1 00:00:29,830 --> 00:00:07,200 [Music] 2 00:00:34,340 --> 00:00:31,880 greetings friends of astrobiology 3 00:00:36,350 --> 00:00:34,350 welcome to a brand new episode of ask an 4 00:00:38,900 --> 00:00:36,360 astrobiologist a show where we celebrate 5 00:00:40,729 --> 00:00:38,910 science and celebrate scientists money 6 00:00:42,380 --> 00:00:40,739 may enjoy some and this program is made 7 00:00:45,470 --> 00:00:42,390 possible by contributions from the NASA 8 00:00:47,660 --> 00:00:45,480 Astrobiology program Elsi the earth Life 9 00:00:49,940 --> 00:00:47,670 Science Institute at Tokyo Tech and the 10 00:00:52,220 --> 00:00:49,950 nonprofit blue Bravo space we're very 11 00:00:54,470 --> 00:00:52,230 excited this months to have a researcher 12 00:00:57,229 --> 00:00:54,480 from France dr. Sean Raymond who is a 13 00:00:59,630 --> 00:00:57,239 astronomer at the ostrov Astrophysical 14 00:01:02,090 --> 00:00:59,640 laboratory in the city of Bordeaux in 15 00:01:03,830 --> 00:01:02,100 France ABS yo attitudes I took the a to 16 00:01:05,780 --> 00:01:03,840 ski to connect the Philip a francophone 17 00:01:08,270 --> 00:01:05,790 EF new a tus you know some a Mojave 18 00:01:10,070 --> 00:01:08,280 deserve our dr. Raymond it's a pleasure 19 00:01:11,780 --> 00:01:10,080 to have you here I know from your 20 00:01:13,760 --> 00:01:11,790 publication record you're so busy 21 00:01:16,300 --> 00:01:13,770 studying all these really cool stuff and 22 00:01:18,350 --> 00:01:16,310 so thanks for being with us today 23 00:01:21,109 --> 00:01:18,360 well thanks a lot it's a pleasure to be 24 00:01:22,789 --> 00:01:21,119 here like we enjoy doing in this show is 25 00:01:25,370 --> 00:01:22,799 before we start talking about the 26 00:01:27,410 --> 00:01:25,380 science is go back in time a little bit 27 00:01:31,280 --> 00:01:27,420 but before we actually talk about that 28 00:01:33,440 --> 00:01:31,290 we had our monthly background quiz that 29 00:01:35,569 --> 00:01:33,450 we need to get started with first so 30 00:01:37,640 --> 00:01:35,579 this month it's a magnificent place on 31 00:01:38,990 --> 00:01:37,650 our solar system that we have the 32 00:01:41,030 --> 00:01:39,000 pleasure of having as a background and 33 00:01:43,639 --> 00:01:41,040 last month it was a different moon in 34 00:01:45,260 --> 00:01:43,649 the solar system that was our background 35 00:01:48,350 --> 00:01:45,270 and the question this month was well 36 00:01:50,330 --> 00:01:48,360 what was that moon and a few of you got 37 00:01:52,310 --> 00:01:50,340 it right um I think only one actually 38 00:01:55,190 --> 00:01:52,320 and that's Adam Robinson shout out to 39 00:01:57,080 --> 00:01:55,200 you good job it was indeed Europa and a 40 00:02:00,649 --> 00:01:57,090 beautiful lynnae's that are on the moon 41 00:02:02,120 --> 00:02:00,659 so next time on the show what is the 42 00:02:06,920 --> 00:02:02,130 planet behind me and I'll give you a 43 00:02:10,430 --> 00:02:06,930 shout outs so was that said Sean if we 44 00:02:13,190 --> 00:02:10,440 go back in time many many years ago in a 45 00:02:13,790 --> 00:02:13,200 galaxy not too far away what caused you 46 00:02:17,180 --> 00:02:13,800 to become a 47 00:02:19,130 --> 00:02:17,190 scientists in the first place I mean I 48 00:02:22,190 --> 00:02:19,140 don't think my story is pretty common 49 00:02:23,720 --> 00:02:22,200 among scientists it was I kind of day 50 00:02:26,300 --> 00:02:23,730 dreamed a lot when I was a kid I read 51 00:02:28,130 --> 00:02:26,310 lots of science fiction books and I was 52 00:02:29,600 --> 00:02:28,140 good at math and so when you put those 53 00:02:31,670 --> 00:02:29,610 things together you naturally gonna 54 00:02:34,940 --> 00:02:31,680 gravitate to what science I got really 55 00:02:37,100 --> 00:02:34,950 into into space stuff in high school 56 00:02:38,690 --> 00:02:37,110 when I started reading all these classic 57 00:02:41,320 --> 00:02:38,700 science fiction stories by people like 58 00:02:44,360 --> 00:02:41,330 Isaac Asimov and arthur c clarke and 59 00:02:46,970 --> 00:02:44,370 from there I mean that was kind of the 60 00:02:48,560 --> 00:02:46,980 seed of my interest in so how did you 61 00:02:50,030 --> 00:02:48,570 develop that interest growing up in high 62 00:02:51,920 --> 00:02:50,040 school and then I know you traveled 63 00:02:54,470 --> 00:02:51,930 quite a bit until your position today 64 00:02:57,830 --> 00:02:54,480 like take us through that path and what 65 00:02:59,540 --> 00:02:57,840 triggered I'd interested in astronomy so 66 00:03:02,120 --> 00:02:59,550 so when I got to college I was 67 00:03:04,460 --> 00:03:02,130 interested in math and science in 68 00:03:06,740 --> 00:03:04,470 general and so I took a bunch of math 69 00:03:08,780 --> 00:03:06,750 classes I took physics and I took 70 00:03:10,100 --> 00:03:08,790 astronomy there was one astronomy class 71 00:03:13,220 --> 00:03:10,110 in the college I went to the small 72 00:03:14,930 --> 00:03:13,230 College in Maine called Bowdoin and so 73 00:03:17,210 --> 00:03:14,940 there's only one astronomy class and I 74 00:03:18,920 --> 00:03:17,220 loved it it was really exciting to me 75 00:03:21,440 --> 00:03:18,930 but there was nowhere to go from there 76 00:03:23,570 --> 00:03:21,450 so so I wasn't sure what to do next and 77 00:03:26,930 --> 00:03:23,580 so what I did is is junior year of 78 00:03:28,400 --> 00:03:26,940 college a lot of my friends didn't there 79 00:03:31,610 --> 00:03:28,410 a semester abroad where they went 80 00:03:34,820 --> 00:03:31,620 and basically partied somewhere you know 81 00:03:36,979 --> 00:03:34,830 they went to they often went to to Spain 82 00:03:39,560 --> 00:03:36,989 or places like that and I did the 83 00:03:40,850 --> 00:03:39,570 opposite I ended up applying to to go to 84 00:03:42,050 --> 00:03:40,860 Caltech for a year to learn about 85 00:03:43,970 --> 00:03:42,060 astronomy because I knew they had good 86 00:03:45,920 --> 00:03:43,980 astronomy there so I went there I 87 00:03:48,170 --> 00:03:45,930 learned a bunch of astronomy it got me 88 00:03:50,420 --> 00:03:48,180 even more excited about it then I 89 00:03:52,190 --> 00:03:50,430 applied to grad so I went to Seattle to 90 00:03:55,310 --> 00:03:52,200 do astronomy and then it kind of just 91 00:03:57,620 --> 00:03:55,320 went from there and then you moved out 92 00:03:59,870 --> 00:03:57,630 of the United States to start a research 93 00:04:01,820 --> 00:03:59,880 career in France how is that transition 94 00:04:03,680 --> 00:04:01,830 is it easy to do and I know as a postdoc 95 00:04:06,080 --> 00:04:03,690 you had a kid - so you changing 96 00:04:08,660 --> 00:04:06,090 countries having kid how did you get 97 00:04:11,290 --> 00:04:08,670 that keep going that's awesome so so 98 00:04:15,259 --> 00:04:11,300 grad school I was in Seattle then I 99 00:04:18,890 --> 00:04:15,269 actually had a an unusual experience for 100 00:04:21,170 --> 00:04:18,900 for being a postdoc - so I when I by the 101 00:04:22,850 --> 00:04:21,180 time I finished my thesis my wife had 102 00:04:25,400 --> 00:04:22,860 already started a program in genic 103 00:04:27,270 --> 00:04:25,410 counseling in Denver and so I only 104 00:04:29,670 --> 00:04:27,280 applied for jobs there 105 00:04:31,860 --> 00:04:29,680 and I didn't get any and so I was stuck 106 00:04:33,360 --> 00:04:31,870 I had no job for several months I got 107 00:04:35,340 --> 00:04:33,370 really bummed out I was getting close to 108 00:04:39,030 --> 00:04:35,350 applying to you know REI or places like 109 00:04:41,270 --> 00:04:39,040 this I didn't quite come to that I ended 110 00:04:44,220 --> 00:04:41,280 up getting rescued by Vicky Meadows of 111 00:04:46,290 --> 00:04:44,230 virtual planetary laboratory Fame who 112 00:04:48,600 --> 00:04:46,300 hired me to work for her for a year 113 00:04:50,670 --> 00:04:48,610 until I got this other fellowship - to 114 00:04:52,830 --> 00:04:50,680 keep things going and so yeah while I 115 00:04:55,770 --> 00:04:52,840 was in Colorado as a postdoc I had a kid 116 00:04:58,890 --> 00:04:55,780 we had a our son Owen who just turned 10 117 00:05:01,920 --> 00:04:58,900 now and while we were in Colorado I also 118 00:05:04,260 --> 00:05:01,930 was invited out to France to basically 119 00:05:06,210 --> 00:05:04,270 as a sabbatical sort of when I was still 120 00:05:07,980 --> 00:05:06,220 a postdoc which is really cool so I came 121 00:05:10,140 --> 00:05:07,990 to Bordeaux then and stayed for about 122 00:05:12,900 --> 00:05:10,150 three months met a lot of people and 123 00:05:15,420 --> 00:05:12,910 they they kind of persuaded me to apply 124 00:05:16,770 --> 00:05:15,430 for a permanent job here and I was kind 125 00:05:19,110 --> 00:05:16,780 of nervous about it and they persuaded 126 00:05:20,280 --> 00:05:19,120 me to apply by saying hi you know that 127 00:05:22,560 --> 00:05:20,290 you probably won't get it usually had to 128 00:05:24,930 --> 00:05:22,570 apply many years in a row so if you 129 00:05:26,280 --> 00:05:24,940 apply now then maybe in 2 3 4 years 130 00:05:28,320 --> 00:05:26,290 you'll be in a good position to get the 131 00:05:30,210 --> 00:05:28,330 job but then somehow I was in the right 132 00:05:32,790 --> 00:05:30,220 place at the right time and I got the 133 00:05:35,400 --> 00:05:32,800 job the first time and and we came here 134 00:05:38,219 --> 00:05:35,410 and the rest is history like they say 135 00:05:40,050 --> 00:05:38,229 you mentioned Vicky Meadows she's been a 136 00:05:42,870 --> 00:05:40,060 mentor for many of us early careers in 137 00:05:45,480 --> 00:05:42,880 astrobiology over the years is he and is 138 00:05:47,820 --> 00:05:45,490 there any other people that you looked 139 00:05:51,450 --> 00:05:47,830 up to growing up as a scientist that 140 00:05:54,090 --> 00:05:51,460 helped you along the way so so yeah if I 141 00:05:55,290 --> 00:05:54,100 was gonna I can think of two people that 142 00:05:57,659 --> 00:05:55,300 I would consider kind of mentors 143 00:05:59,640 --> 00:05:57,669 starting saying grad school - no and one 144 00:06:02,280 --> 00:05:59,650 of them is Vicky meadows she helped me 145 00:06:05,219 --> 00:06:02,290 out a lot in many different ways and the 146 00:06:07,409 --> 00:06:05,229 other one is Susanne Holly professor at 147 00:06:09,420 --> 00:06:07,419 University of Washington she was kind of 148 00:06:11,250 --> 00:06:09,430 a mentor to half the grad students I 149 00:06:12,870 --> 00:06:11,260 think she organized some she played 150 00:06:15,000 --> 00:06:12,880 sports with us play basketball and 151 00:06:17,640 --> 00:06:15,010 softball with us she had us over to her 152 00:06:19,620 --> 00:06:17,650 house to Beatson and drink beer and gave 153 00:06:21,600 --> 00:06:19,630 us like kind of specific advice on how 154 00:06:23,969 --> 00:06:21,610 to approach different problems that came 155 00:06:25,590 --> 00:06:23,979 up it was really helpful so so those are 156 00:06:27,990 --> 00:06:25,600 kind of the two key people they helped 157 00:06:29,370 --> 00:06:28,000 me out I think that's a common story for 158 00:06:31,110 --> 00:06:29,380 all of us or scientists or really 159 00:06:33,090 --> 00:06:31,120 benefit from mentoring to develop this 160 00:06:34,920 --> 00:06:33,100 career so all of you who are watching 161 00:06:36,450 --> 00:06:34,930 who want to become scientists make sure 162 00:06:38,159 --> 00:06:36,460 you connect with good mentors you know 163 00:06:40,980 --> 00:06:38,169 that's important and we all done it and 164 00:06:42,210 --> 00:06:40,990 that's it's makes life a lot easier 165 00:06:43,140 --> 00:06:42,220 so since you've been in Bordeaux you've 166 00:06:45,120 --> 00:06:43,150 been studying some really incredible 167 00:06:47,700 --> 00:06:45,130 stuff I was mentioning the history of 168 00:06:50,219 --> 00:06:47,710 water on earth you were actually on the 169 00:06:52,050 --> 00:06:50,229 paper that announced the discovery of 170 00:06:53,520 --> 00:06:52,060 those the seven planet system the 171 00:06:55,740 --> 00:06:53,530 Trappist system a couple of months ago 172 00:06:57,540 --> 00:06:55,750 which is fantastic and you also you 173 00:07:00,110 --> 00:06:57,550 simulates different types of solar 174 00:07:02,040 --> 00:07:00,120 system so we can talk forever so perhaps 175 00:07:04,200 --> 00:07:02,050 let's or was the beginning I know you 176 00:07:05,730 --> 00:07:04,210 research to begin with for your very 177 00:07:07,230 --> 00:07:05,740 doctorate was around the history of 178 00:07:11,430 --> 00:07:07,240 water on Earth 179 00:07:14,189 --> 00:07:11,440 well what did our oceans come from so 180 00:07:15,719 --> 00:07:14,199 that's a big question so it's really 181 00:07:17,610 --> 00:07:15,729 interesting though because based on 182 00:07:20,580 --> 00:07:17,620 everything that we think we know about 183 00:07:22,980 --> 00:07:20,590 how planets form all the building blocks 184 00:07:25,800 --> 00:07:22,990 of the earth at least around where earth 185 00:07:27,990 --> 00:07:25,810 is now around orbits close to us should 186 00:07:30,089 --> 00:07:28,000 have been dry so we know that the 187 00:07:31,920 --> 00:07:30,099 mystery is weird and earth gets water 188 00:07:34,320 --> 00:07:31,930 from them and so we think it had to be 189 00:07:35,820 --> 00:07:34,330 delivered from somewhere colder from 190 00:07:37,860 --> 00:07:35,830 somewhere further away from the Sun 191 00:07:40,529 --> 00:07:37,870 where the conditions were such that yet 192 00:07:44,670 --> 00:07:40,539 ice and they you know that could 193 00:07:47,670 --> 00:07:44,680 condense somehow the icy icy bodies 194 00:07:50,249 --> 00:07:47,680 maybe icy asteroids or comets bashed 195 00:07:51,839 --> 00:07:50,259 into the earth as it was grown and so it 196 00:07:53,640 --> 00:07:51,849 used to be thought that the earth formed 197 00:07:56,399 --> 00:07:53,650 dry then there was this big kind of 198 00:07:59,610 --> 00:07:56,409 deluge of comets that delivered the 199 00:08:02,879 --> 00:07:59,620 water and that was the state of the art 200 00:08:05,550 --> 00:08:02,889 around year 2000 or so and that's when 201 00:08:06,959 --> 00:08:05,560 things started to change and then it it 202 00:08:09,540 --> 00:08:06,969 switched from thinking that it was 203 00:08:11,490 --> 00:08:09,550 mostly comets to mostly asteroids and 204 00:08:13,499 --> 00:08:11,500 the reason for that is that the chemical 205 00:08:15,899 --> 00:08:13,509 signature of water and comets is 206 00:08:17,279 --> 00:08:15,909 different than in asteroids and the one 207 00:08:19,620 --> 00:08:17,289 asteroids basically it's kind of 208 00:08:21,689 --> 00:08:19,630 asteroids called sea types that are 209 00:08:23,580 --> 00:08:21,699 linked with carbonaceous chondrite 210 00:08:25,890 --> 00:08:23,590 meteorites so we have pieces of them and 211 00:08:27,330 --> 00:08:25,900 we can measure the water in these sea 212 00:08:30,089 --> 00:08:27,340 types these carbonaceous meteorites 213 00:08:32,399 --> 00:08:30,099 looks like water on earth and so then we 214 00:08:34,079 --> 00:08:32,409 thought that it was just kind of a you 215 00:08:36,510 --> 00:08:34,089 know that the earth formed mostly from 216 00:08:38,699 --> 00:08:36,520 stuff nearby but as it was forming some 217 00:08:40,560 --> 00:08:38,709 little fraction of that originated 218 00:08:43,350 --> 00:08:40,570 further out out and what's now the 219 00:08:45,210 --> 00:08:43,360 asteroid belt of course then the story 220 00:08:47,310 --> 00:08:45,220 kept getting more and more complicated 221 00:08:49,439 --> 00:08:47,320 because those models that did great like 222 00:08:51,569 --> 00:08:49,449 getting water on earth didn't match 223 00:08:52,710 --> 00:08:51,579 other parts of the solar system so we've 224 00:08:54,130 --> 00:08:52,720 been spending a lot of time trying to 225 00:08:55,360 --> 00:08:54,140 you know have a model 226 00:08:57,640 --> 00:08:55,370 that can reproduce the whole solar 227 00:08:59,500 --> 00:08:57,650 system and it doesn't you know it's 228 00:09:01,690 --> 00:08:59,510 great to understand where water on earth 229 00:09:03,610 --> 00:09:01,700 came from that's only one piece of this 230 00:09:05,050 --> 00:09:03,620 big puzzle and you gotta get all the 231 00:09:07,510 --> 00:09:05,060 pieces to fit otherwise it doesn't work 232 00:09:08,860 --> 00:09:07,520 and so so since then the story's evolved 233 00:09:11,470 --> 00:09:08,870 there's new models for how the solar 234 00:09:12,820 --> 00:09:11,480 system may have formed and going along 235 00:09:15,250 --> 00:09:12,830 with each model there's different 236 00:09:17,710 --> 00:09:15,260 mechanisms for how because water it's 237 00:09:19,600 --> 00:09:17,720 tough somehow got close to the soul you 238 00:09:21,340 --> 00:09:19,610 know closer to the Sun and bashed into 239 00:09:23,170 --> 00:09:21,350 the earth as a group and right now the 240 00:09:25,960 --> 00:09:23,180 latest thinking is that Jupiter played a 241 00:09:28,240 --> 00:09:25,970 key role just by growing does Jupiter 242 00:09:30,160 --> 00:09:28,250 growing toss is a bunch of nearby stuff 243 00:09:31,270 --> 00:09:30,170 all over the place that stuff should 244 00:09:33,030 --> 00:09:31,280 probably have had a decent amount of 245 00:09:35,080 --> 00:09:33,040 water and some of the bashing of years 246 00:09:36,610 --> 00:09:35,090 sorry that was probably longer answer 247 00:09:39,190 --> 00:09:36,620 than you were expected but no it's 248 00:09:41,770 --> 00:09:39,200 really interesting this is really 249 00:09:43,480 --> 00:09:41,780 interesting because it does perhaps play 250 00:09:45,280 --> 00:09:43,490 into a role in thinking about life on 251 00:09:47,920 --> 00:09:45,290 other worlds if life does indeed depend 252 00:09:49,900 --> 00:09:47,930 on water and earth is in the right 253 00:09:51,940 --> 00:09:49,910 habitable zone of the star not too far 254 00:09:54,490 --> 00:09:51,950 not too close and yet you also need a 255 00:09:56,260 --> 00:09:54,500 giant planet far away to kind of send 256 00:09:58,810 --> 00:09:56,270 all the material into the inner solar 257 00:10:01,120 --> 00:09:58,820 system to see the planet with water for 258 00:10:03,550 --> 00:10:01,130 example that does does that mean that 259 00:10:05,860 --> 00:10:03,560 you know for our life to evolve on a 260 00:10:10,300 --> 00:10:05,870 planet doesn't need a large jupiter-like 261 00:10:13,360 --> 00:10:10,310 planet outside of it so that's a good 262 00:10:15,790 --> 00:10:13,370 question so the question that you asked 263 00:10:17,950 --> 00:10:15,800 me and the most people asked is you know 264 00:10:20,740 --> 00:10:17,960 it's basically and also the way I framed 265 00:10:24,910 --> 00:10:20,750 the answer is why is Earth so what right 266 00:10:26,620 --> 00:10:24,920 why do we have water at all but another 267 00:10:28,720 --> 00:10:26,630 question and these days we're kind of 268 00:10:31,450 --> 00:10:28,730 flipping other things around is why is 269 00:10:33,700 --> 00:10:31,460 Earth so dry but he's done how we think 270 00:10:37,780 --> 00:10:33,710 these things form it's really hard to 271 00:10:40,270 --> 00:10:37,790 prevent things from getting from water 272 00:10:44,110 --> 00:10:40,280 rich bodies coming into the inner solar 273 00:10:46,570 --> 00:10:44,120 system and so it's possible that we 274 00:10:48,400 --> 00:10:46,580 think a Jupiter played a key role you 275 00:10:50,140 --> 00:10:48,410 know it did as it grew we think it's 276 00:10:51,820 --> 00:10:50,150 sprinkled some water it's stuff onto the 277 00:10:54,070 --> 00:10:51,830 earth and got the water that we have 278 00:10:55,360 --> 00:10:54,080 onto there but it's possible that it 279 00:10:57,700 --> 00:10:55,370 played another role in terms of 280 00:11:00,550 --> 00:10:57,710 protecting the inner solar system from 281 00:11:02,590 --> 00:11:00,560 what was beyond Jupiter and so we think 282 00:11:04,600 --> 00:11:02,600 that as planets grow you know they grow 283 00:11:07,670 --> 00:11:04,610 in these big discs of gas and dust 284 00:11:10,430 --> 00:11:07,680 around young stars and as they grow 285 00:11:13,250 --> 00:11:10,440 tend to launch density waves in the gas 286 00:11:15,410 --> 00:11:13,260 once say once a once an object is about 287 00:11:17,180 --> 00:11:15,420 the size of the earth or so and so we're 288 00:11:19,639 --> 00:11:17,190 talking more you know things that are 289 00:11:21,740 --> 00:11:19,649 like the cores of the giant planets or 290 00:11:24,500 --> 00:11:21,750 Uranus Neptune saturn those things not 291 00:11:26,030 --> 00:11:24,510 the growing earth so further out those 292 00:11:28,160 --> 00:11:26,040 things launch density ways and that 293 00:11:31,930 --> 00:11:28,170 tends to change their orbits it tends to 294 00:11:34,550 --> 00:11:31,940 make a move inward and what we think is 295 00:11:36,980 --> 00:11:34,560 Jupiter's role may not have been so much 296 00:11:38,780 --> 00:11:36,990 to but just the right amount of water on 297 00:11:41,210 --> 00:11:38,790 earth but it may have been even more 298 00:11:44,000 --> 00:11:41,220 important that it blocked the inward 299 00:11:47,329 --> 00:11:44,010 migration of these bodies and so we see 300 00:11:49,310 --> 00:11:47,339 planets that you know that are very 301 00:11:51,560 --> 00:11:49,320 close to their stars so-called 302 00:11:53,750 --> 00:11:51,570 super-earth planets they exist around 303 00:11:55,030 --> 00:11:53,760 half of all stars all right they're 304 00:11:57,560 --> 00:11:55,040 super common they're all over the place 305 00:11:59,990 --> 00:11:57,570 one model for how they got there is that 306 00:12:02,000 --> 00:12:00,000 they've started off you know farther out 307 00:12:04,100 --> 00:12:02,010 like like you're innocent Neptune or 308 00:12:06,370 --> 00:12:04,110 Saturn and then they migrated inward and 309 00:12:08,750 --> 00:12:06,380 end up really close to their stars and 310 00:12:10,310 --> 00:12:08,760 so Jupiter's role may have been to 311 00:12:13,340 --> 00:12:10,320 basically block that migration and 312 00:12:15,740 --> 00:12:13,350 protect the growing rocky planets from 313 00:12:17,600 --> 00:12:15,750 those invaders so so again it's another 314 00:12:19,970 --> 00:12:17,610 idea that's out there but it's 315 00:12:22,070 --> 00:12:19,980 fascinating so that means that the 316 00:12:25,280 --> 00:12:22,080 location where the planets are in our 317 00:12:28,699 --> 00:12:25,290 current solar system has changed over 318 00:12:30,560 --> 00:12:28,709 time is it still changing so they 319 00:12:33,500 --> 00:12:30,570 definitely changed over time it's not 320 00:12:35,720 --> 00:12:33,510 changing much now not the planets orbits 321 00:12:37,760 --> 00:12:35,730 are their orbital distances are more or 322 00:12:40,190 --> 00:12:37,770 less fixed and so they evolve and they 323 00:12:41,449 --> 00:12:40,200 exchange angular momentum by kicking 324 00:12:44,449 --> 00:12:41,459 each other a little bit here and there 325 00:12:47,110 --> 00:12:44,459 but there's not much chance of a big 326 00:12:49,579 --> 00:12:47,120 change in the future between now and 327 00:12:51,410 --> 00:12:49,589 when the Sun becomes a red giant in a 328 00:12:53,960 --> 00:12:51,420 you know five billion years there's 329 00:12:55,250 --> 00:12:53,970 something like a 1% chance that the 330 00:12:57,710 --> 00:12:55,260 terrestrial planet system will go 331 00:12:59,690 --> 00:12:57,720 unstable and you know there'll be a 332 00:13:01,100 --> 00:12:59,700 collision between planets this is 333 00:13:03,350 --> 00:13:01,110 actually this punch guy is less gosh 334 00:13:05,449 --> 00:13:03,360 there were this really nice thing so 335 00:13:07,670 --> 00:13:05,459 that that's possible but unlikely 336 00:13:09,380 --> 00:13:07,680 so much more likely is just that our 337 00:13:11,449 --> 00:13:09,390 orbits will be stable they're still 338 00:13:13,190 --> 00:13:11,459 chaotic you can't predict what they'll 339 00:13:15,410 --> 00:13:13,200 you know what they'll do and you know 340 00:13:18,470 --> 00:13:15,420 indefinitely into the future but they're 341 00:13:20,360 --> 00:13:18,480 unlikely to go unstable for those of you 342 00:13:21,600 --> 00:13:20,370 who are sci-fi writer as you're welcome 343 00:13:23,910 --> 00:13:21,610 for the amazing material 344 00:13:25,380 --> 00:13:23,920 just talked about so let's talk about 345 00:13:27,300 --> 00:13:25,390 the solar systems a bit more that's 346 00:13:29,519 --> 00:13:27,310 something you simulates in a computer is 347 00:13:31,530 --> 00:13:29,529 try to predict what kind of planetary 348 00:13:34,139 --> 00:13:31,540 configurations could be stable around 349 00:13:36,060 --> 00:13:34,149 different kind of stars how special how 350 00:13:37,949 --> 00:13:36,070 unique is our solar system do with you 351 00:13:40,500 --> 00:13:37,959 would we expect it elsewhere what other 352 00:13:44,639 --> 00:13:40,510 stable planetary configurations have you 353 00:13:46,560 --> 00:13:44,649 found that's a big question so so 354 00:13:47,850 --> 00:13:46,570 there's there's two kinds of ways to 355 00:13:50,250 --> 00:13:47,860 answer I can either answer from the 356 00:13:53,100 --> 00:13:50,260 point of view of observations of what we 357 00:13:54,509 --> 00:13:53,110 know empirically or from what comes out 358 00:13:57,690 --> 00:13:54,519 of the computer so let me do the 359 00:13:59,490 --> 00:13:57,700 observations part first so so take the 360 00:14:01,620 --> 00:13:59,500 solar system and put it around another 361 00:14:04,680 --> 00:14:01,630 star and then let's observe it with our 362 00:14:07,230 --> 00:14:04,690 current Earth technology what could we 363 00:14:09,389 --> 00:14:07,240 see we have eight planets the only one 364 00:14:11,130 --> 00:14:09,399 that we can find is Jupiter so if we're 365 00:14:12,300 --> 00:14:11,140 trying to figure out how common solar 366 00:14:15,660 --> 00:14:12,310 systems are what we're really looking 367 00:14:17,910 --> 00:14:15,670 for our Sun Jupiter systems and so based 368 00:14:19,170 --> 00:14:17,920 on just the orbit of Jupiter you know 369 00:14:20,639 --> 00:14:19,180 well it was stupid we know Jupiter's 370 00:14:22,319 --> 00:14:20,649 mass well we can measure stupider is 371 00:14:24,930 --> 00:14:22,329 mass and kind of its orbital distance 372 00:14:26,189 --> 00:14:24,940 and its orbital shape and if you put 373 00:14:28,079 --> 00:14:26,199 those three things together what 374 00:14:31,949 --> 00:14:28,089 fraction of stars like the Sun have that 375 00:14:33,990 --> 00:14:31,959 it's about one percent it's about 10% of 376 00:14:35,939 --> 00:14:34,000 stars have a planet of Jupiter's mass 377 00:14:37,680 --> 00:14:35,949 and about ten percent of those have 378 00:14:40,259 --> 00:14:37,690 orbits you know broadly similar to 379 00:14:43,110 --> 00:14:40,269 Jupiter's so we don't know how common 380 00:14:45,509 --> 00:14:43,120 solar systems are overall but they can't 381 00:14:47,310 --> 00:14:45,519 be more common than one percent because 382 00:14:49,829 --> 00:14:47,320 we know that all we can see is is that 383 00:14:51,930 --> 00:14:49,839 so it's possible that Earth's are more 384 00:14:54,780 --> 00:14:51,940 common than that but solar systems can't 385 00:14:57,990 --> 00:14:54,790 be more common if they're interesting 386 00:15:00,030 --> 00:14:58,000 interesting yeah that's great if any of 387 00:15:02,970 --> 00:15:00,040 you who are watching have questions for 388 00:15:05,699 --> 00:15:02,980 dr. Raymond please use hashtag ask ask 389 00:15:07,050 --> 00:15:05,709 for bio on Twitter or if you are on say 390 00:15:08,220 --> 00:15:07,060 Gannett type into the chat room for 391 00:15:11,400 --> 00:15:08,230 those of you who are connecting on 392 00:15:13,079 --> 00:15:11,410 Facebook live yeah I think ask questions 393 00:15:16,050 --> 00:15:13,089 there too we'll be monitoring monitoring 394 00:15:18,000 --> 00:15:16,060 of those so Shawn you've been working on 395 00:15:20,790 --> 00:15:18,010 these exoplanets and habitability of 396 00:15:22,650 --> 00:15:20,800 these of these of these other worlds and 397 00:15:24,269 --> 00:15:22,660 you've been on the paper of the Trappist 398 00:15:25,829 --> 00:15:24,279 system could you remind us what Trappist 399 00:15:27,990 --> 00:15:25,839 is how do you got involved and what does 400 00:15:32,370 --> 00:15:28,000 that possibly mean as a observational 401 00:15:34,319 --> 00:15:32,380 target so that I mean so Trappist one is 402 00:15:34,960 --> 00:15:34,329 it's one of the coolest planetary 403 00:15:37,540 --> 00:15:34,970 systems that's 404 00:15:39,369 --> 00:15:37,550 found today so the star itself is this 405 00:15:42,429 --> 00:15:39,379 puny little starts barely a star tool 406 00:15:44,920 --> 00:15:42,439 just barely above the brown dwarf star 407 00:15:46,660 --> 00:15:44,930 boundary so it's it's only about eight 408 00:15:49,420 --> 00:15:46,670 percent the mass of the Sun it's really 409 00:15:52,210 --> 00:15:49,430 faint but it has a system of seven known 410 00:15:54,389 --> 00:15:52,220 planets that are all on very compact 411 00:15:56,740 --> 00:15:54,399 orbits and since this thing is so faint 412 00:15:58,990 --> 00:15:56,750 these orbits that are so close to the 413 00:16:00,429 --> 00:15:59,000 star are in you know several them are in 414 00:16:04,569 --> 00:16:00,439 the habitable zone which is pretty cool 415 00:16:07,689 --> 00:16:04,579 and so they're all all seven are broadly 416 00:16:08,889 --> 00:16:07,699 earth sized and within a factor of you 417 00:16:12,069 --> 00:16:08,899 know thirty percent of something like 418 00:16:13,800 --> 00:16:12,079 that of the size of the earth and to me 419 00:16:16,269 --> 00:16:13,810 with the coolest part of all is that 420 00:16:16,929 --> 00:16:16,279 their orbital configuration is very 421 00:16:20,499 --> 00:16:16,939 special 422 00:16:22,869 --> 00:16:20,509 their each pair of planets is in what we 423 00:16:24,579 --> 00:16:22,879 call an orbital resonance so they go 424 00:16:28,090 --> 00:16:24,589 around and kind of integer multiple 425 00:16:29,590 --> 00:16:28,100 times each other so for example a couple 426 00:16:30,910 --> 00:16:29,600 of them are in three to two residents 427 00:16:33,879 --> 00:16:30,920 that means that the inner planet goes 428 00:16:36,670 --> 00:16:33,889 around three times for every two orbits 429 00:16:39,910 --> 00:16:36,680 of the outer world and the whole seven 430 00:16:42,460 --> 00:16:39,920 planet system is in a giant resonant 431 00:16:48,610 --> 00:16:42,470 chain which is really cool it's a really 432 00:16:50,889 --> 00:16:48,620 nice setup and it's perfectly stable if 433 00:16:52,269 --> 00:16:50,899 you take into account that the planets 434 00:16:54,299 --> 00:16:52,279 didn't just kind of form there by chance 435 00:16:59,410 --> 00:16:54,309 by bashing into each other they probably 436 00:17:01,119 --> 00:16:59,420 migrated inward Jupiter protecting the 437 00:17:03,340 --> 00:17:01,129 inner solar system from things migrating 438 00:17:05,679 --> 00:17:03,350 inward this is an example it's pretty 439 00:17:06,970 --> 00:17:05,689 clear these planets did migrate at least 440 00:17:09,850 --> 00:17:06,980 to some degree to end up in that 441 00:17:12,059 --> 00:17:09,860 configuration so so that's the system 442 00:17:13,929 --> 00:17:12,069 and I played a very small role in 443 00:17:16,179 --> 00:17:13,939 discovering but it was really fun and 444 00:17:18,549 --> 00:17:16,189 exciting I was really happy to be part I 445 00:17:21,039 --> 00:17:18,559 was contacted me and and another guy 446 00:17:24,399 --> 00:17:21,049 says he's in Bordeaux we were contacted 447 00:17:26,140 --> 00:17:24,409 I guess a couple years ago now after 448 00:17:29,799 --> 00:17:26,150 they had found three planets around 449 00:17:33,159 --> 00:17:29,809 Travis one and the third of those 450 00:17:35,230 --> 00:17:33,169 planets looked weird so they only had a 451 00:17:37,930 --> 00:17:35,240 few different transits they had seen and 452 00:17:39,520 --> 00:17:37,940 at least in two cases the transits were 453 00:17:41,049 --> 00:17:39,530 double it looked like there were two 454 00:17:44,649 --> 00:17:41,059 planets crossing in front of the star at 455 00:17:46,480 --> 00:17:44,659 the same time and this means something's 456 00:17:48,740 --> 00:17:46,490 you know something's going on because 457 00:17:50,180 --> 00:17:48,750 the odds of seeing two planets at once 458 00:17:53,360 --> 00:17:50,190 right as they're passing in front of a 459 00:17:55,580 --> 00:17:53,370 star very small so what they thought the 460 00:17:57,740 --> 00:17:55,590 you know because you know the main guy 461 00:17:59,720 --> 00:17:57,750 and I'm oh hey Tia what they thought at 462 00:18:02,149 --> 00:17:59,730 the time was it was it possible that 463 00:18:04,519 --> 00:18:02,159 this was actually a binary planet so a 464 00:18:07,580 --> 00:18:04,529 planet you know instead of an Earth Moon 465 00:18:10,519 --> 00:18:07,590 system like an earth Earth system in 466 00:18:12,139 --> 00:18:10,529 orbit around the star and they asked me 467 00:18:13,759 --> 00:18:12,149 and Punk and then another guy said I 468 00:18:15,649 --> 00:18:13,769 mean a cone to kind of think about this 469 00:18:18,470 --> 00:18:15,659 you know would this be possible could 470 00:18:19,940 --> 00:18:18,480 this ever form would it be stable you 471 00:18:22,009 --> 00:18:19,950 know what would it look like if we were 472 00:18:23,840 --> 00:18:22,019 measuring it and so we started thinking 473 00:18:25,789 --> 00:18:23,850 about that in the meantime they got more 474 00:18:28,730 --> 00:18:25,799 observations and they found that there 475 00:18:31,789 --> 00:18:28,740 was this long resonant chain and so then 476 00:18:33,350 --> 00:18:31,799 the explanation for why they saw double 477 00:18:35,899 --> 00:18:33,360 transits was because of the resonance is 478 00:18:37,940 --> 00:18:35,909 not and not because it was a binary but 479 00:18:40,940 --> 00:18:37,950 it was still exciting it was fun to be 480 00:18:44,180 --> 00:18:40,950 Barba's yeah fascinating fascinating 481 00:18:46,159 --> 00:18:44,190 so the James Webb Space Telescope should 482 00:18:48,499 --> 00:18:46,169 be launching towards the end of this 483 00:18:51,369 --> 00:18:48,509 year and the Trappist system is not 484 00:18:53,539 --> 00:18:51,379 particularly far astronomically speaking 485 00:18:55,789 --> 00:18:53,549 what do you think we will learn new 486 00:19:01,070 --> 00:18:55,799 about this system if we have a point to 487 00:19:03,049 --> 00:19:01,080 it was there was a James Webb I this is 488 00:19:05,690 --> 00:19:03,059 a that's a good question I don't know 489 00:19:07,460 --> 00:19:05,700 the answer to that I asked people about 490 00:19:11,060 --> 00:19:07,470 this kind of thing a lot exactly what 491 00:19:13,519 --> 00:19:11,070 can be nailed down from observations and 492 00:19:15,769 --> 00:19:13,529 it's very I mean planets are complicated 493 00:19:18,320 --> 00:19:15,779 and so exactly what is gonna come out I 494 00:19:20,600 --> 00:19:18,330 can't predict I don't know I think it's 495 00:19:22,730 --> 00:19:20,610 always worth going and looking because 496 00:19:25,009 --> 00:19:22,740 you can never it's great to come up with 497 00:19:27,350 --> 00:19:25,019 as many crazy ideas as you possibly can 498 00:19:29,299 --> 00:19:27,360 there's any gotta test them so I don't 499 00:19:30,919 --> 00:19:29,309 think it's worth you know thinking that 500 00:19:32,180 --> 00:19:30,929 we know it's coming in advance it's 501 00:19:34,970 --> 00:19:32,190 worth going and looking and seeing and 502 00:19:37,430 --> 00:19:34,980 we don't have wisdom about what you may 503 00:19:39,200 --> 00:19:37,440 found do we know if these planets have 504 00:19:42,980 --> 00:19:39,210 atmospheres because that was fears tend 505 00:19:45,560 --> 00:19:42,990 to hold the signatures of life it would 506 00:19:47,840 --> 00:19:45,570 be awesome if they do I mean I think 507 00:19:49,430 --> 00:19:47,850 given that there that they migrated 508 00:19:52,759 --> 00:19:49,440 clearly they migrated at least to some 509 00:19:54,289 --> 00:19:52,769 degree that means that they must have 510 00:19:55,850 --> 00:19:54,299 started off a little bit further out 511 00:19:58,730 --> 00:19:55,860 than they are now right now the 512 00:20:00,499 --> 00:19:58,740 outermost ones are the outermost couple 513 00:20:01,810 --> 00:20:00,509 couple planets are near even a little 514 00:20:04,090 --> 00:20:01,820 bit past 515 00:20:07,870 --> 00:20:04,100 would call the snow line the snow line 516 00:20:11,200 --> 00:20:07,880 is is the distance from the star beyond 517 00:20:12,670 --> 00:20:11,210 which ice can condense so inside the 518 00:20:14,380 --> 00:20:12,680 snow line you can build plants out of 519 00:20:16,630 --> 00:20:14,390 rocks past the snow line you can build 520 00:20:18,010 --> 00:20:16,640 plants out of rocks and water so you 521 00:20:20,260 --> 00:20:18,020 expect things to be much more water rich 522 00:20:22,360 --> 00:20:20,270 past there so at least the outermost one 523 00:20:23,740 --> 00:20:22,370 or two planets this probably has a 524 00:20:26,110 --> 00:20:23,750 decent amount of water just from where 525 00:20:27,730 --> 00:20:26,120 it is now and if the other ones migrate 526 00:20:29,980 --> 00:20:27,740 inward it's possible that they all have 527 00:20:31,510 --> 00:20:29,990 a decent amount of water and if they 528 00:20:32,830 --> 00:20:31,520 have water then they probably have all 529 00:20:35,650 --> 00:20:32,840 the other volatiles that can contribute 530 00:20:37,390 --> 00:20:35,660 to an atmosphere so so this is kind of 531 00:20:38,890 --> 00:20:37,400 you know a line of thinking that would 532 00:20:41,680 --> 00:20:38,900 argue they probably have atmospheres but 533 00:20:43,060 --> 00:20:41,690 like I said you gotta go Jeff we have to 534 00:20:44,620 --> 00:20:43,070 check indeed um 535 00:20:47,950 --> 00:20:44,630 fingers crossed that it's an exciting 536 00:20:48,580 --> 00:20:47,960 system so Trappist is another solar 537 00:20:51,220 --> 00:20:48,590 system 538 00:20:53,050 --> 00:20:51,230 we're in ours and only recently have we 539 00:20:55,090 --> 00:20:53,060 found out the possibility that you can 540 00:20:57,700 --> 00:20:55,100 have material transit between solar 541 00:21:00,340 --> 00:20:57,710 systems we were visited was in a couple 542 00:21:03,640 --> 00:21:00,350 months ago by this cigar-shaped object 543 00:21:05,860 --> 00:21:03,650 called muah-muah that came from faraway 544 00:21:07,750 --> 00:21:05,870 zoom by our star and is on its way out 545 00:21:09,010 --> 00:21:07,760 and I know you've been thinking and 546 00:21:11,130 --> 00:21:09,020 studying it a little bit can you tell us 547 00:21:14,200 --> 00:21:11,140 more about this this strange body oh 548 00:21:16,780 --> 00:21:14,210 yeah this is a super exciting discovery 549 00:21:17,950 --> 00:21:16,790 it had been anticipated for decades 550 00:21:20,200 --> 00:21:17,960 people have been thinking about this 551 00:21:22,330 --> 00:21:20,210 because we know that planets you know 552 00:21:24,490 --> 00:21:22,340 planet formation is not 100% efficient 553 00:21:26,620 --> 00:21:24,500 and models have shown for a long time 554 00:21:28,420 --> 00:21:26,630 that you know a lot of the building 555 00:21:29,740 --> 00:21:28,430 blocks of planets whatever doesn't end 556 00:21:31,780 --> 00:21:29,750 up in a planet a lot of it gets chucked 557 00:21:32,710 --> 00:21:31,790 out and some of that something gets 558 00:21:35,170 --> 00:21:32,720 chucked out of other solar systems 559 00:21:37,480 --> 00:21:35,180 should wander long and come through ours 560 00:21:40,780 --> 00:21:37,490 and that's what happened so in October 561 00:21:43,360 --> 00:21:40,790 this year the pan-starrs survey out of 562 00:21:46,300 --> 00:21:43,370 Hawaii found this really fast moving 563 00:21:48,220 --> 00:21:46,310 pretty small object named Oh mwah mwah 564 00:21:52,660 --> 00:21:48,230 you know a visitor from from far away 565 00:21:55,930 --> 00:21:52,670 and so this thing is very strange it's 566 00:21:57,670 --> 00:21:55,940 it seems to be very stretched out that's 567 00:21:59,170 --> 00:21:57,680 interpreted that's inferred basically 568 00:22:02,020 --> 00:21:59,180 from its brightness variations in 569 00:22:03,670 --> 00:22:02,030 brightness changes by about two and half 570 00:22:06,790 --> 00:22:03,680 magnitudes that's about it a factor of 571 00:22:09,010 --> 00:22:06,800 ten an actual brightness every seven 572 00:22:10,300 --> 00:22:09,020 hours or so and it's thought that that's 573 00:22:12,700 --> 00:22:10,310 because of its shape they think it's 574 00:22:14,470 --> 00:22:12,710 this kind of weird cigar shaped thing 575 00:22:15,010 --> 00:22:14,480 that's sort of humbling it's not even 576 00:22:17,380 --> 00:22:15,020 rotating 577 00:22:19,420 --> 00:22:17,390 nice way it's tumbling not along any of 578 00:22:21,520 --> 00:22:19,430 its principal accidents and every so 579 00:22:23,080 --> 00:22:21,530 often it's kind of pointed at us and so 580 00:22:26,050 --> 00:22:23,090 the surface area is so small that the 581 00:22:27,790 --> 00:22:26,060 brightness dips a lot and so so that's 582 00:22:30,340 --> 00:22:27,800 one weird thing it's also weird that 583 00:22:32,920 --> 00:22:30,350 it's it passed very close to the Sun 584 00:22:36,580 --> 00:22:32,930 inside Mercury's orbit but it didn't 585 00:22:38,380 --> 00:22:36,590 give off any water or anything yet its 586 00:22:40,360 --> 00:22:38,390 colors if you measure you know its 587 00:22:43,030 --> 00:22:40,370 brightness in different wavelengths its 588 00:22:45,060 --> 00:22:43,040 colors look like objects in the solar 589 00:22:48,070 --> 00:22:45,070 system that have a lot of water like 590 00:22:50,830 --> 00:22:48,080 like C type asteroids or d-type 591 00:22:52,690 --> 00:22:50,840 asteroids or those kind of things and so 592 00:22:55,150 --> 00:22:52,700 it's this weird conundrum no one knows 593 00:22:57,310 --> 00:22:55,160 quite what to make of it 594 00:23:02,800 --> 00:22:57,320 there's this tumbling makes for a pretty 595 00:23:04,270 --> 00:23:02,810 terrible alien spaceship it's very 596 00:23:06,250 --> 00:23:04,280 similar to Arthur seek our book 597 00:23:08,500 --> 00:23:06,260 rendezvous with Rama you can just you 598 00:23:09,820 --> 00:23:08,510 know this perfect cylinder comes in the 599 00:23:12,640 --> 00:23:09,830 source I actually reread that book 600 00:23:14,800 --> 00:23:12,650 recently just after they discovered omoi 601 00:23:16,810 --> 00:23:14,810 wa because it reminded me of it 602 00:23:19,570 --> 00:23:16,820 except except the key difference like 603 00:23:21,100 --> 00:23:19,580 it's the same story humanity discovers 604 00:23:22,870 --> 00:23:21,110 this thing entering the solar system 605 00:23:25,150 --> 00:23:22,880 there's a couple little subtle 606 00:23:28,360 --> 00:23:25,160 differences like omoi was brightness 607 00:23:30,190 --> 00:23:28,370 variations are huge and in Rama they're 608 00:23:32,140 --> 00:23:30,200 tiny and the reason they're tiny and 609 00:23:33,730 --> 00:23:32,150 Rama scuzz is a smooth metal surface 610 00:23:35,100 --> 00:23:33,740 that always reflects the same amount of 611 00:23:37,540 --> 00:23:35,110 light 612 00:23:39,160 --> 00:23:37,550 so the ecliptic plane of all the planets 613 00:23:40,840 --> 00:23:39,170 is like this one more I came like 614 00:23:43,740 --> 00:23:40,850 essentially vertical and straight 615 00:23:46,330 --> 00:23:43,750 through all right can we can we back out 616 00:23:49,390 --> 00:23:46,340 the trajectory and kind of know where it 617 00:23:51,580 --> 00:23:49,400 came from people have been trying to do 618 00:23:55,060 --> 00:23:51,590 this and there's no conclusive 619 00:23:56,770 --> 00:23:55,070 determination of you know a given star 620 00:24:00,160 --> 00:23:56,780 or star forming region that it came from 621 00:24:02,800 --> 00:24:00,170 so it has its its velocity and space is 622 00:24:05,200 --> 00:24:02,810 similar to that of the nearby stars so 623 00:24:07,660 --> 00:24:05,210 that means you can't no disentangle it - 624 00:24:10,000 --> 00:24:07,670 well from just other storm so it came 625 00:24:12,460 --> 00:24:10,010 from out there somewhere so so there's 626 00:24:14,530 --> 00:24:12,470 different models for how it got there 627 00:24:17,170 --> 00:24:14,540 I have my own model so I'll explain mine 628 00:24:18,970 --> 00:24:17,180 mine is my thinking is that it's just a 629 00:24:22,480 --> 00:24:18,980 leftover from the planet you know from 630 00:24:25,300 --> 00:24:22,490 planet formation but it's probably just 631 00:24:26,740 --> 00:24:25,310 to account for for some details it I 632 00:24:28,570 --> 00:24:26,750 would think that it's not a leftover 633 00:24:32,409 --> 00:24:28,580 what's called a planet test 634 00:24:34,960 --> 00:24:32,419 but that's a leftover chunk of one so I 635 00:24:37,210 --> 00:24:34,970 think that in the process a symbol again 636 00:24:38,799 --> 00:24:37,220 I should explain this you're right 637 00:24:41,770 --> 00:24:38,809 so planetesimals basically a building 638 00:24:44,409 --> 00:24:41,780 blocks of plants things that are say ten 639 00:24:46,480 --> 00:24:44,419 hundred kilometers in size so the big 640 00:24:50,169 --> 00:24:46,490 big potato shaped things from Star Wars 641 00:24:52,029 --> 00:24:50,179 that's like a planetesimals and so so 642 00:24:53,950 --> 00:24:52,039 that's what we think plants are born 643 00:24:55,659 --> 00:24:53,960 from you know what a bunch of those form 644 00:24:57,610 --> 00:24:55,669 within these discs of gas and then they 645 00:24:59,500 --> 00:24:57,620 bash them to each other to form larger 646 00:25:03,010 --> 00:24:59,510 things they're kind of the seeds of 647 00:25:04,899 --> 00:25:03,020 plants and so when plants get big they 648 00:25:07,480 --> 00:25:04,909 have so much gravity that near planet s 649 00:25:10,450 --> 00:25:07,490 can get kicked around and if a planet as 650 00:25:12,070 --> 00:25:10,460 big as Jupiter forms its gravity is so 651 00:25:15,279 --> 00:25:12,080 strong that a lot of the stuff nearby 652 00:25:16,960 --> 00:25:15,289 gets flung into space you know it can 653 00:25:20,350 --> 00:25:16,970 give such strong gravitational kicks 654 00:25:23,169 --> 00:25:20,360 they can kick planetesimals you know out 655 00:25:25,419 --> 00:25:23,179 so fast that they never come back but 656 00:25:27,580 --> 00:25:25,429 once in a while they get really close to 657 00:25:30,310 --> 00:25:27,590 Jupiter on the way too similar to 658 00:25:31,690 --> 00:25:30,320 comment shoemaker-levy 9 and in the 659 00:25:34,630 --> 00:25:31,700 early 90s they came very close to 660 00:25:37,930 --> 00:25:34,640 Jupiter and was torn to pieces that can 661 00:25:41,529 --> 00:25:37,940 happen sometimes and so so our model is 662 00:25:44,649 --> 00:25:41,539 that that om was one of those pieces not 663 00:25:45,610 --> 00:25:44,659 a pristine planetesimals and a piece it 664 00:25:47,919 --> 00:25:45,620 was something that got torn to pieces 665 00:25:50,320 --> 00:25:47,929 torn to shreds on its way to getting 666 00:25:52,299 --> 00:25:50,330 launched into space and that can maybe 667 00:25:56,039 --> 00:25:52,309 account for why it's tumbling and it's 668 00:25:57,909 --> 00:25:56,049 weird shaped and stuff so that's awesome 669 00:25:59,680 --> 00:25:57,919 so does that mean that presumably 670 00:26:00,850 --> 00:25:59,690 there's some early pieces of our own 671 00:26:02,950 --> 00:26:00,860 solar systems that are going through 672 00:26:04,750 --> 00:26:02,960 other galaxies right now I'm not a 673 00:26:07,149 --> 00:26:04,760 legality sorry other solar systems I 674 00:26:10,180 --> 00:26:07,159 mean definitely it's it's unavoidable 675 00:26:11,529 --> 00:26:10,190 so there's pieces from there's multiple 676 00:26:14,649 --> 00:26:11,539 generations of stuff that's gotten 677 00:26:16,930 --> 00:26:14,659 kicked out basically stuff anything past 678 00:26:19,060 --> 00:26:16,940 Earth's orbit even interiors orbit there 679 00:26:20,950 --> 00:26:19,070 are pieces you know at least according 680 00:26:23,649 --> 00:26:20,960 to our computer simulations of how the 681 00:26:26,049 --> 00:26:23,659 planets form you know the process of 682 00:26:27,820 --> 00:26:26,059 planet formation is maybe half efficient 683 00:26:29,169 --> 00:26:27,830 so probably about half the building 684 00:26:31,539 --> 00:26:29,179 blocks within the solar system stuck 685 00:26:32,890 --> 00:26:31,549 around the other half got kicked out so 686 00:26:35,350 --> 00:26:32,900 most of it is probably in the form of 687 00:26:39,570 --> 00:26:35,360 small things but we may even have lost 688 00:26:41,620 --> 00:26:39,580 an ice giant that's that's an idea for 689 00:26:44,170 --> 00:26:41,630 one idea that the David 690 00:26:46,240 --> 00:26:44,180 Varney had it in swearing the idea being 691 00:26:48,060 --> 00:26:46,250 that we think the giant planets and the 692 00:26:52,600 --> 00:26:48,070 sources in Jupiter Saturn Uranus Neptune 693 00:26:54,700 --> 00:26:52,610 had a late instability and that might 694 00:26:56,860 --> 00:26:54,710 explain things like the late heavy 695 00:26:58,690 --> 00:26:56,870 bombardment and to make their models 696 00:27:01,360 --> 00:26:58,700 work much better like an order of 697 00:27:03,340 --> 00:27:01,370 magnitude better they invoke the 698 00:27:05,800 --> 00:27:03,350 existence of an extra planet at the 699 00:27:08,980 --> 00:27:05,810 start so that basically carries away 700 00:27:11,200 --> 00:27:08,990 excess energy and is ejected and so it's 701 00:27:13,300 --> 00:27:11,210 possible that that we had another planet 702 00:27:15,910 --> 00:27:13,310 or even two other planets that were 703 00:27:18,460 --> 00:27:15,920 injected shortly after they form and 704 00:27:21,430 --> 00:27:18,470 they're wandering and wandering within 705 00:27:22,750 --> 00:27:21,440 the galaxy you know I don't think we'd 706 00:27:25,330 --> 00:27:22,760 recognize them anymore but they're 707 00:27:27,790 --> 00:27:25,340 they're out there so a gas giant that's 708 00:27:29,740 --> 00:27:27,800 flying away from a star would have 709 00:27:35,140 --> 00:27:29,750 probably his its atmosphere just 710 00:27:38,740 --> 00:27:35,150 collapse down into a solid right I mean 711 00:27:41,830 --> 00:27:38,750 so so a giant planet yeah you mentioned 712 00:27:43,180 --> 00:27:41,840 an ice giant was flung out yeah I mean 713 00:27:44,290 --> 00:27:43,190 people have modeled this because it's 714 00:27:47,470 --> 00:27:44,300 not too different from the idea of 715 00:27:48,940 --> 00:27:47,480 Planet nine you know the this possible 716 00:27:50,890 --> 00:27:48,950 extra plant in the solar system that's 717 00:27:53,200 --> 00:27:50,900 out you know it's several hundred a year 718 00:27:55,540 --> 00:27:53,210 people haven't been modeling that to see 719 00:27:56,980 --> 00:27:55,550 what would it look like and so people in 720 00:27:58,930 --> 00:27:56,990 modeling you know different possible 721 00:28:00,700 --> 00:27:58,940 atmospheres what they would do it 722 00:28:04,090 --> 00:28:00,710 evolved over billions of years in very 723 00:28:06,070 --> 00:28:04,100 cold temperatures and I am afraid I 724 00:28:08,290 --> 00:28:06,080 don't know the answer but people have 725 00:28:08,890 --> 00:28:08,300 been thinking about this that's 726 00:28:13,000 --> 00:28:08,900 fascinating 727 00:28:14,590 --> 00:28:13,010 talk on this stuff for a long time and 728 00:28:16,540 --> 00:28:14,600 definitely want to switch the question 729 00:28:18,580 --> 00:28:16,550 through the Q&A time to our audience 730 00:28:20,620 --> 00:28:18,590 again if you have any questions for dr. 731 00:28:24,010 --> 00:28:20,630 Raymond please use hashtag ask Esther 732 00:28:25,870 --> 00:28:24,020 bio and we'll get them answered I'm the 733 00:28:28,780 --> 00:28:25,880 first question I see is from Jacob hello 734 00:28:30,460 --> 00:28:28,790 Jacob and he asks what are some of the 735 00:28:32,890 --> 00:28:30,470 most salient differences you have 736 00:28:34,660 --> 00:28:32,900 noticed between basic science funding in 737 00:28:38,650 --> 00:28:34,670 France and the EU compared with the 738 00:28:40,960 --> 00:28:38,660 United States ok science fun there so 739 00:28:42,520 --> 00:28:40,970 the general structure of how things are 740 00:28:47,350 --> 00:28:42,530 funded here is quite different 741 00:28:50,320 --> 00:28:47,360 so the standard track is is somewhat 742 00:28:51,670 --> 00:28:50,330 different the like are I mean I'll just 743 00:28:53,170 --> 00:28:51,680 art describing the difference in like my 744 00:28:55,120 --> 00:28:53,180 department versus departments in the 745 00:28:57,790 --> 00:28:55,130 u.s. in the US 746 00:29:00,010 --> 00:28:57,800 a professor has many grad students and 747 00:29:02,290 --> 00:29:00,020 postdocs and there's kind of this sort 748 00:29:04,540 --> 00:29:02,300 of like pyramid shape where there's one 749 00:29:07,210 --> 00:29:04,550 or maybe a few people with permanent 750 00:29:09,340 --> 00:29:07,220 jobs and a lot of people with temporary 751 00:29:12,460 --> 00:29:09,350 jobs those dogs grad students who are 752 00:29:14,770 --> 00:29:12,470 learning and and and that's kind of this 753 00:29:16,090 --> 00:29:14,780 general structure you're in France it's 754 00:29:17,350 --> 00:29:16,100 quite different and it but it changes 755 00:29:20,410 --> 00:29:17,360 from country to country because in 756 00:29:22,840 --> 00:29:20,420 Germany it's more like that pyramid type 757 00:29:24,040 --> 00:29:22,850 structure here in France is more kind of 758 00:29:28,780 --> 00:29:24,050 a higher proportion of people with 759 00:29:30,580 --> 00:29:28,790 permanent jobs and that and a few would 760 00:29:33,400 --> 00:29:30,590 rad students it's hardly harder to get 761 00:29:34,660 --> 00:29:33,410 funding for for many grad students you 762 00:29:38,320 --> 00:29:34,670 know we have some but just not quite as 763 00:29:41,050 --> 00:29:38,330 many and that just kind of changes the 764 00:29:43,210 --> 00:29:41,060 dynamic of things in terms of I guess in 765 00:29:44,830 --> 00:29:43,220 terms of overall funding for things it's 766 00:29:47,320 --> 00:29:44,840 not that different there's there's 767 00:29:48,940 --> 00:29:47,330 decent amount of astrobiology type 768 00:29:49,420 --> 00:29:48,950 research and interested in different 769 00:29:51,550 --> 00:29:49,430 things 770 00:29:54,610 --> 00:29:51,560 overall the general the means are not 771 00:29:57,160 --> 00:29:54,620 quite as big as in the US and so it's 772 00:29:59,890 --> 00:29:57,170 often oftentimes in terms of making 773 00:30:01,210 --> 00:29:59,900 decisions they kind of see where other 774 00:30:03,280 --> 00:30:01,220 places are going and trying to find a 775 00:30:06,160 --> 00:30:03,290 niche where you can have the most impact 776 00:30:08,520 --> 00:30:06,170 for your contribution rather than trying 777 00:30:10,900 --> 00:30:08,530 to repeat what someone else is doing I 778 00:30:13,660 --> 00:30:10,910 don't know that's that's what comes to 779 00:30:16,690 --> 00:30:13,670 mind yeah well thank you the next 780 00:30:18,340 --> 00:30:16,700 question is from penny who asks do you 781 00:30:20,470 --> 00:30:18,350 have a sense of how much interstellar 782 00:30:22,330 --> 00:30:20,480 organic carbon might survive the process 783 00:30:24,850 --> 00:30:22,340 of solar system formation and canotary 784 00:30:26,620 --> 00:30:24,860 accretion do you think new solar system 785 00:30:28,360 --> 00:30:26,630 has to start all over again to make 786 00:30:31,140 --> 00:30:28,370 organic carbon its plants or does it 787 00:30:36,310 --> 00:30:31,150 inherit a legacy it's good question 788 00:30:38,050 --> 00:30:36,320 that's a good one so hey I mean so I'm 789 00:30:39,850 --> 00:30:38,060 not a chemist who studies this because I 790 00:30:42,940 --> 00:30:39,860 know people do that but I think that 791 00:30:46,090 --> 00:30:42,950 that a lot of that pristine material is 792 00:30:48,240 --> 00:30:46,100 is preserved Canobie there's a debate 793 00:30:51,160 --> 00:30:48,250 you know when you're forming planets 794 00:30:54,130 --> 00:30:51,170 whether within a disc everything gets 795 00:30:57,040 --> 00:30:54,140 really hot and then rican densest or 796 00:30:58,510 --> 00:30:57,050 whether the stuff only only the stuff 797 00:31:01,000 --> 00:30:58,520 very close to the star actually gets 798 00:31:02,770 --> 00:31:01,010 that ha and the difference is if 799 00:31:04,660 --> 00:31:02,780 everything gets hot and you would lose 800 00:31:06,880 --> 00:31:04,670 volatile things maybe like organic 801 00:31:08,889 --> 00:31:06,890 carbon and then rican dancing them can 802 00:31:10,599 --> 00:31:08,899 be an issue but 803 00:31:13,539 --> 00:31:10,609 if only the area kind of close to the 804 00:31:15,849 --> 00:31:13,549 star that gets directly heated is really 805 00:31:17,469 --> 00:31:15,859 strongly heated then anything past a 806 00:31:18,609 --> 00:31:17,479 certain distance can preserve its 807 00:31:21,009 --> 00:31:18,619 garment 808 00:31:23,799 --> 00:31:21,019 my impression not being a specialist in 809 00:31:25,690 --> 00:31:23,809 this area is that people are leaning 810 00:31:27,129 --> 00:31:25,700 towards the idea that you can preserve a 811 00:31:29,739 --> 00:31:27,139 decent amount of molecules from the 812 00:31:31,029 --> 00:31:29,749 interstellar medium or at least from you 813 00:31:33,549 --> 00:31:31,039 know further out in the solar system 814 00:31:37,139 --> 00:31:33,559 and we see that you know for example in 815 00:31:38,379 --> 00:31:37,149 comets that have a lot of organic matter 816 00:31:40,359 --> 00:31:38,389 cool 817 00:31:44,769 --> 00:31:40,369 I'll keep you questions coming otherwise 818 00:31:46,570 --> 00:31:44,779 I have a bunch for harsh on myself so 819 00:31:48,099 --> 00:31:46,580 what are you working on these days do 820 00:31:50,049 --> 00:31:48,109 you have all these incredible projects 821 00:31:52,719 --> 00:31:50,059 so a bunch of different topics what how 822 00:31:54,279 --> 00:31:52,729 do you keep your attention focused well 823 00:31:58,209 --> 00:31:54,289 that's the thing I don't I don't keep it 824 00:32:00,719 --> 00:31:58,219 that focused so this is a big thing like 825 00:32:04,629 --> 00:32:00,729 how do you decide what to do next and 826 00:32:06,849 --> 00:32:04,639 you you know in grad school I had a boss 827 00:32:08,649 --> 00:32:06,859 he said you know my advisories you kind 828 00:32:11,289 --> 00:32:08,659 of pointed me in a certain direction as 829 00:32:13,060 --> 00:32:11,299 a postdoc I had applied to officially do 830 00:32:14,979 --> 00:32:13,070 a certain project 831 00:32:17,169 --> 00:32:14,989 I eventually changed directions a little 832 00:32:19,089 --> 00:32:17,179 bit and then lately over the past 833 00:32:21,279 --> 00:32:19,099 several years I had this internal debate 834 00:32:23,589 --> 00:32:21,289 like should I do things that are kind of 835 00:32:24,759 --> 00:32:23,599 doing what's already been done in what 836 00:32:25,959 --> 00:32:24,769 I've already done just kind of keep 837 00:32:28,659 --> 00:32:25,969 doing a little better and better to get 838 00:32:31,209 --> 00:32:28,669 at the details or should I look for kind 839 00:32:32,799 --> 00:32:31,219 of crazy ideas here and there and I made 840 00:32:35,019 --> 00:32:32,809 the conscious decision to try to go for 841 00:32:36,999 --> 00:32:35,029 the crazy ideas because I think they're 842 00:32:38,589 --> 00:32:37,009 kind of underrepresented and they can 843 00:32:40,329 --> 00:32:38,599 sometimes they can often be valuable 844 00:32:43,239 --> 00:32:40,339 just to get a different point of view 845 00:32:45,399 --> 00:32:43,249 and sure they're wrong a lot of the time 846 00:32:46,989 --> 00:32:45,409 too but you know as long as you stay 847 00:32:48,820 --> 00:32:46,999 bounded within reason that's it's quite 848 00:32:50,619 --> 00:32:48,830 fun and so for the past few years I've 849 00:32:53,259 --> 00:32:50,629 been I've thrown out crazy ideas about 850 00:32:55,859 --> 00:32:53,269 Jupiter for example forming right next 851 00:32:57,820 --> 00:32:55,869 to the Sun and then moving outward and 852 00:33:00,489 --> 00:32:57,830 and different things related to the 853 00:33:02,789 --> 00:33:00,499 solar system and last year I had a 854 00:33:04,869 --> 00:33:02,799 couple papers about the asteroid belt 855 00:33:07,299 --> 00:33:04,879 coming up now I'm starting to work again 856 00:33:09,279 --> 00:33:07,309 on on super-earths and their 857 00:33:11,529 --> 00:33:09,289 compositions super star super 858 00:33:14,219 --> 00:33:11,539 interesting in terms of no pun intended 859 00:33:16,599 --> 00:33:14,229 there they're interesting in terms of 860 00:33:17,589 --> 00:33:16,609 their their the plants that we're first 861 00:33:20,289 --> 00:33:17,599 going to be able to constrain the 862 00:33:22,450 --> 00:33:20,299 composition and so for some super Earths 863 00:33:24,100 --> 00:33:22,460 you can constrain their compositions you 864 00:33:26,050 --> 00:33:24,110 the time you can really do it is if 865 00:33:28,210 --> 00:33:26,060 they're very dense and then you know 866 00:33:29,620 --> 00:33:28,220 they're rocky but if they're not that 867 00:33:33,540 --> 00:33:29,630 dense then you can't tell if they're 868 00:33:36,760 --> 00:33:33,550 rock plus gas or just water and so 869 00:33:39,880 --> 00:33:36,770 telling those apart is you know is a 870 00:33:42,850 --> 00:33:39,890 tricky exercise but we can try to see 871 00:33:44,620 --> 00:33:42,860 what can you learn about plants from 872 00:33:45,940 --> 00:33:44,630 their compositions whether you can rule 873 00:33:47,470 --> 00:33:45,950 out you can never really confirm 874 00:33:50,500 --> 00:33:47,480 anything we can rule out certain 875 00:33:52,120 --> 00:33:50,510 formation histories if this kind of 876 00:33:54,700 --> 00:33:52,130 distribution with compositions is 877 00:33:55,570 --> 00:33:54,710 observed for example so to wrap up I'm 878 00:33:57,010 --> 00:33:55,580 going kind of in many different 879 00:33:59,650 --> 00:33:57,020 directions at once 880 00:33:59,920 --> 00:33:59,660 but that's sort of on purpose good for 881 00:34:04,000 --> 00:33:59,930 you 882 00:34:06,880 --> 00:34:04,010 keeps the mind busy another question we 883 00:34:08,710 --> 00:34:06,890 have from Adam Smith hi Adam he asks why 884 00:34:13,050 --> 00:34:08,720 in particular is one more very like 885 00:34:17,950 --> 00:34:13,060 cigar shaped do we have a sense of salt 886 00:34:21,820 --> 00:34:17,960 so no one knows the exact why I would 887 00:34:24,370 --> 00:34:21,830 suggest that it's indicative that I 888 00:34:27,790 --> 00:34:24,380 think it fits this general story that it 889 00:34:30,100 --> 00:34:27,800 is not a pristine object but rather one 890 00:34:32,470 --> 00:34:30,110 that was torn to pieces and so in that 891 00:34:33,820 --> 00:34:32,480 story I was telling you before about it 892 00:34:37,120 --> 00:34:33,830 kind of not being a pristine 893 00:34:40,930 --> 00:34:37,130 planetesimals Locke of planning that 894 00:34:43,780 --> 00:34:40,940 might make sense if as it was getting 895 00:34:46,030 --> 00:34:43,790 kicked out of its parent star system it 896 00:34:49,270 --> 00:34:46,040 got really close to say a Jupiter and 897 00:34:51,580 --> 00:34:49,280 was torn to pieces by tides meaning that 898 00:34:54,610 --> 00:34:51,590 you know as this object was approaching 899 00:34:57,310 --> 00:34:54,620 it's this other jupiter-like planet 900 00:34:59,680 --> 00:34:57,320 the gravity across the object was so 901 00:35:01,180 --> 00:34:59,690 strong basically the part that was 902 00:35:02,290 --> 00:35:01,190 really close to the planet was so much 903 00:35:05,200 --> 00:35:02,300 stronger than the part further away 904 00:35:06,340 --> 00:35:05,210 they've got stretched out and that 905 00:35:07,660 --> 00:35:06,350 probably wouldn't produce a woolen 906 00:35:10,720 --> 00:35:07,670 stretch that thing APRI so a whole bunch 907 00:35:12,250 --> 00:35:10,730 of a cloud of fragments but it might be 908 00:35:14,410 --> 00:35:12,260 a way to form a really stretched out 909 00:35:16,060 --> 00:35:14,420 thing apart from that I haven't heard 910 00:35:17,440 --> 00:35:16,070 about other models that could do it 911 00:35:19,480 --> 00:35:17,450 maybe it's doable by another mechanism 912 00:35:22,760 --> 00:35:19,490 too but that's that's the one that comes 913 00:35:28,190 --> 00:35:22,770 to mind well 914 00:35:30,620 --> 00:35:28,200 poke census asks Shawn if you had if you 915 00:35:32,210 --> 00:35:30,630 had to spend a couple billion euros a 916 00:35:34,359 --> 00:35:32,220 couple billion dollars 917 00:35:36,800 --> 00:35:34,369 what kind of mission would you build 918 00:35:39,050 --> 00:35:36,810 this is a good question and ask people 919 00:35:41,599 --> 00:35:39,060 this all the time so when I had this 920 00:35:43,630 --> 00:35:41,609 thought I hadn't I've had a few dinners 921 00:35:45,800 --> 00:35:43,640 with people where I asked them this and 922 00:35:49,460 --> 00:35:45,810 I've gotten different answers 923 00:35:52,340 --> 00:35:49,470 lately I still am leaning towards the 924 00:35:56,120 --> 00:35:52,350 idea of really hammering out at one 925 00:35:58,099 --> 00:35:56,130 angle really well so so a few years ago 926 00:36:01,490 --> 00:35:58,109 I would have said that I would take that 927 00:36:03,859 --> 00:36:01,500 money and I would build maybe ten big 928 00:36:06,470 --> 00:36:03,869 telescopes on the ground to do really 929 00:36:07,630 --> 00:36:06,480 precise radial velocity measurements but 930 00:36:11,000 --> 00:36:07,640 on a massive scale 931 00:36:15,170 --> 00:36:11,010 because a lot we've learned a ton from 932 00:36:16,880 --> 00:36:15,180 doing them from so so radial velocity 933 00:36:18,670 --> 00:36:16,890 measurements what that is is basically 934 00:36:21,320 --> 00:36:18,680 using a spectrograph to measure the 935 00:36:23,060 --> 00:36:21,330 velocities of stars how fast stars are 936 00:36:25,960 --> 00:36:23,070 wobbling and you can measure the 937 00:36:29,060 --> 00:36:25,970 velocity only towards are away from us 938 00:36:32,060 --> 00:36:29,070 but that's how the first several hundred 939 00:36:33,640 --> 00:36:32,070 exoplanets were found and a lot of other 940 00:36:36,380 --> 00:36:33,650 interesting things that come from that 941 00:36:39,290 --> 00:36:36,390 and spectrographs are getting more and 942 00:36:41,540 --> 00:36:39,300 more precise and you know these days the 943 00:36:43,340 --> 00:36:41,550 best ones can measure about 10 944 00:36:45,410 --> 00:36:43,350 centimeters per second of precision in 945 00:36:47,450 --> 00:36:45,420 this velocity so one option for this 946 00:36:49,730 --> 00:36:47,460 billion dollars is to build 10 of those 947 00:36:51,560 --> 00:36:49,740 and to really hammer out do a giant 948 00:36:53,599 --> 00:36:51,570 survey and have really good statistics 949 00:36:57,560 --> 00:36:53,609 to look for planets with it the other 950 00:36:59,150 --> 00:36:57,570 possibility might be to just build I 951 00:37:01,730 --> 00:36:59,160 don't know I don't remember exactly how 952 00:37:03,620 --> 00:37:01,740 much Kepler cost I think it was half a 953 00:37:05,060 --> 00:37:03,630 billion dollars something like that so I 954 00:37:09,109 --> 00:37:05,070 would just launched for Kepler's and 955 00:37:11,210 --> 00:37:09,119 just go nuts boom because I think that 956 00:37:15,050 --> 00:37:11,220 man I think the size of the stuff that 957 00:37:17,660 --> 00:37:15,060 you would get from those is is hard too 958 00:37:20,210 --> 00:37:17,670 I think we learn a lot just from doing 959 00:37:22,220 --> 00:37:20,220 the same experiments but a little better 960 00:37:24,800 --> 00:37:22,230 and longer and on a much bigger scale I 961 00:37:25,970 --> 00:37:24,810 know the idea it's always tempting and 962 00:37:28,099 --> 00:37:25,980 most of the funding goes towards 963 00:37:30,230 --> 00:37:28,109 fundamentally different projects a lot 964 00:37:32,810 --> 00:37:30,240 of it does anyway I think that that 965 00:37:35,990 --> 00:37:32,820 redoing the same one a little better can 966 00:37:38,690 --> 00:37:36,000 make big leagues 967 00:37:40,130 --> 00:37:38,700 yeah given how successful Kepler was it 968 00:37:42,010 --> 00:37:40,140 would be neat to think about what you 969 00:37:45,410 --> 00:37:42,020 could do if you had such a larger scale 970 00:37:48,980 --> 00:37:45,420 mission cool next question is from 971 00:37:52,120 --> 00:37:48,990 Melissa who asks would super-earth have 972 00:37:55,640 --> 00:37:52,130 plate tectonics like modern earth does 973 00:37:57,020 --> 00:37:55,650 so I have no idea this is a very good 974 00:37:59,570 --> 00:37:57,030 question and people are very interested 975 00:38:01,970 --> 00:37:59,580 in this because on earth you think that 976 00:38:03,920 --> 00:38:01,980 this carbonate silicate cycle that's 977 00:38:06,080 --> 00:38:03,930 driven by plate tectonics it's like the 978 00:38:07,599 --> 00:38:06,090 Earth's thermostat and so it prevents 979 00:38:11,120 --> 00:38:07,609 Earth from getting too hot or too cold 980 00:38:13,670 --> 00:38:11,130 now a lot of thing about habitability of 981 00:38:16,550 --> 00:38:13,680 other planets it's tempting to say well 982 00:38:18,950 --> 00:38:16,560 let's link it with plate tectonics now 983 00:38:21,410 --> 00:38:18,960 like I know I'm no specialist in this 984 00:38:23,030 --> 00:38:21,420 but I've seen talks by people who claim 985 00:38:26,359 --> 00:38:23,040 that there's no it's not clear that 986 00:38:27,230 --> 00:38:26,369 plate tectonics was active for a good 987 00:38:29,410 --> 00:38:27,240 chunk of Earth's history 988 00:38:31,609 --> 00:38:29,420 so it's not clear that that's really 989 00:38:34,760 --> 00:38:31,619 necessarily as important as we think on 990 00:38:36,650 --> 00:38:34,770 earth um like I said I can't really 991 00:38:40,070 --> 00:38:36,660 judge that but I've seen other studies 992 00:38:42,200 --> 00:38:40,080 get this for it for supers and it seems 993 00:38:45,560 --> 00:38:42,210 that all of the key kind of stresses 994 00:38:47,810 --> 00:38:45,570 that are that play a role in causing 995 00:38:50,660 --> 00:38:47,820 plate tectonics on earth should be a 996 00:38:53,180 --> 00:38:50,670 little bit stronger that's right my 997 00:38:55,460 --> 00:38:53,190 understanding from seeing papers is that 998 00:38:57,500 --> 00:38:55,470 it's it's likely that plate tectonics or 999 00:39:01,030 --> 00:38:57,510 it's more likely than not that plate 1000 00:39:03,560 --> 00:39:01,040 tectonics can't operate on unser groans 1001 00:39:05,660 --> 00:39:03,570 yeah these perhaps plate tectonics not 1002 00:39:07,670 --> 00:39:05,670 necessarily for life to start but could 1003 00:39:10,040 --> 00:39:07,680 be necessary to sustain life on a planet 1004 00:39:13,420 --> 00:39:10,050 for several billion years interesting 1005 00:39:15,770 --> 00:39:13,430 question I'm not gonna hurt anyway yeah 1006 00:39:19,900 --> 00:39:15,780 all right the next question is from Ned 1007 00:39:22,520 --> 00:39:19,910 Senate hello and he or she asks about 1008 00:39:24,650 --> 00:39:22,530 gold and platinum formation at what 1009 00:39:26,630 --> 00:39:24,660 stage do we get to these to these 1010 00:39:31,790 --> 00:39:26,640 elements and in country formation 1011 00:39:33,980 --> 00:39:31,800 history so gold and platinum stuff I 1012 00:39:37,339 --> 00:39:33,990 believe they're part of the rare earth 1013 00:39:40,329 --> 00:39:37,349 elements if I'm not mistaken and those 1014 00:39:42,470 --> 00:39:40,339 are not very abundant on our surface 1015 00:39:44,540 --> 00:39:42,480 they're thought to have been brought in 1016 00:39:47,329 --> 00:39:44,550 basically they're really interesting on 1017 00:39:49,490 --> 00:39:47,339 earth because they're thought to follow 1018 00:39:49,730 --> 00:39:49,500 iron and so why do we care about this 1019 00:39:51,920 --> 00:39:49,740 how 1020 00:39:54,530 --> 00:39:51,930 earth form uniform through a succession 1021 00:39:56,660 --> 00:39:54,540 of big impacts and whenever there was 1022 00:39:58,640 --> 00:39:56,670 enough a strong enough impact we think 1023 00:40:01,010 --> 00:39:58,650 that there was a core forming event 1024 00:40:03,710 --> 00:40:01,020 basically the earth got you know molten 1025 00:40:05,240 --> 00:40:03,720 enough that iron sunk in the core and it 1026 00:40:07,880 --> 00:40:05,250 dragged all these other things with it 1027 00:40:09,890 --> 00:40:07,890 like gold and platinum and iridium is 1028 00:40:11,000 --> 00:40:09,900 one that's often used to traces too but 1029 00:40:13,160 --> 00:40:11,010 these kind of elements got sucked into 1030 00:40:14,840 --> 00:40:13,170 the core and so you can imagine if earth 1031 00:40:17,120 --> 00:40:14,850 formed by these big collisions and it's 1032 00:40:18,260 --> 00:40:17,130 final you know the final thing in 1033 00:40:20,870 --> 00:40:18,270 Earth's formation was a big collision 1034 00:40:22,609 --> 00:40:20,880 all that iron all that gold platinum 1035 00:40:24,920 --> 00:40:22,619 would be sucked in the core and we would 1036 00:40:26,420 --> 00:40:24,930 have none we wouldn't have I got a gold 1037 00:40:28,400 --> 00:40:26,430 ring man you we wouldn't have these 1038 00:40:30,560 --> 00:40:28,410 kinds of things there wouldn't be any on 1039 00:40:33,290 --> 00:40:30,570 the surface but there is so we think 1040 00:40:35,630 --> 00:40:33,300 that it came from the small amount of 1041 00:40:37,490 --> 00:40:35,640 material that hit the earth after the 1042 00:40:40,280 --> 00:40:37,500 last giant impact we think the last 1043 00:40:42,710 --> 00:40:40,290 giant impact was the one that was not 1044 00:40:45,620 --> 00:40:42,720 perfect impact it spun out a disc of 1045 00:40:49,430 --> 00:40:45,630 stuff and from that disc the moon formed 1046 00:40:53,180 --> 00:40:49,440 and after that happened we think about 1047 00:40:55,970 --> 00:40:53,190 half a percent of Earth's mass hit the 1048 00:40:58,670 --> 00:40:55,980 earth after that and so earth still was 1049 00:41:00,800 --> 00:40:58,680 able to accumulate some material 1050 00:41:05,000 --> 00:41:00,810 afterward it's bringing along all the 1051 00:41:08,090 --> 00:41:05,010 gold that we have cool thank you it's 1052 00:41:11,359 --> 00:41:08,100 the story our next question is from Maya 1053 00:41:13,490 --> 00:41:11,369 who asks if we are able if we detect one 1054 00:41:15,470 --> 00:41:13,500 of those wandering bodies planet-sized 1055 00:41:16,940 --> 00:41:15,480 bodies how would we be able to tell 1056 00:41:20,270 --> 00:41:16,950 whether it comes from our own solar 1057 00:41:24,859 --> 00:41:20,280 system I don't see how you would ever 1058 00:41:28,760 --> 00:41:24,869 tell it'll be awesome if we could so no 1059 00:41:31,040 --> 00:41:28,770 so I don't see how he would it'd be 1060 00:41:32,840 --> 00:41:31,050 really neat you know if we think like I 1061 00:41:35,420 --> 00:41:32,850 was saying the earth I mean the SOI 1062 00:41:37,220 --> 00:41:35,430 system lost probably lost an ice giant 1063 00:41:39,170 --> 00:41:37,230 you know according to these models and 1064 00:41:41,990 --> 00:41:39,180 as the terrestrial planets were forming 1065 00:41:45,530 --> 00:41:42,000 probably lost several Mars size objects 1066 00:41:47,630 --> 00:41:45,540 now we can detect these hopefully we'll 1067 00:41:49,490 --> 00:41:47,640 be able to detect these by microlensing 1068 00:41:52,640 --> 00:41:49,500 like with the W first mission in the 1069 00:41:54,470 --> 00:41:52,650 next you know decade or so but otherwise 1070 00:41:56,450 --> 00:41:54,480 you know they're not abundant enough 1071 00:41:58,160 --> 00:41:56,460 that we expect them to fly by and if we 1072 00:42:00,500 --> 00:41:58,170 happen to get super lucky and one did 1073 00:42:02,450 --> 00:42:00,510 fly by well it wouldn't be great for the 1074 00:42:05,150 --> 00:42:02,460 stability the solar system 1075 00:42:07,370 --> 00:42:05,160 but we also this all happened so long 1076 00:42:09,560 --> 00:42:07,380 ago that we wouldn't be able to trade 1077 00:42:10,609 --> 00:42:09,570 the back I mean it takes if I remember 1078 00:42:12,349 --> 00:42:10,619 it takes the Sun a couple hundred 1079 00:42:15,380 --> 00:42:12,359 million years to do a loop around the 1080 00:42:17,120 --> 00:42:15,390 center of the galaxy and the solar 1081 00:42:18,079 --> 00:42:17,130 system is what four and four and a half 1082 00:42:20,000 --> 00:42:18,089 billion years old 1083 00:42:22,430 --> 00:42:20,010 so that's more than twenty of these and 1084 00:42:24,530 --> 00:42:22,440 so anything that was launched from the 1085 00:42:27,800 --> 00:42:24,540 solar system is gone we're not gonna be 1086 00:42:30,440 --> 00:42:27,810 able to trace it back interesting good 1087 00:42:33,710 --> 00:42:30,450 question Maya so humans are currently 1088 00:42:35,030 --> 00:42:33,720 kind of stuck on earth right but it goes 1089 00:42:37,520 --> 00:42:35,040 without saying that we're trying really 1090 00:42:39,829 --> 00:42:37,530 hard to get out of it and perhaps some 1091 00:42:41,780 --> 00:42:39,839 of our soon new destinations will be 1092 00:42:45,560 --> 00:42:41,790 Mars and they'll be nice to think about 1093 00:42:49,910 --> 00:42:45,570 making Mars habitable artificially for 1094 00:42:50,780 --> 00:42:49,920 humans um come Rosamond Tony I apologize 1095 00:42:52,820 --> 00:42:50,790 if I didn't pronounce your name 1096 00:42:55,010 --> 00:42:52,830 correctly is thinking about microalgae 1097 00:42:58,040 --> 00:42:55,020 in a large scale to produce oxygen and 1098 00:42:59,210 --> 00:42:58,050 food for humans on another planet what 1099 00:43:00,650 --> 00:42:59,220 are your thoughts about you know 1100 00:43:03,920 --> 00:43:00,660 terraforming in other planets using 1101 00:43:06,200 --> 00:43:03,930 technology or otherwise I mean I think 1102 00:43:10,760 --> 00:43:06,210 it's the way to go on the for Humanity 1103 00:43:12,079 --> 00:43:10,770 on the long-term I think if we stay I've 1104 00:43:13,190 --> 00:43:12,089 heard this described by people and I 1105 00:43:17,030 --> 00:43:13,200 think it's a really good argument that 1106 00:43:19,700 --> 00:43:17,040 if we stay on earth then we're at risk 1107 00:43:25,040 --> 00:43:19,710 at risk of some kind of Cataclysm wiping 1108 00:43:26,630 --> 00:43:25,050 us out now if humanity wants to you know 1109 00:43:28,220 --> 00:43:26,640 make sure to preserve itself for the 1110 00:43:30,589 --> 00:43:28,230 long term which we don't have to want to 1111 00:43:32,450 --> 00:43:30,599 but but assuming we do then the way to 1112 00:43:35,120 --> 00:43:32,460 predict you know one way to protect it 1113 00:43:37,010 --> 00:43:35,130 I've kind of first key step you know 1114 00:43:39,050 --> 00:43:37,020 astronomically speaking is to make it so 1115 00:43:40,880 --> 00:43:39,060 that we're not reliant on one object so 1116 00:43:44,570 --> 00:43:40,890 that one bad event can can't wipe us out 1117 00:43:46,609 --> 00:43:44,580 and so you got to go to wherever you 1118 00:43:49,160 --> 00:43:46,619 know wherever the next best place that's 1119 00:43:50,930 --> 00:43:49,170 you know within the same system for for 1120 00:43:53,690 --> 00:43:50,940 life and Mars is a pretty good candidate 1121 00:43:58,010 --> 00:43:53,700 since it's nearby it's you know it's not 1122 00:44:01,000 --> 00:43:58,020 it's not habitable obviously now but you 1123 00:44:04,970 --> 00:44:01,010 know it seems like it has resources for 1124 00:44:06,980 --> 00:44:04,980 starting things over so I totally agree 1125 00:44:08,660 --> 00:44:06,990 with that sentiment and I think in the 1126 00:44:10,630 --> 00:44:08,670 coming you know centuries that'll be 1127 00:44:12,750 --> 00:44:10,640 something that's a really big though 1128 00:44:15,240 --> 00:44:12,760 indeed indeed 1129 00:44:18,630 --> 00:44:15,250 and next question is from Nitin who is 1130 00:44:22,680 --> 00:44:18,640 also has a question about umemura do we 1131 00:44:26,100 --> 00:44:22,690 have a sense of how old it is no we 1132 00:44:28,890 --> 00:44:26,110 can't tell so so one thing that's I 1133 00:44:30,960 --> 00:44:28,900 mentioned this briefly but so all the 1134 00:44:34,260 --> 00:44:30,970 stars kind of in the neighborhood in the 1135 00:44:35,760 --> 00:44:34,270 galaxy they have a characteristic kind 1136 00:44:38,220 --> 00:44:35,770 of speeds as they zoom in around and 1137 00:44:39,930 --> 00:44:38,230 stars that are born tend to be born with 1138 00:44:43,830 --> 00:44:39,940 lower speeds and in time they kind of 1139 00:44:46,140 --> 00:44:43,840 get excited and so you know if if Oh 1140 00:44:48,360 --> 00:44:46,150 mwah mwah speed was very low 1141 00:44:49,440 --> 00:44:48,370 you know relative to the galactic point 1142 00:44:51,360 --> 00:44:49,450 of you know and the galactic point of 1143 00:44:54,060 --> 00:44:51,370 view and we could kind of argue that it 1144 00:44:57,080 --> 00:44:54,070 was probably on the young son but it has 1145 00:45:01,320 --> 00:44:57,090 the similar speeds to nearby stars and 1146 00:45:02,730 --> 00:45:01,330 so you can't say anything it's really it 1147 00:45:05,910 --> 00:45:02,740 would be awesome to have better 1148 00:45:10,230 --> 00:45:05,920 constraints but right now it's really we 1149 00:45:12,450 --> 00:45:10,240 don't know that's a fine answer you are 1150 00:45:14,400 --> 00:45:12,460 very active in public outreach of 1151 00:45:16,230 --> 00:45:14,410 science and you have a fantastic block 1152 00:45:17,460 --> 00:45:16,240 or planet planet but net that I 1153 00:45:19,830 --> 00:45:17,470 encourage all of you who are listening 1154 00:45:21,450 --> 00:45:19,840 and watching to go check out could you 1155 00:45:22,920 --> 00:45:21,460 tell us how that block started and how 1156 00:45:26,280 --> 00:45:22,930 you integrate ArtReach was your 1157 00:45:28,880 --> 00:45:26,290 professional scientific career sure so 1158 00:45:32,190 --> 00:45:28,890 the blog started I mentioned it briefly 1159 00:45:33,780 --> 00:45:32,200 that when I was a kid I wanted to be 1160 00:45:36,600 --> 00:45:33,790 well I want to be a baseball player but 1161 00:45:38,370 --> 00:45:36,610 that didn't happen then I had a phase 1162 00:45:40,320 --> 00:45:38,380 where I want to be a writer and then 1163 00:45:42,540 --> 00:45:40,330 after a while you know I became less 1164 00:45:43,860 --> 00:45:42,550 interested in being a writer and veered 1165 00:45:45,990 --> 00:45:43,870 towards other things eventually I know 1166 00:45:47,760 --> 00:45:46,000 up in science but I've always kind of 1167 00:45:49,590 --> 00:45:47,770 had this interest in writing a book it 1168 00:45:53,370 --> 00:45:49,600 was kind of always on my bucket list and 1169 00:45:56,400 --> 00:45:53,380 so a few years ago I acted some people 1170 00:45:58,260 --> 00:45:56,410 actually won got Caleb shark at Columbia 1171 00:45:59,940 --> 00:45:58,270 I talked with him a bit because he 1172 00:46:02,040 --> 00:45:59,950 writes science books that are really 1173 00:46:05,550 --> 00:46:02,050 good and so I asked him how he got into 1174 00:46:06,840 --> 00:46:05,560 this and he he suggested he he liked I 1175 00:46:09,360 --> 00:46:06,850 had an idea for a book he liked the idea 1176 00:46:11,430 --> 00:46:09,370 he suggested starting a blog just to 1177 00:46:13,530 --> 00:46:11,440 practice that kind of writing writing 1178 00:46:15,270 --> 00:46:13,540 for not writing for scientists and 1179 00:46:16,560 --> 00:46:15,280 technical way but trying to write in a 1180 00:46:18,420 --> 00:46:16,570 way that hopefully other people can 1181 00:46:20,310 --> 00:46:18,430 understand even if they don't have the 1182 00:46:22,200 --> 00:46:20,320 background you know all the scientific 1183 00:46:25,710 --> 00:46:22,210 training and so I started the blog just 1184 00:46:28,110 --> 00:46:25,720 to practice and once I did it for 1185 00:46:30,180 --> 00:46:28,120 I start really annoying and it just kind 1186 00:46:31,920 --> 00:46:30,190 of kept going from there and I'm 1187 00:46:34,170 --> 00:46:31,930 thinking about writing a book still but 1188 00:46:35,730 --> 00:46:34,180 I I still have the blog and so one thing 1189 00:46:37,620 --> 00:46:35,740 one fun thing I do in the blog is you 1190 00:46:40,220 --> 00:46:37,630 know I do some stuff that's kind of to 1191 00:46:42,780 --> 00:46:40,230 be expected I summarized recent results 1192 00:46:45,690 --> 00:46:42,790 but I also do things that are kind of 1193 00:46:47,790 --> 00:46:45,700 imaginative science like one experiment 1194 00:46:49,650 --> 00:46:47,800 that I did on my blog that for the first 1195 00:46:53,160 --> 00:46:49,660 year my blog got all the traffic pretty 1196 00:46:55,290 --> 00:46:53,170 much was to say imagine right in our 1197 00:46:57,750 --> 00:46:55,300 solar system we have eight planets a 1198 00:47:00,330 --> 00:46:57,760 whole bunch of moons but we have one 1199 00:47:03,180 --> 00:47:00,340 habitable planet and that's it is there 1200 00:47:05,490 --> 00:47:03,190 a way to preserve all the orbits and all 1201 00:47:07,620 --> 00:47:05,500 the objects in the solar system but 1202 00:47:10,110 --> 00:47:07,630 rearrange them and end up with a system 1203 00:47:11,250 --> 00:47:10,120 that has more than one habitable one you 1204 00:47:13,560 --> 00:47:11,260 know that you can argue quite 1205 00:47:16,020 --> 00:47:13,570 convincingly it should more than one of 1206 00:47:18,240 --> 00:47:16,030 those should be habitable and and what I 1207 00:47:20,010 --> 00:47:18,250 did in this blog post as I kept earth 1208 00:47:22,980 --> 00:47:20,020 there I moved out the moon and I 1209 00:47:25,230 --> 00:47:22,990 substituted think Europa or maybe Titan 1210 00:47:27,480 --> 00:47:25,240 you know a large moon of Jupiter Saturn 1211 00:47:30,360 --> 00:47:27,490 I got rid of Mars since we know 1212 00:47:32,010 --> 00:47:30,370 empirically and even though it's in you 1213 00:47:33,510 --> 00:47:32,020 know it's it's wooden many estimates of 1214 00:47:35,370 --> 00:47:33,520 the habitable zone you know it's not 1215 00:47:37,800 --> 00:47:35,380 doing it it's not habitable so I checked 1216 00:47:39,510 --> 00:47:37,810 out Mars and I moved Jupiter there and I 1217 00:47:40,680 --> 00:47:39,520 gave it a bunch of big moons all the 1218 00:47:44,550 --> 00:47:40,690 biggest moves I think I might have put 1219 00:47:46,650 --> 00:47:44,560 Mars as a moon of Jupiter and in the end 1220 00:47:48,390 --> 00:47:46,660 you know I could kind of argue that I 1221 00:47:50,760 --> 00:47:48,400 ended up with something like you know 1222 00:47:53,970 --> 00:47:50,770 six or seven habitable worlds and so 1223 00:47:55,560 --> 00:47:53,980 that kind of experiment on the blog got 1224 00:47:56,790 --> 00:47:55,570 a lot of attention people were really 1225 00:47:59,130 --> 00:47:56,800 interested in it and so then I kept 1226 00:48:02,040 --> 00:47:59,140 going and and integrating kind of 1227 00:48:03,990 --> 00:48:02,050 science with imaginative snakes and when 1228 00:48:07,170 --> 00:48:04,000 I do that it's when I get the best 1229 00:48:10,080 --> 00:48:07,180 response from people so so yeah the blog 1230 00:48:13,200 --> 00:48:10,090 is really fun I really enjoy it and it 1231 00:48:15,240 --> 00:48:13,210 kind of beers between you know very more 1232 00:48:19,560 --> 00:48:15,250 serious science stuff and more almost 1233 00:48:21,630 --> 00:48:19,570 science fictiony stuff but I like it 1234 00:48:23,640 --> 00:48:21,640 when people get interested in so you 1235 00:48:26,310 --> 00:48:23,650 mentioned that you had sci-fi writers 1236 00:48:29,250 --> 00:48:26,320 contact you about using the solar 1237 00:48:31,800 --> 00:48:29,260 systems that you've simulated and using 1238 00:48:33,150 --> 00:48:31,810 physics no to be stable and if they 1239 00:48:36,960 --> 00:48:33,160 could use that for their own stories 1240 00:48:38,520 --> 00:48:36,970 that's awesome yeah yeah that was fun so 1241 00:48:39,010 --> 00:48:38,530 following that same theme that I was 1242 00:48:40,480 --> 00:48:39,020 talking about 1243 00:48:42,730 --> 00:48:40,490 about making the solar system better I 1244 00:48:44,920 --> 00:48:42,740 decided to throw everything I know about 1245 00:48:46,270 --> 00:48:44,930 orbital dynamics in there to build the 1246 00:48:46,900 --> 00:48:46,280 ultimate solar system that's what I 1247 00:48:49,090 --> 00:48:46,910 called it 1248 00:48:50,890 --> 00:48:49,100 so the question being how many planets 1249 00:48:52,960 --> 00:48:50,900 can you in theory pack into the 1250 00:48:57,790 --> 00:48:52,970 habitable zone and the last one I did 1251 00:48:58,990 --> 00:48:57,800 maybe six months ago I got 400 it which 1252 00:49:01,630 --> 00:48:59,000 doesn't seem possible but you can 1253 00:49:05,080 --> 00:49:01,640 actually have a ring of planets orbiting 1254 00:49:08,560 --> 00:49:05,090 all in the same orbit remain stable and 1255 00:49:11,680 --> 00:49:08,570 you could have missing 400 yeah you so 1256 00:49:14,380 --> 00:49:11,690 so I even I I was basing this on recent 1257 00:49:16,600 --> 00:49:14,390 papers in in in celestial mechanics and 1258 00:49:18,400 --> 00:49:16,610 I was I was skeptical about it so I ran 1259 00:49:21,070 --> 00:49:18,410 my own and body simulations to test it 1260 00:49:24,520 --> 00:49:21,080 and you can have four hundred and 1261 00:49:27,790 --> 00:49:24,530 sixteen I think you know about earth 1262 00:49:29,200 --> 00:49:27,800 sized planets in the habitable zone no I 1263 00:49:31,780 --> 00:49:29,210 don't think they would ever end up that 1264 00:49:33,550 --> 00:49:31,790 way and so so in the blog post you know 1265 00:49:35,890 --> 00:49:33,560 argue the only way you could get that is 1266 00:49:38,650 --> 00:49:35,900 if some advanced civilization designed 1267 00:49:39,400 --> 00:49:38,660 it that way you know and if they 1268 00:49:41,260 --> 00:49:39,410 designed it that way 1269 00:49:47,020 --> 00:49:41,270 couldn't they just take any planet make 1270 00:49:49,210 --> 00:49:47,030 it habitable anyway and then uh but in a 1271 00:49:51,070 --> 00:49:49,220 case it's really interesting to kind of 1272 00:49:53,350 --> 00:49:51,080 combine science with the science fiction 1273 00:49:55,030 --> 00:49:53,360 in this way awesome and to remind 1274 00:49:57,490 --> 00:49:55,040 everybody your blog is that planet 1275 00:49:59,440 --> 00:49:57,500 planet nets I encourage you to go check 1276 00:50:01,030 --> 00:49:59,450 it out and we have one question again 1277 00:50:05,860 --> 00:50:01,040 from Newton he wants to follow up with 1278 00:50:08,130 --> 00:50:05,870 from his mower question is does Earth is 1279 00:50:11,080 --> 00:50:08,140 there risk to Earth from one of these 1280 00:50:13,270 --> 00:50:11,090 extrasolar bodies that come suing by and 1281 00:50:17,410 --> 00:50:13,280 can potentially cause damage to our own 1282 00:50:21,880 --> 00:50:17,420 planet no I mean the impact probability 1283 00:50:24,280 --> 00:50:21,890 with them is tiny compared birth you 1284 00:50:26,410 --> 00:50:24,290 know gets hit by very small space junk 1285 00:50:28,000 --> 00:50:26,420 all the time and very large 1286 00:50:30,910 --> 00:50:28,010 excuse me space junk you know very 1287 00:50:32,770 --> 00:50:30,920 rarely and the biggest risk we have now 1288 00:50:35,410 --> 00:50:32,780 from class of asteroids that cross 1289 00:50:37,570 --> 00:50:35,420 Earth's orbit and even those that that 1290 00:50:39,460 --> 00:50:37,580 are crossing Earth's orbit you know 1291 00:50:41,130 --> 00:50:39,470 statistically hit us once every hundred 1292 00:50:43,270 --> 00:50:41,140 million years or something like that 1293 00:50:45,820 --> 00:50:43,280 these objects that are coming in at 1294 00:50:47,770 --> 00:50:45,830 crazy crazy angles have a much smaller 1295 00:50:50,290 --> 00:50:47,780 target effectively that they're aiming 1296 00:50:52,510 --> 00:50:50,300 for so the the risk from them is very 1297 00:50:55,030 --> 00:50:52,520 very small it's not like it's not zero 1298 00:50:59,920 --> 00:50:55,040 point zero but it's very small right 1299 00:51:01,390 --> 00:50:59,930 right so we can sleep safe tonight so 1300 00:51:02,650 --> 00:51:01,400 Shawn if you have if we have listeners 1301 00:51:04,390 --> 00:51:02,660 our students and want to become 1302 00:51:06,730 --> 00:51:04,400 professional astronomers and n-body 1303 00:51:08,890 --> 00:51:06,740 simulators that feels in scientific 1304 00:51:13,360 --> 00:51:08,900 areas similar to yours what advice would 1305 00:51:15,730 --> 00:51:13,370 you give them so a few years ago I would 1306 00:51:18,460 --> 00:51:15,740 always encourage people to to learn 1307 00:51:20,680 --> 00:51:18,470 computing because in grad school one 1308 00:51:21,910 --> 00:51:20,690 thing I had actually taken the a decent 1309 00:51:24,100 --> 00:51:21,920 amount of computer science stuff in 1310 00:51:26,680 --> 00:51:24,110 college and so I felt really happy that 1311 00:51:29,320 --> 00:51:26,690 I had because I knew how to do basic 1312 00:51:31,060 --> 00:51:29,330 stuff enough enough that I could kind of 1313 00:51:34,690 --> 00:51:31,070 basically I had the tools to learn more 1314 00:51:37,360 --> 00:51:34,700 and I used to always encourage do that I 1315 00:51:38,920 --> 00:51:37,370 don't know I'm not like since my kids 1316 00:51:42,010 --> 00:51:38,930 are the wrong age to notice ant like I 1317 00:51:44,050 --> 00:51:42,020 don't know how well people who were 1318 00:51:45,760 --> 00:51:44,060 entering grad school now like how much 1319 00:51:47,770 --> 00:51:45,770 computer training they have where that 1320 00:51:51,070 --> 00:51:47,780 it's common to already know how to use 1321 00:51:52,930 --> 00:51:51,080 you know linux-based systems and this 1322 00:51:57,880 --> 00:51:52,940 kind of stuff or not so I'm not sure how 1323 00:52:01,330 --> 00:51:57,890 relevant that is anymore but that's a 1324 00:52:04,180 --> 00:52:01,340 key thing anyway apart from that I I 1325 00:52:07,120 --> 00:52:04,190 would encourage people not to not to be 1326 00:52:11,980 --> 00:52:07,130 you know single-minded about stuff and 1327 00:52:14,950 --> 00:52:11,990 to you know to read other subjects and 1328 00:52:18,190 --> 00:52:14,960 to you know read science fiction this 1329 00:52:19,960 --> 00:52:18,200 kind of stuff just in the interests not 1330 00:52:21,010 --> 00:52:19,970 you know not that you're gonna go become 1331 00:52:22,890 --> 00:52:21,020 necessarily a science fiction writer 1332 00:52:25,780 --> 00:52:22,900 although you know why not if you want to 1333 00:52:27,630 --> 00:52:25,790 but just to kind of keep your mind used 1334 00:52:32,230 --> 00:52:27,640 to jumping around to different ideas 1335 00:52:34,270 --> 00:52:32,240 because a common danger in science is to 1336 00:52:36,310 --> 00:52:34,280 you know to be very your peer smart 1337 00:52:38,440 --> 00:52:36,320 enough you get into grad school you do a 1338 00:52:40,420 --> 00:52:38,450 project with your adviser you keep 1339 00:52:42,550 --> 00:52:40,430 pushing through and you do that project 1340 00:52:44,080 --> 00:52:42,560 and maybe you're very good at it you get 1341 00:52:46,750 --> 00:52:44,090 your PhD and then it's like what do you 1342 00:52:48,640 --> 00:52:46,760 do next and oftentimes the answer is 1343 00:52:51,250 --> 00:52:48,650 well I know how to do this so I'm gonna 1344 00:52:52,630 --> 00:52:51,260 keep doing that and that's not 1345 00:52:54,640 --> 00:52:52,640 necessarily the best use of your 1346 00:52:56,110 --> 00:52:54,650 resources if you happen to be the world 1347 00:52:57,610 --> 00:52:56,120 expert and you're gonna do the best at 1348 00:52:59,950 --> 00:52:57,620 that then sure why not 1349 00:53:01,210 --> 00:52:59,960 I'm not against Duke even doing that but 1350 00:53:04,750 --> 00:53:01,220 I think there's kind of missed 1351 00:53:05,770 --> 00:53:04,760 opportunities often by people having 1352 00:53:07,630 --> 00:53:05,780 kind of tunnel vision 1353 00:53:09,970 --> 00:53:07,640 and so just trying to break out of that 1354 00:53:12,160 --> 00:53:09,980 kind of tunnel vision in different ways 1355 00:53:15,310 --> 00:53:12,170 I think is very useful and not really 1356 00:53:16,840 --> 00:53:15,320 talked about very much that's a 1357 00:53:18,790 --> 00:53:16,850 fantastic note to end with very 1358 00:53:20,560 --> 00:53:18,800 astrobiological irrelevance when you get 1359 00:53:23,080 --> 00:53:20,570 insights from your discipline from 1360 00:53:25,330 --> 00:53:23,090 outside so on that note I wanna thank 1361 00:53:26,830 --> 00:53:25,340 you in particular and our audience for 1362 00:53:29,170 --> 00:53:26,840 sticking out and listening to our 1363 00:53:30,940 --> 00:53:29,180 presentation today it was wonderful to 1364 00:53:32,350 --> 00:53:30,950 have you Sean I know it's late in Europe 1365 00:53:35,050 --> 00:53:32,360 right now so thanks for taking the time 1366 00:53:38,020 --> 00:53:35,060 please join us next time for another ask 1367 00:53:38,570 --> 00:53:38,030 and astrobiologist and until then stay 1368 00:54:17,510 --> 00:53:38,580 curious