's got problems. I mean, this is an enormous this is an enormous undertaking. 667 01:16:28,060 --> 01:16:34,500 I mean, it's just it's just unbelievable. And and and we've now wrung out the problems. 668 01:16:34,550 --> 01:16:40,750 We're in the process of fixing those. You know, Isa's going to launch it with an Ariane five. 669 01:16:41,230 --> 01:16:45,100 We're really excited about that. They're going to participate in the program. 670 01:16:46,330 --> 01:16:50,860 While that's happening over the next couple of years, Tess is going to do fantastic things. 671 01:16:51,250 --> 01:16:55,330 Tess is going to line up a set of targets for Webb to look at. 672 01:16:56,200 --> 01:17:03,800 So in a way, it's going to work out and Scott, I think, work out really well because those are the objects we want Webb to look at. 673 01:17:03,820 --> 01:17:08,650 They're close. We'll know a lot about them. And [INAUDIBLE] go right after the atmosphere. 674 01:17:08,830 --> 01:17:12,550 And it's the atmosphere that will tell us whether these bodies are habitable or not. 675 01:17:16,480 --> 01:17:25,040 Timing is everything, I guess. Hi. 676 01:17:25,170 --> 01:17:28,670 You must get, like, hundreds of proposals for different missions every year. 677 01:17:28,700 --> 01:17:35,390 How do you go about selecting which ones to kind of look into and go ahead with and which ones to just put aside? 678 01:17:35,480 --> 01:17:39,139 Yeah. So the question is, we get hundreds of proposals in the year. 679 01:17:39,140 --> 01:17:47,780 How do we how do we make a decision? And that's really pretty easy because we pick the best ones and we execute them. 680 01:17:48,680 --> 01:18:02,300 So we have created the ability to put out a call for proposals to the community that go after certain objectives. 681 01:18:02,810 --> 01:18:11,810 Okay. And for instance, in Planetary, Planetary has a program called Discovery, and that's wide open. 682 01:18:12,530 --> 01:18:21,620 You can you can propose for a discovery mission to go to any planet or solar system body except the sun and the earth. 683 01:18:22,040 --> 01:18:27,229 And, you know, look at create a telescope to look in astrophysics. 684 01:18:27,230 --> 01:18:37,340 It has to be a solar system mission. And that provides a tremendous amount of flexibility for our community to propose against. 685 01:18:38,030 --> 01:18:41,210 And then we have another call that's very targeted. 686 01:18:42,110 --> 01:18:48,180 We have you know, we have a set of targets we're going to go to in the targets are going to be, you know, 687 01:18:48,200 --> 01:19:02,200 comet surface sample return, Europa, you know, Enceladus, you know, Titan and, you know, just array of things that are that are set. 688 01:19:03,440 --> 01:19:07,339 And so we'll get proposals for each of those includes Venus to Venus. 689 01:19:07,340 --> 01:19:12,800 We really would dearly love to have some selectable proposals for Venus, too. 690 01:19:13,400 --> 01:19:20,770 So by by binning them out like that and then also creating what we call strategic missions, 691 01:19:20,770 --> 01:19:28,860 these are the really big ones like Webb is a strategic mission. We then decide, okay, we're going to we're going to spend, you know, a lot of money. 692 01:19:29,340 --> 01:19:33,450 We're going to burn a hole in steel and we're going to do this particular set of science. 693 01:19:33,450 --> 01:19:38,280 And it's going to be expensive when we know that. So we're going to call it a strategic mission. 694 01:19:38,730 --> 01:19:42,930 And then we'll we'll ask investigators to propose four instruments. 695 01:19:43,950 --> 01:19:48,450 This is what Curiosity did. This is what we did for the Mars 2020 rover. 696 01:19:49,050 --> 01:19:54,780 You know, where where we're going to put this rover down on the ground and we need your instruments. 697 01:19:54,910 --> 01:20:05,040 Okay. And then and then we assign we assign a centre in NASA's centre to to be able to to to create that infrastructure. 698 01:20:05,580 --> 01:20:08,790 And for curiosity as an example. That was JPL. 699 01:20:09,510 --> 01:20:16,110 All right. So JPL went through the 7 minutes of terror, just like I did, and we landed it, and it worked great. 700 01:20:17,760 --> 01:20:21,270 And those instruments were from all kinds of places. 701 01:20:21,270 --> 01:20:27,150 And they're and we can do international instruments, too. We have a call that goes out where international partners can come in. 702 01:20:28,380 --> 01:20:35,730 Okay. Okay, great. So any time we're going to move out now to the drinks reception, 703 01:20:36,180 --> 01:20:45,180 I've been asked to let you know that there are some freebies from NASA out there and also a few leaflets from the Worshipful Company. 704 01:20:45,390 --> 01:20:54,770 I'll just hand over to Ian now to close. Not trying to. 705 01:20:58,990 --> 01:21:03,030 You want us to look? It didn't quite close as I expected him to do. 706 01:21:03,030 --> 01:21:07,770 And a couple of things that were to say, yes, the drinks are outside before we actually go outside. 707 01:21:08,190 --> 01:21:15,410 I want you to join me in thanking the speaker, not just because of the incredible material, but also the inspirational way in which he presented a.