1 00:00:35,880 --> 00:00:33,620 [Music] 2 00:00:38,310 --> 00:00:35,890 greetings to my friends and fellow 3 00:00:40,680 --> 00:00:38,320 earthlings and welcome to ask an 4 00:00:43,979 --> 00:00:40,690 astrobiologist the show that celebrates 5 00:00:46,410 --> 00:00:43,989 the science and the scientists involved 6 00:00:47,700 --> 00:00:46,420 in our quest to understand the nature of 7 00:00:50,369 --> 00:00:47,710 life in the cosmos 8 00:00:53,100 --> 00:00:50,379 I'm your host Graham Lau also known 9 00:00:55,200 --> 00:00:53,110 online as the Cosmo biologist and we're 10 00:00:58,140 --> 00:00:55,210 brought to you by Sagan net org and the 11 00:00:59,880 --> 00:00:58,150 NASA Astrobiology program now I've got 12 00:01:01,680 --> 00:00:59,890 to tell you for all of our longtime fans 13 00:01:04,110 --> 00:01:01,690 watching I'm super jazzed for this 14 00:01:05,460 --> 00:01:04,120 episode it's gonna be groovy we have dr. 15 00:01:07,350 --> 00:01:05,470 Eddie Spearman coming on we're going to 16 00:01:09,860 --> 00:01:07,360 talk about all kinds of things like 17 00:01:11,760 --> 00:01:09,870 exoplanets and bio signatures 18 00:01:14,190 --> 00:01:11,770 understanding earth through time and 19 00:01:16,200 --> 00:01:14,200 habitable zones and then more so it's 20 00:01:17,910 --> 00:01:16,210 gonna be super awesome but we do have 21 00:01:20,250 --> 00:01:17,920 some of our fun old housekeeping stuff 22 00:01:22,620 --> 00:01:20,260 to do first for instance we have our 23 00:01:25,020 --> 00:01:22,630 field site challenge that we do every 24 00:01:27,390 --> 00:01:25,030 month just before the episode we release 25 00:01:31,140 --> 00:01:27,400 a picture on the Twitter feed for Sagan 26 00:01:33,000 --> 00:01:31,150 net at Sagan org and we ask you where in 27 00:01:35,460 --> 00:01:33,010 the world or the universe is this 28 00:01:37,770 --> 00:01:35,470 location and maybe even tell us why it's 29 00:01:39,270 --> 00:01:37,780 important to ask for biology and so the 30 00:01:41,430 --> 00:01:39,280 image from this month is popping up 31 00:01:43,560 --> 00:01:41,440 right now it's this really weird 32 00:01:46,590 --> 00:01:43,570 strawberry milkshake of a lake 33 00:01:49,680 --> 00:01:46,600 this is Lake Hillier it's a hyper saline 34 00:01:51,930 --> 00:01:49,690 Lake and middle island off the south 35 00:01:55,770 --> 00:01:51,940 coast of Western Australia and that 36 00:01:58,380 --> 00:01:55,780 bubblegum pink coloration is caused by a 37 00:02:02,880 --> 00:01:58,390 little bit of life there's an organism 38 00:02:06,210 --> 00:02:02,890 called Denali ala Salina it's a green 39 00:02:08,399 --> 00:02:06,220 unicellular algae that produces a very 40 00:02:10,559 --> 00:02:08,409 large amount of pigments inside of its 41 00:02:12,210 --> 00:02:10,569 body or inside of its cell these 42 00:02:14,430 --> 00:02:12,220 organisms can survive very salty 43 00:02:16,880 --> 00:02:14,440 environments up to 35% salt 44 00:02:19,860 --> 00:02:16,890 concentrations like hyper saline lakes 45 00:02:22,229 --> 00:02:19,870 like this Lake Hillier and they also 46 00:02:24,930 --> 00:02:22,239 produce up to something around 10% of 47 00:02:26,789 --> 00:02:24,940 their dry mass and beta carotene and so 48 00:02:28,559 --> 00:02:26,799 we've actually used them in cosmetics 49 00:02:30,509 --> 00:02:28,569 and other places because they produce so 50 00:02:32,180 --> 00:02:30,519 much beta-carotene but it's also 51 00:02:35,729 --> 00:02:32,190 important for us understanding how life 52 00:02:38,610 --> 00:02:35,739 utilizes pigments not just for using 53 00:02:39,360 --> 00:02:38,620 metabolism for for taking energy from a 54 00:02:42,990 --> 00:02:39,370 star 55 00:02:45,869 --> 00:02:43,000 to grow but also to protect the cells 56 00:02:47,610 --> 00:02:45,879 from ionizing radiation from ultraviolet 57 00:02:49,080 --> 00:02:47,620 radiation and so this is a really 58 00:02:49,910 --> 00:02:49,090 important area of study for us in 59 00:02:52,830 --> 00:02:49,920 astrobiology 60 00:02:55,259 --> 00:02:52,840 now this month we have our winner was 61 00:02:58,589 --> 00:02:55,269 Andre on tunics who goes by at 62 00:03:00,180 --> 00:02:58,599 extremophiles UK on Twitter but we also 63 00:03:02,789 --> 00:03:00,190 want to give a special shout-out this 64 00:03:05,670 --> 00:03:02,799 month to Maryanne Denton and Victor 65 00:03:07,440 --> 00:03:05,680 Baron oov for creating a fun little play 66 00:03:10,860 --> 00:03:07,450 on words for the men at work song land 67 00:03:13,920 --> 00:03:10,870 down under now bear with me here it 68 00:03:17,220 --> 00:03:13,930 comes from a land down under where it 69 00:03:19,759 --> 00:03:17,230 licks glow and plankton blunder can't 70 00:03:23,699 --> 00:03:19,769 you hear can't you hear that thunder 71 00:03:25,559 --> 00:03:23,709 down to Lake Hillier so I know I'm not a 72 00:03:27,630 --> 00:03:25,569 great singer but you guys get the point 73 00:03:29,160 --> 00:03:27,640 there it's pretty awesome maybe in the 74 00:03:31,890 --> 00:03:29,170 future for asking astrobiologists we'll 75 00:03:35,099 --> 00:03:31,900 create our own soundtrack of song covers 76 00:03:36,960 --> 00:03:35,109 with astrobiology lyrics who knows we 77 00:03:39,210 --> 00:03:36,970 also have some awesome ambassadors of 78 00:03:41,369 --> 00:03:39,220 the month to share with you just like 79 00:03:43,440 --> 00:03:41,379 last month we decided to name four 80 00:03:45,930 --> 00:03:43,450 ambassadors this month and so many of 81 00:03:48,569 --> 00:03:45,940 you are sharing and retweeting and 82 00:03:50,220 --> 00:03:48,579 liking and commenting and engaging and 83 00:03:51,900 --> 00:03:50,230 and getting the word out about our show 84 00:03:53,729 --> 00:03:51,910 about the awesome work the 85 00:03:55,920 --> 00:03:53,739 astrobiologists do who come on the show 86 00:03:57,930 --> 00:03:55,930 with us so this month we want to 87 00:04:00,539 --> 00:03:57,940 celebrate four of you as our ambassadors 88 00:04:03,539 --> 00:04:00,549 of the month the four of you are MonaVie 89 00:04:04,589 --> 00:04:03,549 Kaukauna at MonaVie queque who I have to 90 00:04:06,780 --> 00:04:04,599 just started talking to through 91 00:04:08,520 --> 00:04:06,790 Instagram about her career in 92 00:04:11,069 --> 00:04:08,530 astrobiology and things that she's 93 00:04:15,479 --> 00:04:11,079 really into awesome Dallara 94 00:04:17,430 --> 00:04:15,489 kill Carson at Dobie dela Dallara is a 95 00:04:19,259 --> 00:04:17,440 graduate student in South Korea who's 96 00:04:21,360 --> 00:04:19,269 been working in the realm of 97 00:04:23,400 --> 00:04:21,370 astrobiology and is really interested in 98 00:04:26,129 --> 00:04:23,410 being involved in that career field we 99 00:04:29,610 --> 00:04:26,139 also have a zoo Lupino ba at as well 100 00:04:31,200 --> 00:04:29,620 Pino Bob as well as ESMA on Twitter at 101 00:04:34,080 --> 00:04:31,210 Astro as mala gist 102 00:04:35,790 --> 00:04:34,090 ESMA is actually just join me this 103 00:04:38,400 --> 00:04:35,800 summer in the blue marble space young 104 00:04:39,719 --> 00:04:38,410 scientist program she'll be working with 105 00:04:42,570 --> 00:04:39,729 me for the Center for life detection 106 00:04:45,240 --> 00:04:42,580 Sciences at NASA Ames on a project 107 00:04:46,800 --> 00:04:45,250 studying bio signatures and how we can 108 00:04:49,529 --> 00:04:46,810 use our knowledge of bio signatures to 109 00:04:51,910 --> 00:04:49,539 look for life beyond the earth so with 110 00:04:53,650 --> 00:04:51,920 all of that said I'm super excited 111 00:04:56,440 --> 00:04:53,660 this episode it's gonna be a lot of fun 112 00:04:59,170 --> 00:04:56,450 guys so please help me welcome to our 113 00:05:01,480 --> 00:04:59,180 show dr. Eddie sweet ermine hi Eddie 114 00:05:03,490 --> 00:05:01,490 hi Graham thank you so much for having 115 00:05:05,590 --> 00:05:03,500 me here and thank you to say Gannett and 116 00:05:07,540 --> 00:05:05,600 the NASA Astrobiology Institute 117 00:05:09,370 --> 00:05:07,550 I mean it's so great to have you on the 118 00:05:10,930 --> 00:05:09,380 show we wanted to have you on for a long 119 00:05:14,080 --> 00:05:10,940 time now talk about some of your work 120 00:05:17,730 --> 00:05:14,090 you've been prolific of like publishing 121 00:05:19,950 --> 00:05:17,740 so much awesome research in the realm is 122 00:05:22,900 --> 00:05:19,960 computational modeling to understand 123 00:05:24,840 --> 00:05:22,910 exoplanets to look for bio signatures 124 00:05:27,130 --> 00:05:24,850 what things might be false positives 125 00:05:29,260 --> 00:05:27,140 false negatives there's so much cool 126 00:05:31,450 --> 00:05:29,270 work you're doing and I definitely want 127 00:05:33,220 --> 00:05:31,460 to talk about a lot of that with you but 128 00:05:34,390 --> 00:05:33,230 before we get to that point since we do 129 00:05:36,700 --> 00:05:34,400 have a lot of folks who watch the show 130 00:05:38,920 --> 00:05:36,710 who are you know high school students or 131 00:05:40,510 --> 00:05:38,930 undergraduate collegiate students it's 132 00:05:43,480 --> 00:05:40,520 always nice for them to hear about the 133 00:05:45,220 --> 00:05:43,490 pathways that bring astrobiologists kind 134 00:05:46,780 --> 00:05:45,230 of forward in their careers and I'm 135 00:05:48,940 --> 00:05:46,790 curious if you could share with us kind 136 00:05:51,160 --> 00:05:48,950 of your your science origin story if you 137 00:05:52,170 --> 00:05:51,170 will what really got you kind of into 138 00:05:54,190 --> 00:05:52,180 this realm of wanting to become 139 00:05:56,500 --> 00:05:54,200 scientist and someone who works in this 140 00:05:57,670 --> 00:05:56,510 realm of exoplanets yeah that's that's a 141 00:05:59,050 --> 00:05:57,680 great question something I think about a 142 00:06:00,580 --> 00:05:59,060 lot you know my parents are really 143 00:06:02,740 --> 00:06:00,590 helpful in cultivating an interest in 144 00:06:03,850 --> 00:06:02,750 science with me like many kids I love 145 00:06:06,850 --> 00:06:03,860 dinosaurs 146 00:06:08,800 --> 00:06:06,860 I mean dinosaur books and I spent so 147 00:06:10,390 --> 00:06:08,810 much time with them even further than 148 00:06:12,850 --> 00:06:10,400 that my dad would take my sister and I 149 00:06:14,830 --> 00:06:12,860 out fossil hunting and so we drink dig 150 00:06:16,780 --> 00:06:14,840 up trilobite sand fossilized coral and 151 00:06:18,250 --> 00:06:16,790 I'd spend some time as the kid imagining 152 00:06:22,210 --> 00:06:18,260 what those places look like you know 153 00:06:25,510 --> 00:06:22,220 hundreds of years ago and and and 154 00:06:27,490 --> 00:06:25,520 somewhat you know naively well I had 155 00:06:28,990 --> 00:06:27,500 wanted to become a paleontologist I 156 00:06:31,570 --> 00:06:29,000 thought as a kid that by the time I got 157 00:06:33,520 --> 00:06:31,580 old enough that all the dinosaur bones 158 00:06:36,070 --> 00:06:33,530 would have been dug it dug up that all 159 00:06:38,080 --> 00:06:36,080 the fossils would have been gone which 160 00:06:40,030 --> 00:06:38,090 is not what not that that won't happen 161 00:06:43,150 --> 00:06:40,040 so if you want to be a paleontologist 162 00:06:44,710 --> 00:06:43,160 don't let that dissuade you but I also 163 00:06:47,140 --> 00:06:44,720 got interested in astronomy I bought my 164 00:06:49,390 --> 00:06:47,150 first telescope in high school I saw the 165 00:06:51,340 --> 00:06:49,400 transit of Venus in 2004 and I thought 166 00:06:55,800 --> 00:06:51,350 you know as that little disc of Venus 167 00:06:57,490 --> 00:06:55,810 went across the Sun you know what other 168 00:06:59,590 --> 00:06:57,500 civilizations are out there watching 169 00:07:01,870 --> 00:06:59,600 their planets watching our planet 170 00:07:03,310 --> 00:07:01,880 transit it's Sun you know and and that 171 00:07:04,580 --> 00:07:03,320 got me thinking about how vast the 172 00:07:06,290 --> 00:07:04,590 universe is and how there's 173 00:07:08,810 --> 00:07:06,300 much out there that no matter how many 174 00:07:10,730 --> 00:07:08,820 lifetimes you live you live there be so 175 00:07:12,770 --> 00:07:10,740 much more to explore and so much more to 176 00:07:15,980 --> 00:07:12,780 discover and so that's really what got 177 00:07:17,690 --> 00:07:15,990 me interested in in astronomy and then I 178 00:07:19,790 --> 00:07:17,700 went to the University of Washington in 179 00:07:21,740 --> 00:07:19,800 Seattle for graduate school we're with 180 00:07:23,510 --> 00:07:21,750 dr. Victoria Meadows who's head of the 181 00:07:25,880 --> 00:07:23,520 virtual planetary laboratory and that's 182 00:07:28,450 --> 00:07:25,890 really where I first started learning 183 00:07:32,120 --> 00:07:28,460 about every mod in planetary atmospheres 184 00:07:34,130 --> 00:07:32,130 professor next month at UC Riverside to 185 00:07:36,650 --> 00:07:34,140 continue this work on bio signatures and 186 00:07:38,210 --> 00:07:36,660 habitability that's awesome and I can 187 00:07:40,010 --> 00:07:38,220 Congrats and starting the new assistant 188 00:07:41,030 --> 00:07:40,020 professorship that's that's great I look 189 00:07:42,920 --> 00:07:41,040 forward to all the stuff you can be 190 00:07:44,240 --> 00:07:42,930 doing there it's really cool to start 191 00:07:47,600 --> 00:07:44,250 off the kind of that the dinosaur bone 192 00:07:49,700 --> 00:07:47,610 kind of I love that figure where you see 193 00:07:51,380 --> 00:07:49,710 it's like knowledge of dinosaurs through 194 00:07:52,880 --> 00:07:51,390 time of your life and like you're a kid 195 00:07:54,410 --> 00:07:52,890 you know everything about dinosaurs and 196 00:07:55,820 --> 00:07:54,420 then you lose it unless you become a 197 00:07:57,530 --> 00:07:55,830 paleontologist and then you get it back 198 00:08:00,050 --> 00:07:57,540 again I think for a lot of us it's a 199 00:08:02,810 --> 00:08:00,060 huge pathway is because dinosaurs are so 200 00:08:04,220 --> 00:08:02,820 cool but yeah so for everyone watching I 201 00:08:06,740 --> 00:08:04,230 mean there's lots of pathways to get 202 00:08:08,480 --> 00:08:06,750 into astrobiology dr. speedermen had a 203 00:08:10,460 --> 00:08:08,490 really incredible pathway as well and 204 00:08:11,840 --> 00:08:10,470 now he's gonna be a professor sharing 205 00:08:13,460 --> 00:08:11,850 his knowledge with other students who 206 00:08:15,080 --> 00:08:13,470 are coming up and learning about 207 00:08:19,250 --> 00:08:15,090 astrobiology and astronomy and 208 00:08:22,130 --> 00:08:19,260 astrophysics so it's very cool much like 209 00:08:24,490 --> 00:08:22,140 me you you were born at a time when we 210 00:08:27,830 --> 00:08:24,500 had no confirmations of any exoplanets 211 00:08:30,200 --> 00:08:27,840 so so for you as a scientist but also 212 00:08:31,940 --> 00:08:30,210 just as a person how what's it been like 213 00:08:34,520 --> 00:08:31,950 for you someone really interested with a 214 00:08:36,890 --> 00:08:34,530 lot of knowledge as we've been to more 215 00:08:39,110 --> 00:08:36,900 and more hundreds and thousands of 216 00:08:40,670 --> 00:08:39,120 exoplanets what's that experience been 217 00:08:43,250 --> 00:08:40,680 like for you since that's really what's 218 00:08:45,260 --> 00:08:43,260 intriguing you a lot yeah I mean I think 219 00:08:46,880 --> 00:08:45,270 I think you know you're absolutely right 220 00:08:49,880 --> 00:08:46,890 the first exoplanet around a sun-like 221 00:08:51,590 --> 00:08:49,890 star wasn't discovered in 1995 and 222 00:08:52,940 --> 00:08:51,600 before then you know it was somewhat 223 00:08:54,740 --> 00:08:52,950 speculative to think about planets 224 00:08:57,020 --> 00:08:54,750 around other stars but of course we knew 225 00:08:59,600 --> 00:08:57,030 that in our solar system we had you know 226 00:09:01,970 --> 00:08:59,610 at the time nine planets now we we say 227 00:09:03,860 --> 00:09:01,980 they're eight planets and we knew that 228 00:09:06,050 --> 00:09:03,870 the processes that happened in our own 229 00:09:08,660 --> 00:09:06,060 solar system probably happened elsewhere 230 00:09:10,550 --> 00:09:08,670 and I think this is often you know 231 00:09:12,620 --> 00:09:10,560 something that that astrobiologists rely 232 00:09:14,480 --> 00:09:12,630 on is this universality of physics and 233 00:09:17,280 --> 00:09:14,490 chemistry and then we hope that there's 234 00:09:18,660 --> 00:09:17,290 also a universality of biology that 235 00:09:21,030 --> 00:09:18,670 you know chem that biology is sort of 236 00:09:22,590 --> 00:09:21,040 derived chemistry and therefore if the 237 00:09:25,850 --> 00:09:22,600 same initial conditions happen somewhere 238 00:09:28,350 --> 00:09:25,860 else then we'd expect a similar result 239 00:09:30,210 --> 00:09:28,360 and so I think I think getting the 240 00:09:32,759 --> 00:09:30,220 confirmation that there are so many 241 00:09:34,800 --> 00:09:32,769 exoplanets out there you know is sort of 242 00:09:36,660 --> 00:09:34,810 a confirmation of this you know 243 00:09:38,970 --> 00:09:36,670 Copernican principle that you know the 244 00:09:43,620 --> 00:09:38,980 earth well it is a special place to us 245 00:09:45,660 --> 00:09:43,630 maybe isn't the only only example of a 246 00:09:47,790 --> 00:09:45,670 place that's potentially habitable and 247 00:09:49,710 --> 00:09:47,800 maybe inhabited and that our solar 248 00:09:51,809 --> 00:09:49,720 system is full of all these other 249 00:09:54,629 --> 00:09:51,819 planets but that there are similar 250 00:09:55,590 --> 00:09:54,639 planets else and in fact planets types 251 00:09:57,420 --> 00:09:55,600 of planets that we never would have 252 00:09:59,189 --> 00:09:57,430 imagined we're discovering you know the 253 00:10:00,809 --> 00:09:59,199 most common type of planet is actually a 254 00:10:01,829 --> 00:10:00,819 planet that's in between the size of the 255 00:10:04,079 --> 00:10:01,839 earth and the size of Neptune that 256 00:10:08,160 --> 00:10:04,089 wasn't expected and so we're learning a 257 00:10:09,930 --> 00:10:08,170 lot and we're also sort of discovering 258 00:10:12,449 --> 00:10:09,940 that you know what we thought might be 259 00:10:14,939 --> 00:10:12,459 rare isn't on the other hand we have to 260 00:10:16,920 --> 00:10:14,949 humble ourselves in knowing that just 261 00:10:19,139 --> 00:10:16,930 because we think that or hope that life 262 00:10:20,999 --> 00:10:19,149 is common doesn't necessarily mean it's 263 00:10:23,490 --> 00:10:21,009 true we've got to go and look hmm 264 00:10:25,290 --> 00:10:23,500 yeah no kidding so so could you for our 265 00:10:27,900 --> 00:10:25,300 audience maybe explain the process of 266 00:10:29,519 --> 00:10:27,910 looking at an exoplanet and specifically 267 00:10:31,559 --> 00:10:29,529 looking for bio signatures for signs of 268 00:10:33,269 --> 00:10:31,569 life in an exoplanet what does that 269 00:10:34,829 --> 00:10:33,279 require what are we actually looking for 270 00:10:36,540 --> 00:10:34,839 or looking at when we're doing that 271 00:10:38,730 --> 00:10:36,550 right it's important to remember that 272 00:10:40,920 --> 00:10:38,740 right now at this moment we're not 273 00:10:43,949 --> 00:10:40,930 analyzing exoplanet atmospheres for bio 274 00:10:46,949 --> 00:10:43,959 signatures we've detected molecules in 275 00:10:49,199 --> 00:10:46,959 large planets plans the size of Jupiter 276 00:10:51,840 --> 00:10:49,209 and the size of Neptune and individual 277 00:10:53,370 --> 00:10:51,850 gaseous molecules earth sized planets 278 00:10:55,650 --> 00:10:53,380 are smaller and they're harder to 279 00:10:58,019 --> 00:10:55,660 characterize and so we're really talking 280 00:11:00,720 --> 00:10:58,029 about future technology that's within 281 00:11:05,189 --> 00:11:00,730 many of our lifetimes but not right this 282 00:11:06,960 --> 00:11:05,199 second and what we look for is is signs 283 00:11:09,629 --> 00:11:06,970 that the environment has been changed by 284 00:11:12,030 --> 00:11:09,639 life and so one example that we often go 285 00:11:14,040 --> 00:11:12,040 to on earth that that represents huge 286 00:11:15,480 --> 00:11:14,050 monumental change in our planetary 287 00:11:17,220 --> 00:11:15,490 chemistry in our planetary atmosphere 288 00:11:18,960 --> 00:11:17,230 from life is the oxygen or atmosphere 289 00:11:22,139 --> 00:11:18,970 that we we breathe we need it to breathe 290 00:11:24,480 --> 00:11:22,149 and this oxygen came from in part 291 00:11:26,280 --> 00:11:24,490 photosynthetic life without the 292 00:11:28,230 --> 00:11:26,290 photosynthetic life taking carbon 293 00:11:30,680 --> 00:11:28,240 dioxide and water and energy from our 294 00:11:34,250 --> 00:11:30,690 Sun and creating oxygen 295 00:11:37,220 --> 00:11:34,260 and and an organic matter that oxygen 296 00:11:39,470 --> 00:11:37,230 atmosphere wouldn't exist and so oxygen 297 00:11:41,960 --> 00:11:39,480 is one signature potentially of life and 298 00:11:43,880 --> 00:11:41,970 the way that we can find it is the way 299 00:11:45,620 --> 00:11:43,890 that the oxygen molecule interacts with 300 00:11:47,420 --> 00:11:45,630 light so as light either passes through 301 00:11:49,790 --> 00:11:47,430 an atmosphere or scattered by the 302 00:11:51,980 --> 00:11:49,800 atmosphere certain wavelengths of light 303 00:11:54,860 --> 00:11:51,990 are absorbed by that oxygen molecule and 304 00:11:56,690 --> 00:11:54,870 certain ones are are scattered or 305 00:11:58,670 --> 00:11:56,700 transmitted through the atmosphere and 306 00:12:00,710 --> 00:11:58,680 by looking for that missing light we can 307 00:12:02,180 --> 00:12:00,720 infer the presence of say the oxygen 308 00:12:03,530 --> 00:12:02,190 molecule and there are other molecules 309 00:12:05,840 --> 00:12:03,540 that are like that we'd like to see 310 00:12:07,580 --> 00:12:05,850 oxygen perhaps methane because methane 311 00:12:08,900 --> 00:12:07,590 is also produced by life and together 312 00:12:10,820 --> 00:12:08,910 there in this what we call 313 00:12:13,160 --> 00:12:10,830 disequilibrium and that is if you left 314 00:12:15,740 --> 00:12:13,170 them alone they would react together and 315 00:12:17,960 --> 00:12:15,750 and the less abundant molecule would 316 00:12:19,670 --> 00:12:17,970 disappear but because both have active 317 00:12:21,740 --> 00:12:19,680 sources on earth due to life that 318 00:12:23,540 --> 00:12:21,750 creates a chemical district equilibrium 319 00:12:25,250 --> 00:12:23,550 in the atmosphere both interact with 320 00:12:27,440 --> 00:12:25,260 light in specific ways that could be 321 00:12:28,520 --> 00:12:27,450 inferred from by a remote observer so 322 00:12:30,830 --> 00:12:28,530 that's really what we're talking about 323 00:12:32,270 --> 00:12:30,840 when we talk about bio signatures that's 324 00:12:33,590 --> 00:12:32,280 incredible yeah and I think a lot of 325 00:12:35,450 --> 00:12:33,600 people that they talk a lot you know and 326 00:12:38,060 --> 00:12:35,460 I have just general conversations about 327 00:12:39,470 --> 00:12:38,070 looking at an exoplanet atmosphere for a 328 00:12:42,110 --> 00:12:39,480 sign of life a lot of people bring up 329 00:12:45,080 --> 00:12:42,120 oxygen right away but you've also done a 330 00:12:47,570 --> 00:12:45,090 lot of work in this issue of the false 331 00:12:48,920 --> 00:12:47,580 positives and even false negatives when 332 00:12:50,570 --> 00:12:48,930 we're when we start using some of these 333 00:12:52,760 --> 00:12:50,580 next-generation telescopes to look at 334 00:12:54,560 --> 00:12:52,770 these atmospheres could you speak for a 335 00:12:56,630 --> 00:12:54,570 bit to our audience about like what 336 00:12:58,910 --> 00:12:56,640 false positive signs would be what false 337 00:13:00,710 --> 00:12:58,920 negative signs would be and how we can 338 00:13:01,520 --> 00:13:00,720 best you know kind of muddle through 339 00:13:04,060 --> 00:13:01,530 figuring that out 340 00:13:07,280 --> 00:13:04,070 yeah that's that's a great question so 341 00:13:09,950 --> 00:13:07,290 so oxygen in our atmosphere is almost 342 00:13:13,700 --> 00:13:09,960 entirely created by plants and algae and 343 00:13:15,770 --> 00:13:13,710 cyanobacteria so life but we've got to 344 00:13:16,760 --> 00:13:15,780 be really quite sure that the oxygen we 345 00:13:18,440 --> 00:13:16,770 find in an exoplanet atmospheres 346 00:13:21,290 --> 00:13:18,450 actually due to that process not 347 00:13:23,150 --> 00:13:21,300 something else and so one possibility is 348 00:13:25,610 --> 00:13:23,160 that there are photochemical processes 349 00:13:27,290 --> 00:13:25,620 that generate the generate oxygen one 350 00:13:30,110 --> 00:13:27,300 example that sort of close to home is 351 00:13:31,910 --> 00:13:30,120 Mars Mars has a very thin co2 atmosphere 352 00:13:33,860 --> 00:13:31,920 it's cold it doesn't have a lot of water 353 00:13:36,290 --> 00:13:33,870 in it and those conditions mean that 354 00:13:38,780 --> 00:13:36,300 that that co2 in the atmosphere some of 355 00:13:41,160 --> 00:13:38,790 it gets broken apart into oxygen and 356 00:13:44,549 --> 00:13:41,170 carbon monoxide some of those ox 357 00:13:46,139 --> 00:13:44,559 atoms combine into oxygen molecules some 358 00:13:48,269 --> 00:13:46,149 of them form ozone and that's actually 359 00:13:50,789 --> 00:13:48,279 remotely detectable on earth we can see 360 00:13:53,249 --> 00:13:50,799 these small amounts of ozone and oxygen 361 00:13:55,559 --> 00:13:53,259 and Mars atmosphere and we wouldn't 362 00:13:57,479 --> 00:13:55,569 mistake that necessarily because of all 363 00:13:58,349 --> 00:13:57,489 the conditions I mentioned they're very 364 00:13:59,939 --> 00:13:58,359 different from Earth we necessarily 365 00:14:01,949 --> 00:13:59,949 mistake that for life but it does hop 366 00:14:03,539 --> 00:14:01,959 but the Dutch tell us that there are 367 00:14:05,789 --> 00:14:03,549 processes that can generate oxygen 368 00:14:08,249 --> 00:14:05,799 abiotic ly and they might be very 369 00:14:09,809 --> 00:14:08,259 different if the star that the planets 370 00:14:12,239 --> 00:14:09,819 orbiting is very different and the 371 00:14:14,340 --> 00:14:12,249 chemistry is driven in large part by the 372 00:14:16,139 --> 00:14:14,350 ultraviolet radiation from the star so 373 00:14:19,259 --> 00:14:16,149 you alter the ultraviolet radiation from 374 00:14:21,229 --> 00:14:19,269 the star then you can alter the the 375 00:14:24,389 --> 00:14:21,239 chemical pathways that can generate 376 00:14:26,489 --> 00:14:24,399 oxygen from carbon dioxide or ozone from 377 00:14:27,629 --> 00:14:26,499 that oxygen and carbon dioxide and so 378 00:14:29,970 --> 00:14:27,639 you have got to be very careful in 379 00:14:32,549 --> 00:14:29,980 teasing out those effects another 380 00:14:34,650 --> 00:14:32,559 example potentially is that you could 381 00:14:36,599 --> 00:14:34,660 lose a lot of water we know that for 382 00:14:38,369 --> 00:14:36,609 example Venus is an example of a planet 383 00:14:38,729 --> 00:14:38,379 close to home must have lost a lot of 384 00:14:41,039 --> 00:14:38,739 water 385 00:14:44,729 --> 00:14:41,049 dude it's DT reom to hydrogen ratio in 386 00:14:47,240 --> 00:14:44,739 the atmosphere and what happened what 387 00:14:49,670 --> 00:14:47,250 must have happened is the heavier 388 00:14:51,470 --> 00:14:49,680 like on Venus we don't have any free 389 00:14:55,270 --> 00:14:51,480 oxygen left except for a tiny amount 390 00:14:58,310 --> 00:14:55,280 like on Mars but but some speculated 391 00:15:00,800 --> 00:14:58,320 enough water and you have a robust 392 00:15:02,240 --> 00:15:00,810 runaway process where you're losing a 393 00:15:04,370 --> 00:15:02,250 lot of hydrogen and leaving oxygen 394 00:15:07,670 --> 00:15:04,380 behind that you could oxidize the planet 395 00:15:09,050 --> 00:15:07,680 so heavily that behind enough oxygen 396 00:15:10,310 --> 00:15:09,060 that it builds up in the atmosphere and 397 00:15:12,530 --> 00:15:10,320 that would represent another false 398 00:15:13,970 --> 00:15:12,540 positive for oxygen that's not due to 399 00:15:16,670 --> 00:15:13,980 biology but in fact doing an abiotic 400 00:15:18,770 --> 00:15:16,680 planetary process and so we don't know 401 00:15:20,990 --> 00:15:18,780 how common that is but again we have to 402 00:15:22,580 --> 00:15:21,000 look and our models show that it's 403 00:15:24,500 --> 00:15:22,590 plausible so it's something that we have 404 00:15:25,790 --> 00:15:24,510 to worry about and we think about ways 405 00:15:27,680 --> 00:15:25,800 to get around that one of the ways to 406 00:15:29,090 --> 00:15:27,690 get around that is to look for this 407 00:15:30,530 --> 00:15:29,100 disequilibrium signature that I 408 00:15:32,180 --> 00:15:30,540 mentioned so if you had an abiotic 409 00:15:35,360 --> 00:15:32,190 oxygen atmosphere you would not expect 410 00:15:37,940 --> 00:15:35,370 these pounds like methane to be present 411 00:15:40,430 --> 00:15:37,950 or nitrous oxide which is another 412 00:15:42,050 --> 00:15:40,440 potential gaseous bio signature so we 413 00:15:43,400 --> 00:15:42,060 want to look at a combination of things 414 00:15:46,460 --> 00:15:43,410 and we want to look at the context of 415 00:15:48,230 --> 00:15:46,470 the of the environment if we saw 20% 416 00:15:50,360 --> 00:15:48,240 oxygen on the one bar atmosphere around 417 00:15:53,120 --> 00:15:50,370 a sun-like star that would be a pretty 418 00:15:53,750 --> 00:15:53,130 pretty compelling indicator of life on 419 00:15:56,420 --> 00:15:53,760 that planet 420 00:15:58,940 --> 00:15:56,430 you also mentioned false negatives and 421 00:16:00,880 --> 00:15:58,950 so that would be for example the half of 422 00:16:03,829 --> 00:16:00,890 Earth history that had no oxygen at all 423 00:16:05,750 --> 00:16:03,839 and so we know that in in in the in the 424 00:16:07,130 --> 00:16:05,760 Archaean Eon which lasted from four 425 00:16:08,690 --> 00:16:07,140 billion years ago to two-and-a-half 426 00:16:10,070 --> 00:16:08,700 billion years ago there was very little 427 00:16:12,710 --> 00:16:10,080 free oxygen in our atmosphere yet there 428 00:16:16,280 --> 00:16:12,720 was microbial life it was generating 429 00:16:18,230 --> 00:16:16,290 methane but not oxygen and so some have 430 00:16:19,970 --> 00:16:18,240 speculated that if we look or and 431 00:16:22,130 --> 00:16:19,980 modeled that if we we look at the 432 00:16:23,960 --> 00:16:22,140 methane to carbon dioxide ratio in that 433 00:16:26,600 --> 00:16:23,970 atmosphere that would be indicative of a 434 00:16:29,240 --> 00:16:26,610 metabolic process that's taking co2 but 435 00:16:32,350 --> 00:16:29,250 hydrogen and methane which very 436 00:16:34,910 --> 00:16:32,360 primitive microbial metabolism hurts do 437 00:16:39,260 --> 00:16:34,920 we believe in the in the deep geologic 438 00:16:40,970 --> 00:16:39,270 past so that's kind of a flavor of this 439 00:16:43,010 --> 00:16:40,980 false negative and false positive issue 440 00:16:45,829 --> 00:16:43,020 it's looking looking at the context and 441 00:16:48,500 --> 00:16:45,839 we need not just astronomers and 442 00:16:50,630 --> 00:16:48,510 biologists but also chemists and 443 00:16:52,940 --> 00:16:50,640 geochemists and Atmospheric scientists 444 00:16:54,870 --> 00:16:52,950 to put all of this together to kind of 445 00:16:57,130 --> 00:16:54,880 give us our best shot of 446 00:17:00,550 --> 00:16:57,140 recognizing a habitable and inhabited 447 00:17:04,809 --> 00:17:00,560 planet so Eddie this user on Twitter 448 00:17:07,390 --> 00:17:04,819 Rick Ward at our Jay Ward 1775 had asked 449 00:17:08,860 --> 00:17:07,400 this really interesting question posting 450 00:17:11,770 --> 00:17:08,870 on the people of space Twitter account 451 00:17:14,049 --> 00:17:11,780 he wanted to know would it be safe to 452 00:17:15,939 --> 00:17:14,059 say that the earlier you go in the 453 00:17:17,679 --> 00:17:15,949 geological record here on earth that the 454 00:17:20,110 --> 00:17:17,689 less certain the less certainty you'd 455 00:17:23,049 --> 00:17:20,120 have if you were an extraterrestrial 456 00:17:25,500 --> 00:17:23,059 species watching us from afar that there 457 00:17:28,210 --> 00:17:25,510 actually is life on this little rock 458 00:17:30,280 --> 00:17:28,220 yeah that's a that's a great question 459 00:17:32,710 --> 00:17:30,290 one way to answer that is to think about 460 00:17:34,919 --> 00:17:32,720 how much biomass has existed on on earth 461 00:17:37,240 --> 00:17:34,929 you know through time we think the first 462 00:17:39,790 --> 00:17:37,250 metabolisms were chemosynthetic that is 463 00:17:42,310 --> 00:17:39,800 they took an existing energy gradient 464 00:17:45,669 --> 00:17:42,320 and then they utilize that energy 465 00:17:47,799 --> 00:17:45,679 gradient for for for for metabolic 466 00:17:49,780 --> 00:17:47,809 processes and that would be very hard to 467 00:17:51,880 --> 00:17:49,790 detect remotely and maybe impossible and 468 00:17:53,799 --> 00:17:51,890 then we had photosynthesis that didn't 469 00:17:55,240 --> 00:17:53,809 generate oxygen called anoxygenic 470 00:17:58,000 --> 00:17:55,250 photosynthesis and that may have 471 00:18:00,000 --> 00:17:58,010 generated a signature there's also 472 00:18:02,080 --> 00:18:00,010 managed an assist which does not require 473 00:18:04,650 --> 00:18:02,090 photosynthesis and so perhaps we could 474 00:18:08,410 --> 00:18:04,660 have seen those types of metabolisms on 475 00:18:11,230 --> 00:18:08,420 on early Earth but but it's absolutely 476 00:18:13,540 --> 00:18:11,240 true that that oxygen 'ok photosynthesis 477 00:18:16,060 --> 00:18:13,550 because it generates so much energy and 478 00:18:18,130 --> 00:18:16,070 therefore can support so much more 479 00:18:21,700 --> 00:18:18,140 biomass that would be an easier thing to 480 00:18:24,549 --> 00:18:21,710 see remotely than then the more 481 00:18:26,440 --> 00:18:24,559 primitive metabolisms but we don't know 482 00:18:29,310 --> 00:18:26,450 the extent to which that is true we 483 00:18:32,380 --> 00:18:29,320 think that there are potentially 484 00:18:34,780 --> 00:18:32,390 atmospheric indicators in the carbon 485 00:18:36,910 --> 00:18:34,790 bearing molecules so if we looked at 486 00:18:39,669 --> 00:18:36,920 carbon dioxide and methane and carbon 487 00:18:42,100 --> 00:18:39,679 monoxide that that a primitive 488 00:18:44,200 --> 00:18:42,110 metabolism that can do methanogenesis 489 00:18:47,410 --> 00:18:44,210 would change the ratios of those gases 490 00:18:49,540 --> 00:18:47,420 in such a way as to be inferable that 491 00:18:51,220 --> 00:18:49,550 that is a bio signature mm-hmm 492 00:18:52,750 --> 00:18:51,230 interesting yeah I mean so it's kind of 493 00:18:54,340 --> 00:18:52,760 cool to think about you know alien life 494 00:18:57,040 --> 00:18:54,350 watching us from afar and how they may 495 00:18:58,750 --> 00:18:57,050 or may not have detected us I often 496 00:19:00,370 --> 00:18:58,760 times have told people that you know 497 00:19:02,200 --> 00:19:00,380 we're never going to know specifically 498 00:19:04,360 --> 00:19:02,210 how life started on earth you know just 499 00:19:05,860 --> 00:19:04,370 too much unknown there but wouldn't it 500 00:19:07,500 --> 00:19:05,870 be cool if there were aliens out there 501 00:19:10,710 --> 00:19:07,510 watching us from afar who had 502 00:19:13,290 --> 00:19:10,720 some knowledge of what happened here and 503 00:19:16,650 --> 00:19:13,300 you have a paper titled a limited 504 00:19:19,320 --> 00:19:16,660 habitable zone for complex life and in 505 00:19:21,570 --> 00:19:19,330 this paper you discuss the issues with 506 00:19:23,550 --> 00:19:21,580 the idea of the habitable zone the 507 00:19:25,440 --> 00:19:23,560 Goldilocks zone in this region around a 508 00:19:28,500 --> 00:19:25,450 star where liquid water can exist in the 509 00:19:30,480 --> 00:19:28,510 surface of a planet based on the amount 510 00:19:32,490 --> 00:19:30,490 of star light as well that planet is 511 00:19:34,530 --> 00:19:32,500 receiving it turns out that some of 512 00:19:36,900 --> 00:19:34,540 these these habitable zone areas might 513 00:19:38,430 --> 00:19:36,910 actually not be habitable could you 514 00:19:40,320 --> 00:19:38,440 speak to that and tell us you know kind 515 00:19:42,420 --> 00:19:40,330 of what the interpretation was from the 516 00:19:44,130 --> 00:19:42,430 from those results yeah I mean I think I 517 00:19:46,500 --> 00:19:44,140 think so the habitable zone originally 518 00:19:48,770 --> 00:19:46,510 as a concept is is is focused on liquid 519 00:19:51,450 --> 00:19:48,780 water surface liquid water and a 520 00:19:55,050 --> 00:19:51,460 prerequisite for life and I think that 521 00:19:57,240 --> 00:19:55,060 you know that's a good paradigm for 522 00:20:01,080 --> 00:19:57,250 microbial life for simple for simple 523 00:20:02,580 --> 00:20:01,090 life and you have to think about the 524 00:20:05,310 --> 00:20:02,590 habitable zone is how it's that's how 525 00:20:07,620 --> 00:20:05,320 it's calculated often is to assume at 526 00:20:10,470 --> 00:20:07,630 the dominant greenhouse gas is co2 and 527 00:20:12,090 --> 00:20:10,480 so the closer you are to the star the 528 00:20:14,100 --> 00:20:12,100 less co2 you need and the further from 529 00:20:15,630 --> 00:20:14,110 the star the more co2 you need and we 530 00:20:16,980 --> 00:20:15,640 believe that the process that regulates 531 00:20:18,720 --> 00:20:16,990 how much co2 in the atmosphere are 532 00:20:20,310 --> 00:20:18,730 similar to that of the earth which is 533 00:20:22,500 --> 00:20:20,320 the carbonate silicates cycle and this 534 00:20:25,229 --> 00:20:22,510 is a process that's been posited for the 535 00:20:27,269 --> 00:20:25,239 last four 536 00:20:29,129 --> 00:20:27,279 Earth's habitability through time as the 537 00:20:32,489 --> 00:20:29,139 Sun has actually started off much dimmer 538 00:20:35,099 --> 00:20:32,499 and brighter in geologic time we believe 539 00:20:37,609 --> 00:20:35,109 the co2 in the in our atmosphere started 540 00:20:40,739 --> 00:20:37,619 off high and has been drawn down as 541 00:20:43,229 --> 00:20:40,749 weathering rates have became as the Sun 542 00:20:45,089 --> 00:20:43,239 got rubbed some got brighter well if you 543 00:20:46,919 --> 00:20:45,099 think about the habitable zone as it 544 00:20:49,259 --> 00:20:46,929 exists if you were to place an 545 00:20:50,879 --> 00:20:49,269 earth-like planet at the outer edge of 546 00:20:52,469 --> 00:20:50,889 the hapless honest it's currently 547 00:20:54,629 --> 00:20:52,479 calculated you would meet more than 548 00:20:57,239 --> 00:20:54,639 10,000 times the amount of co2 that's in 549 00:20:59,669 --> 00:20:57,249 our atmosphere today the co2 is not just 550 00:21:02,369 --> 00:20:59,679 a greenhouse gas it's also a chemically 551 00:21:04,409 --> 00:21:02,379 active gas and we know that from our 552 00:21:05,999 --> 00:21:04,419 answer per Jenica missions of the you 553 00:21:08,339 --> 00:21:06,009 know ocean has become acidified if 554 00:21:11,219 --> 00:21:08,349 you're in a room with too much co2 it 555 00:21:13,019 --> 00:21:11,229 can be deleterious to you can you could 556 00:21:16,049 --> 00:21:13,029 you you could get co2 poisoning it's 557 00:21:18,329 --> 00:21:16,059 called hypercapnia a blood acidosis and 558 00:21:20,639 --> 00:21:18,339 it turns out that if you were to place 559 00:21:23,070 --> 00:21:20,649 the earth in most of the habitable zone 560 00:21:25,200 --> 00:21:23,080 and let it equilibrate to the amount 561 00:21:27,930 --> 00:21:25,210 that you would need to maintain above 562 00:21:30,719 --> 00:21:27,940 freezing conditions for most of that 563 00:21:33,690 --> 00:21:30,729 zone humans and most animals on earth 564 00:21:37,139 --> 00:21:33,700 would not be able to survive and so this 565 00:21:39,029 --> 00:21:37,149 is a little bit of a wrinkle in in in 566 00:21:40,799 --> 00:21:39,039 another dimension to the hackls and i 567 00:21:42,869 --> 00:21:40,809 say i would say it doesn't necessarily 568 00:21:44,969 --> 00:21:42,879 exclude it doesn't exclude at all the 569 00:21:47,279 --> 00:21:44,979 existence of bio signatures or microbial 570 00:21:49,409 --> 00:21:47,289 life but it does make us question about 571 00:21:51,329 --> 00:21:49,419 whether the entire how durable zone is 572 00:21:52,799 --> 00:21:51,339 suitable for the kinds of bye it's gonna 573 00:21:53,969 --> 00:21:52,809 kind of biosphere we find on earth today 574 00:21:55,589 --> 00:21:53,979 mm-hmm 575 00:21:57,180 --> 00:21:55,599 that's a good point because meaning 576 00:21:58,589 --> 00:21:57,190 there could be could be organisms who 577 00:22:00,810 --> 00:21:58,599 survive and there's other environments 578 00:22:02,489 --> 00:22:00,820 quite well but just not the kind of the 579 00:22:04,919 --> 00:22:02,499 planet biosphere that we have here right 580 00:22:06,450 --> 00:22:04,929 now right well and absolutely and 581 00:22:08,549 --> 00:22:06,460 there's a time dimension too which is 582 00:22:10,379 --> 00:22:08,559 really fascinating because when you look 583 00:22:11,579 --> 00:22:10,389 at the habitable zone in most 584 00:22:13,859 --> 00:22:11,589 definitions of the habitable zone 585 00:22:15,180 --> 00:22:13,869 particularly the conservative one the 586 00:22:16,529 --> 00:22:15,190 earth is at the very inner edge of the 587 00:22:18,930 --> 00:22:16,539 habitable zone and you think that's kind 588 00:22:20,459 --> 00:22:18,940 of odd but if you think about you know 589 00:22:22,289 --> 00:22:20,469 the distribution of co2 and habits on 590 00:22:24,180 --> 00:22:22,299 you expect it to be low the inner edge 591 00:22:26,700 --> 00:22:24,190 and and high at the outer edge 592 00:22:28,619 --> 00:22:26,710 now these habitable zones are not static 593 00:22:30,450 --> 00:22:28,629 in geologic time they changed as the 594 00:22:32,099 --> 00:22:30,460 Stars bright and Brett Stars brightened 595 00:22:34,649 --> 00:22:32,109 with time just as our Sun has so you 596 00:22:36,180 --> 00:22:34,659 earth started more more or less in the 597 00:22:37,450 --> 00:22:36,190 middle of the habitable zone and it's 598 00:22:38,980 --> 00:22:37,460 moved inward with time 599 00:22:41,139 --> 00:22:38,990 and what do you know we find ourselves 600 00:22:44,200 --> 00:22:41,149 at the inner edge of the habitable zone 601 00:22:46,240 --> 00:22:44,210 today when the co2 problem wouldn't 602 00:22:48,269 --> 00:22:46,250 exist and so it's not necessarily 603 00:22:51,090 --> 00:22:48,279 definitive but it is suggestive that 604 00:22:54,310 --> 00:22:51,100 perhaps that isn't a coincidence Oh 605 00:22:56,139 --> 00:22:54,320 awesome yeah this is really cool 606 00:22:57,970 --> 00:22:56,149 research I do want to open it up soon to 607 00:23:00,610 --> 00:22:57,980 audience questions and so I think just 608 00:23:02,860 --> 00:23:00,620 before we get there if you could so so 609 00:23:05,889 --> 00:23:02,870 one I'd love if you could just tell us 610 00:23:07,029 --> 00:23:05,899 you know what what tools do you need for 611 00:23:09,779 --> 00:23:07,039 your work specifically to do 612 00:23:13,330 --> 00:23:09,789 computational modeling not to mention 613 00:23:14,740 --> 00:23:13,340 what tools in the near future from 614 00:23:16,330 --> 00:23:14,750 computational methods as well as the 615 00:23:19,029 --> 00:23:16,340 upcoming telescopes are you most excited 616 00:23:23,260 --> 00:23:19,039 about to really advance this work 617 00:23:25,060 --> 00:23:23,270 forward well well the tools III do a lot 618 00:23:26,830 --> 00:23:25,070 of models so I'm using photochemical 619 00:23:28,899 --> 00:23:26,840 models climate models and radio transfer 620 00:23:31,480 --> 00:23:28,909 models and that allows me to to 621 00:23:34,269 --> 00:23:31,490 stimulate planetary States you know 622 00:23:35,950 --> 00:23:34,279 climate States chemical States for 623 00:23:38,560 --> 00:23:35,960 planets if you say change the star 624 00:23:40,120 --> 00:23:38,570 change location in the hobble zone and 625 00:23:41,440 --> 00:23:40,130 things like that and then simulate the 626 00:23:42,700 --> 00:23:41,450 spectral appearance of that planet as 627 00:23:44,230 --> 00:23:42,710 they would be observed by future 628 00:23:46,570 --> 00:23:44,240 observatories what really excites me as 629 00:23:49,029 --> 00:23:46,580 a prospect of these future observatories 630 00:23:51,519 --> 00:23:49,039 so there are three competing 631 00:23:53,169 --> 00:23:51,529 observatories that can potentially 632 00:23:55,990 --> 00:23:53,179 characterize terrestrial planet 633 00:23:58,419 --> 00:23:56,000 atmospheres in the astrophysics 2020 to 634 00:24:01,389 --> 00:23:58,429 Keadle two of them would be able to 635 00:24:02,620 --> 00:24:01,399 image terrestrial temperate planets and 636 00:24:05,880 --> 00:24:02,630 hobbles none of their stars they're 637 00:24:08,550 --> 00:24:05,890 called hab have x2 have 638 00:24:11,460 --> 00:24:08,560 you know the large optical infrared 639 00:24:13,560 --> 00:24:11,470 surveyor and and then there's also the 640 00:24:14,730 --> 00:24:13,570 Origin Space Telescope which is similar 641 00:24:16,980 --> 00:24:14,740 to JD boost II but would be more 642 00:24:20,310 --> 00:24:16,990 sensitive and would be able to probe the 643 00:24:24,810 --> 00:24:20,320 atmospheres of transiting planets around 644 00:24:27,240 --> 00:24:24,820 em door stars and so these these would 645 00:24:30,090 --> 00:24:27,250 really be the workhorses in the future 646 00:24:31,770 --> 00:24:30,100 for determining the distribution of life 647 00:24:33,900 --> 00:24:31,780 in the universe this would be our chance 648 00:24:37,050 --> 00:24:33,910 to do a survey of multiple habitable 649 00:24:39,060 --> 00:24:37,060 zone planets and probe their atmospheres 650 00:24:41,880 --> 00:24:39,070 for gaseous bio signatures and perhaps 651 00:24:43,890 --> 00:24:41,890 their surfaces as well and really start 652 00:24:46,740 --> 00:24:43,900 to get some robust statistics about how 653 00:24:48,660 --> 00:24:46,750 common not just habitable planets are 654 00:24:50,760 --> 00:24:48,670 but maybe even an inhabited planets and 655 00:24:52,940 --> 00:24:50,770 they could tell us that life is common 656 00:24:54,840 --> 00:24:52,950 they could tell us that life is rare 657 00:24:55,860 --> 00:24:54,850 that's awesome you know I'm looking 658 00:24:58,290 --> 00:24:55,870 forward to a lot of these upcoming 659 00:24:59,670 --> 00:24:58,300 telescopes if there were you know some 660 00:25:01,980 --> 00:24:59,680 young students right now in high school 661 00:25:04,140 --> 00:25:01,990 or undergraduate level who might want to 662 00:25:05,630 --> 00:25:04,150 work on those missions in the future if 663 00:25:07,350 --> 00:25:05,640 they get funded if they go into space 664 00:25:09,690 --> 00:25:07,360 what would you recommend to those 665 00:25:12,540 --> 00:25:09,700 students so get started right now to get 666 00:25:15,060 --> 00:25:12,550 involved in that well I mean taking 667 00:25:17,010 --> 00:25:15,070 taking physics and math is important if 668 00:25:19,410 --> 00:25:17,020 you want to be a scientist or an 669 00:25:22,260 --> 00:25:19,420 engineer you can be an engineer and work 670 00:25:24,330 --> 00:25:22,270 on the this on the spacecraft themselves 671 00:25:25,530 --> 00:25:24,340 or you or you could be a scientist and 672 00:25:28,400 --> 00:25:25,540 think about how to interpret the 673 00:25:30,480 --> 00:25:28,410 observations plan the observations and 674 00:25:33,360 --> 00:25:30,490 in either way you're going to need a 675 00:25:36,450 --> 00:25:33,370 strong quantitative background so math 676 00:25:37,770 --> 00:25:36,460 and physics and but also expand your 677 00:25:39,960 --> 00:25:37,780 horizons and think about the meaning 678 00:25:42,330 --> 00:25:39,970 behind this so don't close yourself only 679 00:25:45,390 --> 00:25:42,340 in the stem classes take some art and 680 00:25:46,950 --> 00:25:45,400 and and philosophy and and and and 681 00:25:49,380 --> 00:25:46,960 writing classes communication is 682 00:25:50,670 --> 00:25:49,390 incredibly important for scientists it's 683 00:25:52,320 --> 00:25:50,680 one of the most important things we do 684 00:25:54,960 --> 00:25:52,330 we spend most of our time communicating 685 00:25:56,970 --> 00:25:54,970 just need scientists we need people who 686 00:25:59,820 --> 00:25:56,980 can help us tell the story of what the 687 00:26:01,800 --> 00:25:59,830 science is is saying we need people who 688 00:26:03,330 --> 00:26:01,810 are science communicators and so there's 689 00:26:05,790 --> 00:26:03,340 a whole ecosystem that's built around 690 00:26:08,790 --> 00:26:05,800 these things we interested in finding 691 00:26:11,790 --> 00:26:08,800 life beyond its a compelling question it 692 00:26:13,620 --> 00:26:11,800 motivates all of us and you don't need 693 00:26:16,950 --> 00:26:13,630 to necessarily be a scientist to be part 694 00:26:19,350 --> 00:26:16,960 of that yeah and as a communicator of 695 00:26:20,880 --> 00:26:19,360 science myself I love hear you say that 696 00:26:22,410 --> 00:26:20,890 um so just before I open it up now 697 00:26:24,480 --> 00:26:22,420 finally to the audience questions one 698 00:26:27,000 --> 00:26:24,490 more thing I want to ask I do just want 699 00:26:28,830 --> 00:26:27,010 to know in prepping for this episode we 700 00:26:31,650 --> 00:26:28,840 discovered that you actually enjoy a lot 701 00:26:33,180 --> 00:26:31,660 of gaming and so I'd like to know how 702 00:26:39,300 --> 00:26:33,190 you as an astrobiologist studying 703 00:26:41,340 --> 00:26:39,310 exoplanets how you relax yes so um so as 704 00:26:44,160 --> 00:26:41,350 many of us many of us interested in 705 00:26:46,080 --> 00:26:44,170 science started off in being interested 706 00:26:48,270 --> 00:26:46,090 in games I was interested in in 707 00:26:51,720 --> 00:26:48,280 civilization I played many hours as a 708 00:26:53,280 --> 00:26:51,730 teenager of civilization now I don't 709 00:26:55,320 --> 00:26:53,290 have a lot of time for gaming but when I 710 00:26:57,660 --> 00:26:55,330 do I play a game called stellaris which 711 00:27:00,540 --> 00:26:57,670 is about exploring a galaxy and making 712 00:27:03,750 --> 00:27:00,550 scientific discoveries and expanding 713 00:27:05,700 --> 00:27:03,760 it's a 4x game and what I like about is 714 00:27:09,210 --> 00:27:05,710 you can pause it and start it you know 715 00:27:12,090 --> 00:27:09,220 according to your own schedule so that's 716 00:27:14,460 --> 00:27:12,100 one of the games that I play to relax 717 00:27:20,640 --> 00:27:14,470 that like reading as a teenager a lot of 718 00:27:25,050 --> 00:27:20,650 the Asimov magazine analog I enjoy the 719 00:27:28,100 --> 00:27:25,060 novels by arthur c clarke and azimoff 720 00:27:30,900 --> 00:27:28,110 and david brin some of the authors 721 00:27:32,520 --> 00:27:30,910 that's awesome you know so you know all 722 00:27:34,200 --> 00:27:32,530 of us in the sciences and engineering 723 00:27:35,550 --> 00:27:34,210 and other rooms like this we also all 724 00:27:38,850 --> 00:27:35,560 have these other pursuits that kind of 725 00:27:39,750 --> 00:27:38,860 you know fill in our lives so I am going 726 00:27:41,730 --> 00:27:39,760 to open it now for the audience 727 00:27:43,800 --> 00:27:41,740 questions and thank you to our audience 728 00:27:46,590 --> 00:27:43,810 for bearing with us here technical 729 00:27:47,970 --> 00:27:46,600 glitches we've had along the way just 730 00:27:50,790 --> 00:27:47,980 remember you can ask your questions on 731 00:27:52,830 --> 00:27:50,800 twitter using hashtag ask aster bio into 732 00:27:55,140 --> 00:27:52,840 the second net chat or on the Facebook 733 00:27:57,720 --> 00:27:55,150 page for NASA Astrobiology if you're 734 00:28:00,410 --> 00:27:57,730 watching there as well so Eddie the very 735 00:28:03,030 --> 00:28:00,420 first question comes from dr. Jim pass 736 00:28:06,180 --> 00:28:03,040 of the Astro sociology Research 737 00:28:08,250 --> 00:28:06,190 Institute and dr. pass once this wants 738 00:28:11,250 --> 00:28:08,260 to know since he's a social scientist 739 00:28:12,990 --> 00:28:11,260 himself what your thoughts are about the 740 00:28:15,350 --> 00:28:13,000 types of techno signatures you would 741 00:28:18,420 --> 00:28:15,360 favor in the search for extraterrestrial 742 00:28:20,670 --> 00:28:18,430 societies and if you could maybe mention 743 00:28:23,040 --> 00:28:20,680 the relationship and differences between 744 00:28:25,320 --> 00:28:23,050 bio signatures and techno signatures as 745 00:28:28,320 --> 00:28:25,330 well and I use the word bio signature to 746 00:28:30,549 --> 00:28:28,330 mean on technological life so so 747 00:28:35,710 --> 00:28:30,559 evidence of 748 00:28:39,730 --> 00:28:35,720 analogues to bacteria or algae or or you 749 00:28:42,279 --> 00:28:39,740 know plants and and and they can affect 750 00:28:46,480 --> 00:28:42,289 their planet in in in drastic ways as we 751 00:28:47,919 --> 00:28:46,490 see on our on earth but a technical 752 00:28:49,990 --> 00:28:47,929 signature would be specifically an 753 00:28:51,940 --> 00:28:50,000 indication of a technologically advanced 754 00:28:54,039 --> 00:28:51,950 civilization and so you could think of a 755 00:28:56,409 --> 00:28:54,049 techno signature as present in a broad 756 00:29:00,130 --> 00:28:56,419 sense a radio wave that's generated by a 757 00:29:02,350 --> 00:29:00,140 transmitter by an laser flash by a 758 00:29:07,090 --> 00:29:02,360 structure perhaps that could only be 759 00:29:08,919 --> 00:29:07,100 made artificially by even a certain kind 760 00:29:10,269 --> 00:29:08,929 of molecule in an exoplanet atmosphere 761 00:29:12,760 --> 00:29:10,279 that can only be created through 762 00:29:14,169 --> 00:29:12,770 industrial processes so that would be 763 00:29:16,419 --> 00:29:14,179 those would be examples of techno 764 00:29:18,549 --> 00:29:16,429 signatures and so which ones do I favor 765 00:29:20,680 --> 00:29:18,559 well I think the advantage to bio 766 00:29:22,810 --> 00:29:20,690 signatures is that in the future we can 767 00:29:24,610 --> 00:29:22,820 we can do a volume limited survey we can 768 00:29:26,169 --> 00:29:24,620 look probe the atmospheres of planets 769 00:29:30,700 --> 00:29:26,179 that are in the solar neighborhood and 770 00:29:33,010 --> 00:29:30,710 we can look for for for for oxygen for 771 00:29:34,360 --> 00:29:33,020 methane for nitrous oxide and we can say 772 00:29:37,659 --> 00:29:34,370 yes or no those are present in 773 00:29:42,159 --> 00:29:37,669 detectable quantities for techno 774 00:29:44,019 --> 00:29:42,169 signatures I think we we have we have an 775 00:29:45,490 --> 00:29:44,029 advantage in the sense that potentially 776 00:29:47,560 --> 00:29:45,500 if you have a strong enough transmitter 777 00:29:49,539 --> 00:29:47,570 you could you could find a sign of 778 00:29:52,029 --> 00:29:49,549 intelligence from a much larger distance 779 00:29:53,740 --> 00:29:52,039 away so instead of tens of light-years 780 00:29:56,560 --> 00:29:53,750 maybe hundreds or thousands of 781 00:29:58,090 --> 00:29:56,570 light-years away if it exists and the 782 00:30:00,730 --> 00:29:58,100 problem of course is that you can't do a 783 00:30:02,529 --> 00:30:00,740 volume limited survey and so you can't 784 00:30:04,510 --> 00:30:02,539 necessarily you've set a lower limit on 785 00:30:07,750 --> 00:30:04,520 the prevalence of these techno 786 00:30:10,659 --> 00:30:07,760 signatures that are out there but I do 787 00:30:13,269 --> 00:30:10,669 favor the idea of of looking for them 788 00:30:16,299 --> 00:30:13,279 because we don't know until we look and 789 00:30:18,100 --> 00:30:16,309 and and there's a there's assumptions 790 00:30:20,080 --> 00:30:18,110 people have assumptions about whether 791 00:30:22,720 --> 00:30:20,090 life is rare or common and assumptions 792 00:30:25,090 --> 00:30:22,730 about whether civilizations are common 793 00:30:27,940 --> 00:30:25,100 or rare and the only way that we can be 794 00:30:29,740 --> 00:30:27,950 sure is to actually make the 795 00:30:33,010 --> 00:30:29,750 observations and to make the effort to 796 00:30:34,389 --> 00:30:33,020 find them and say that that bio 797 00:30:36,789 --> 00:30:34,399 signatures and techno signatures are 798 00:30:38,500 --> 00:30:36,799 complementary in this way that we can do 799 00:30:39,620 --> 00:30:38,510 this volume limited survey in the future 800 00:30:41,450 --> 00:30:39,630 for biosignature 801 00:30:44,990 --> 00:30:41,460 and we can kind of look at much larger 802 00:30:47,180 --> 00:30:45,000 distances for for techno signatures that 803 00:30:51,500 --> 00:30:47,190 may be more more detectable and more 804 00:30:53,720 --> 00:30:51,510 obvious mm-hmm yeah so our next question 805 00:30:56,180 --> 00:30:53,730 comes from autoroute mohanty at stray 806 00:30:56,900 --> 00:30:56,190 ologist on twitter autoroute wants to 807 00:30:58,640 --> 00:30:56,910 know 808 00:31:00,260 --> 00:30:58,650 so in this realm of talking about 809 00:31:02,030 --> 00:31:00,270 exoplanet atmospheres and we're talking 810 00:31:04,880 --> 00:31:02,040 a lot about you know that the Goldilocks 811 00:31:06,230 --> 00:31:04,890 zone the habitable zone and an honor 812 00:31:08,390 --> 00:31:06,240 wants to know if you think that we're 813 00:31:11,750 --> 00:31:08,400 missing out a lot of potentially 814 00:31:13,070 --> 00:31:11,760 habitable extrasolar bodies because of 815 00:31:14,450 --> 00:31:13,080 things like you know and in our solar 816 00:31:15,890 --> 00:31:14,460 system we have these icy worlds in the 817 00:31:19,610 --> 00:31:15,900 outer solar system that might have life 818 00:31:21,020 --> 00:31:19,620 and oceans are we missing out on on ways 819 00:31:23,480 --> 00:31:21,030 of looking for those kinds of life as 820 00:31:25,070 --> 00:31:23,490 well well I think this speaks to the 821 00:31:26,930 --> 00:31:25,080 complementarity of the search for life 822 00:31:28,820 --> 00:31:26,940 within the solar system and the search 823 00:31:31,039 --> 00:31:28,830 for life outside our solar system and so 824 00:31:33,620 --> 00:31:31,049 the reason why we're looking for planets 825 00:31:36,289 --> 00:31:33,630 in the habitable zone you know so-called 826 00:31:37,850 --> 00:31:36,299 habitable zone and exoplanets is the 827 00:31:40,820 --> 00:31:37,860 idea that you have this interface 828 00:31:43,130 --> 00:31:40,830 between the ocean or the land and the 829 00:31:45,350 --> 00:31:43,140 atmosphere so you have a way for bio 830 00:31:47,690 --> 00:31:45,360 signature gases for example to mix into 831 00:31:50,030 --> 00:31:47,700 the atmosphere and then create a signal 832 00:31:51,500 --> 00:31:50,040 that can be detected remotely and then 833 00:31:53,330 --> 00:31:51,510 that's robust enough to be detected over 834 00:31:54,980 --> 00:31:53,340 interstellar distances if the life is 835 00:31:57,049 --> 00:31:54,990 under an ice shell that's much more 836 00:31:59,150 --> 00:31:57,059 difficult if not impossible to detect 837 00:32:00,440 --> 00:31:59,160 remotely however we do have these 838 00:32:02,360 --> 00:32:00,450 examples of potentially habitable 839 00:32:06,680 --> 00:32:02,370 environments within our solar system and 840 00:32:10,400 --> 00:32:06,690 we could send in sissu probes to to 841 00:32:12,200 --> 00:32:10,410 sample those environments and so that 842 00:32:13,730 --> 00:32:12,210 could tell us if if we find life on 843 00:32:17,299 --> 00:32:13,740 Europa and Enceladus that icy moons are 844 00:32:20,090 --> 00:32:17,309 very common habitats and and in the in 845 00:32:22,850 --> 00:32:20,100 the universe in general but right now 846 00:32:24,950 --> 00:32:22,860 there's no way to look for them if 847 00:32:26,030 --> 00:32:24,960 they're in outside our solar system so 848 00:32:27,799 --> 00:32:26,040 it's really a matter of practicality 849 00:32:29,060 --> 00:32:27,809 we're not saying what the concept that 850 00:32:30,320 --> 00:32:29,070 the habitable zone that there are no 851 00:32:31,970 --> 00:32:30,330 habitable environments outside the 852 00:32:34,070 --> 00:32:31,980 Hamill's and we're saying is those are 853 00:32:36,560 --> 00:32:34,080 the places we have the best chance of 854 00:32:39,140 --> 00:32:36,570 detecting planetary biosphere remotely 855 00:32:40,280 --> 00:32:39,150 mm-hm that's awesome yeah so so on earth 856 00:32:43,669 --> 00:32:40,290 actually kind as a follow-up question 857 00:32:44,960 --> 00:32:43,679 then to kind of going on that so you 858 00:32:46,970 --> 00:32:44,970 know you're working a lot in 859 00:32:48,590 --> 00:32:46,980 computational modeling of the BIOS 860 00:32:50,240 --> 00:32:48,600 features that we're going to be looking 861 00:32:51,590 --> 00:32:50,250 for very soon at the next generation of 862 00:32:54,110 --> 00:32:51,600 telescopes 863 00:32:56,510 --> 00:32:54,120 and may potentially find honor Roop 864 00:32:58,510 --> 00:32:56,520 wants to know can we expect to see 865 00:33:01,220 --> 00:32:58,520 techniques being developed to analyze 866 00:33:03,140 --> 00:33:01,230 exoplanets sub surfaces in the near 867 00:33:05,810 --> 00:33:03,150 future 868 00:33:07,940 --> 00:33:05,820 III would say that that what we need is 869 00:33:10,100 --> 00:33:07,950 a way to translate what's happening in 870 00:33:12,440 --> 00:33:10,110 the subsurface to the atmosphere and so 871 00:33:13,910 --> 00:33:12,450 if there's an exchange of gases from the 872 00:33:15,410 --> 00:33:13,920 subsurface the atmosphere that creates a 873 00:33:17,510 --> 00:33:15,420 disequilibrium that's something that 874 00:33:20,299 --> 00:33:17,520 could potentially be looked for but what 875 00:33:22,130 --> 00:33:20,309 we need is the the the the composition 876 00:33:23,750 --> 00:33:22,140 of the atmosphere to have change in a 877 00:33:27,110 --> 00:33:23,760 way that's figured that that can 878 00:33:28,700 --> 00:33:27,120 fingerprint life for and for those gases 879 00:33:33,049 --> 00:33:28,710 to be abundant enough to be detected 880 00:33:34,760 --> 00:33:33,059 over interstellar distances mmm okay so 881 00:33:37,100 --> 00:33:34,770 we have another question here so a lot 882 00:33:39,620 --> 00:33:37,110 of folks might have noticed yesterday 883 00:33:41,090 --> 00:33:39,630 they might have heard some news that a 884 00:33:44,210 --> 00:33:41,100 new paper came out suggesting that 885 00:33:46,820 --> 00:33:44,220 there's some 30-ish planets in our Milky 886 00:33:49,640 --> 00:33:46,830 Way that likely have life we have a 887 00:33:52,490 --> 00:33:49,650 question from the rebel educator Doctor 888 00:33:53,230 --> 00:33:52,500 of Education on Twitter at dr. andrew 889 00:33:56,270 --> 00:33:53,240 kemp 890 00:33:58,580 --> 00:33:56,280 dr. Kempe wants to know with the news 891 00:34:00,830 --> 00:33:58,590 that there are potential 36 planets with 892 00:34:02,690 --> 00:34:00,840 life similar to ours would it make sense 893 00:34:04,850 --> 00:34:02,700 that some of these would be vastly more 894 00:34:07,180 --> 00:34:04,860 developed than we are if so is it 895 00:34:11,990 --> 00:34:07,190 logical that they know about us 896 00:34:14,180 --> 00:34:12,000 well so this this is a paper that I 897 00:34:16,460 --> 00:34:14,190 admittedly have not had a chance to read 898 00:34:18,889 --> 00:34:16,470 yet so I'll speak more generally about 899 00:34:20,720 --> 00:34:18,899 about the Drake Equation and about the 900 00:34:23,919 --> 00:34:20,730 search for extraterrestrial intelligence 901 00:34:26,180 --> 00:34:23,929 and so the Drake Equation is a way of 902 00:34:28,879 --> 00:34:26,190 kind of parameterizing our ignorance 903 00:34:31,070 --> 00:34:28,889 about how many civilizations are in our 904 00:34:32,780 --> 00:34:31,080 in the are in the galaxy and so you take 905 00:34:35,899 --> 00:34:32,790 the number of stars times the fraction 906 00:34:37,700 --> 00:34:35,909 of those that have planets times the 907 00:34:40,490 --> 00:34:37,710 fraction of those planets that could 908 00:34:42,320 --> 00:34:40,500 develop that are habitable times the 909 00:34:44,450 --> 00:34:42,330 fraction of those habitable environments 910 00:34:48,500 --> 00:34:44,460 that actually develop life and then so 911 00:34:51,230 --> 00:34:48,510 on and so forth the end is how long the 912 00:34:53,389 --> 00:34:51,240 civilization lasts on that planet and so 913 00:34:55,220 --> 00:34:53,399 that's a really key thing to consider is 914 00:34:57,139 --> 00:34:55,230 that I believe that many of these 915 00:35:00,670 --> 00:34:57,149 assumptions we assume that that last 916 00:35:03,590 --> 00:35:00,680 numbers is comparable to the to the 917 00:35:05,750 --> 00:35:03,600 current longevity of our technic 918 00:35:06,980 --> 00:35:05,760 civilization and so that's kind of a 919 00:35:09,830 --> 00:35:06,990 built-in assumption that they're similar 920 00:35:11,990 --> 00:35:09,840 to us but I do want to jump off of that 921 00:35:14,030 --> 00:35:12,000 because if you think about how old the 922 00:35:16,640 --> 00:35:14,040 universe is and and how old our galaxy 923 00:35:18,740 --> 00:35:16,650 is you can leverage something called the 924 00:35:21,770 --> 00:35:18,750 cosmic calendar which is collapsing the 925 00:35:25,280 --> 00:35:21,780 whole history of the universe down to 926 00:35:27,500 --> 00:35:25,290 one year and to illustrate that the Sun 927 00:35:30,170 --> 00:35:27,510 only formed four months ago in this 928 00:35:32,600 --> 00:35:30,180 timeline dinosaurs roam the earth on 929 00:35:34,460 --> 00:35:32,610 December 25th humanity developed 930 00:35:36,860 --> 00:35:34,470 developed eight minutes ago and the 931 00:35:40,040 --> 00:35:36,870 average human lifespan is 0.2 seconds in 932 00:35:42,920 --> 00:35:40,050 this cosmic year and so if you imagine a 933 00:35:47,660 --> 00:35:42,930 civilization that arose just a minute 934 00:35:51,230 --> 00:35:47,670 before ours ten minutes a day it would 935 00:35:53,270 --> 00:35:51,240 be incomprehensible beyond us when you 936 00:35:54,440 --> 00:35:53,280 consider the fact that the ten thousand 937 00:35:56,690 --> 00:35:54,450 years between the invention of 938 00:35:59,990 --> 00:35:56,700 agriculture and our current time is just 939 00:36:02,090 --> 00:36:00,000 this you know less than a less than a 940 00:36:04,130 --> 00:36:02,100 minute it's about it's about 25 seconds 941 00:36:05,900 --> 00:36:04,140 in this cosmic timeline so I would 942 00:36:07,310 --> 00:36:05,910 imagine that if we did find an 943 00:36:08,390 --> 00:36:07,320 extraterrestrial civilization the 944 00:36:10,730 --> 00:36:08,400 chances of us finding one that's 945 00:36:12,560 --> 00:36:10,740 comparable to us is is zero 946 00:36:14,600 --> 00:36:12,570 they're probably far ahead Oh 947 00:36:16,070 --> 00:36:14,610 interesting and and it's always 948 00:36:17,360 --> 00:36:16,080 compelling to think about you know time 949 00:36:19,910 --> 00:36:17,370 in that way that you know we really have 950 00:36:22,940 --> 00:36:19,920 been around for a very short time a blip 951 00:36:25,160 --> 00:36:22,950 in cosmic time and I also recommend for 952 00:36:26,720 --> 00:36:25,170 for our audience watching the website 953 00:36:30,080 --> 00:36:26,730 information is beautiful has a really 954 00:36:31,310 --> 00:36:30,090 cool Drake Equation interactive graphic 955 00:36:33,050 --> 00:36:31,320 that you can play with and change those 956 00:36:34,250 --> 00:36:33,060 numbers and kind of give yourself an 957 00:36:35,840 --> 00:36:34,260 idea of what happens when you start 958 00:36:39,410 --> 00:36:35,850 actually moving those numbers around so 959 00:36:41,450 --> 00:36:39,420 I highly recommend our next question for 960 00:36:45,500 --> 00:36:41,460 you Eddie comes from guara yaw table on 961 00:36:48,080 --> 00:36:45,510 Facebook Gaurav asks which instruments 962 00:36:50,840 --> 00:36:48,090 are used to detect and study these bio 963 00:36:52,580 --> 00:36:50,850 signatures and then kind of following on 964 00:36:54,980 --> 00:36:52,590 and this might be more specific to our 965 00:36:57,170 --> 00:36:54,990 solar system for now is there any way to 966 00:36:58,910 --> 00:36:57,180 miniaturize like mass spectroscopy that 967 00:37:01,490 --> 00:36:58,920 we could put on a spaceship and then and 968 00:37:04,250 --> 00:37:01,500 then detect bio signatures yeah okay so 969 00:37:06,080 --> 00:37:04,260 I'll do the first one so there there are 970 00:37:09,860 --> 00:37:06,090 many different technologies that have 971 00:37:11,810 --> 00:37:09,870 been proposed to detect the atmosphere 972 00:37:13,110 --> 00:37:11,820 and potentially probe the services of 973 00:37:16,650 --> 00:37:13,120 earth-sized exoplanet 974 00:37:20,160 --> 00:37:16,660 and so the challenge here is is multi 975 00:37:21,960 --> 00:37:20,170 flow multi fold so the earth is out out 976 00:37:23,940 --> 00:37:21,970 shown by the Sun by a factor of ten 977 00:37:26,910 --> 00:37:23,950 billion so that's ten to the ten 978 00:37:28,950 --> 00:37:26,920 and so you would you need the technology 979 00:37:31,110 --> 00:37:28,960 if you want to directly image the planet 980 00:37:33,000 --> 00:37:31,120 to null out the star light from That 981 00:37:34,950 --> 00:37:33,010 star revealed a star light of the planet 982 00:37:37,200 --> 00:37:34,960 or the the reflectance that reflected 983 00:37:38,550 --> 00:37:37,210 light from the planet and there are a 984 00:37:40,620 --> 00:37:38,560 couple of ways to do that one is called 985 00:37:42,630 --> 00:37:40,630 a coronagraph and the other is called a 986 00:37:45,810 --> 00:37:42,640 star shade the coronagraph is internal 987 00:37:48,630 --> 00:37:45,820 to the telescope and we have examples of 988 00:37:51,060 --> 00:37:48,640 these already the the challenge is 989 00:37:53,790 --> 00:37:51,070 getting to this level of one part in ten 990 00:37:55,980 --> 00:37:53,800 billion and so currently nasa stats 991 00:37:57,540 --> 00:37:55,990 studying both coronagraphs and starshade 992 00:37:59,610 --> 00:37:57,550 star shade is an external of culture 993 00:38:01,890 --> 00:37:59,620 that would be a separate spacecraft that 994 00:38:03,330 --> 00:38:01,900 would have petals that are shaped in 995 00:38:04,950 --> 00:38:03,340 just the right way to null out the light 996 00:38:07,470 --> 00:38:04,960 from the star and reveal the light of 997 00:38:09,210 --> 00:38:07,480 the planet and and there are current 998 00:38:10,710 --> 00:38:09,220 tests going on that are getting very 999 00:38:13,680 --> 00:38:10,720 close to this ten to the negative 10 1000 00:38:15,360 --> 00:38:13,690 star lights depression level and so they 1001 00:38:16,710 --> 00:38:15,370 open through a field a planet and then 1002 00:38:19,230 --> 00:38:16,720 it's just a matter of using a 1003 00:38:22,290 --> 00:38:19,240 spectrograph to to break up the light 1004 00:38:24,810 --> 00:38:22,300 from the planet and reveal the molecular 1005 00:38:26,760 --> 00:38:24,820 composition of the atmosphere that's one 1006 00:38:28,350 --> 00:38:26,770 way of doing it there's also the way of 1007 00:38:29,760 --> 00:38:28,360 doing it where you where you look at the 1008 00:38:31,860 --> 00:38:29,770 light filtered through the planet as 1009 00:38:33,240 --> 00:38:31,870 it's transiting and again what you have 1010 00:38:36,090 --> 00:38:33,250 to do is you have to subtract off the 1011 00:38:38,670 --> 00:38:36,100 light from the star and and reveal the 1012 00:38:40,530 --> 00:38:38,680 light from the planet and and the light 1013 00:38:42,120 --> 00:38:40,540 from and that light reveals the 1014 00:38:44,160 --> 00:38:42,130 molecular composition of the atmosphere 1015 00:38:48,210 --> 00:38:44,170 and so we have done that already for 1016 00:38:50,490 --> 00:38:48,220 large large planets gaseous planets it 1017 00:38:53,190 --> 00:38:50,500 whenever I think about I mean just the 1018 00:38:56,220 --> 00:38:53,200 very thought that we are capturing that 1019 00:38:59,760 --> 00:38:56,230 little itty bitty amount of star light 1020 00:39:01,770 --> 00:38:59,770 coming just through that small veneer of 1021 00:39:04,380 --> 00:39:01,780 atmosphere around a planet and then 1022 00:39:06,000 --> 00:39:04,390 we're able to actually subtract that 1023 00:39:08,070 --> 00:39:06,010 from the star light and actually do some 1024 00:39:10,080 --> 00:39:08,080 some chemical some chemistry with it and 1025 00:39:14,490 --> 00:39:10,090 actually understand it is just it's 1026 00:39:16,140 --> 00:39:14,500 almost so much shocking it's it's a it's 1027 00:39:18,690 --> 00:39:16,150 it's it's quite a fine measurement you 1028 00:39:21,270 --> 00:39:18,700 know so so the earth transiting the Sun 1029 00:39:23,010 --> 00:39:21,280 is one part in 10,000 and that's the 1030 00:39:24,690 --> 00:39:23,020 whole planet and then we talk about the 1031 00:39:26,250 --> 00:39:24,700 atmosphere you're talking about parts 1032 00:39:29,320 --> 00:39:26,260 parts per million 1033 00:39:30,940 --> 00:39:29,330 wowthat's it's so small and I hope 1034 00:39:32,860 --> 00:39:30,950 people spend some time just thinking 1035 00:39:35,020 --> 00:39:32,870 about we know how far we've come in 1036 00:39:37,420 --> 00:39:35,030 trying to understand this and how far we 1037 00:39:39,940 --> 00:39:37,430 can go yet in the future and doing more 1038 00:39:41,770 --> 00:39:39,950 there I actually want to jump out just 1039 00:39:46,020 --> 00:39:41,780 for a second and ask if you've heard of 1040 00:39:50,200 --> 00:39:46,030 this recent idea of sending a series of 1041 00:39:52,480 --> 00:39:50,210 telescopes far from our Sun and then 1042 00:39:55,570 --> 00:39:52,490 kind of looking back and using the Sun 1043 00:39:57,430 --> 00:39:55,580 as its own gravitational lens to 1044 00:40:00,040 --> 00:39:57,440 actually look at exoplanets from far 1045 00:40:01,150 --> 00:40:00,050 away so maybe you know and this wouldn't 1046 00:40:03,340 --> 00:40:01,160 have any time soon it would take a very 1047 00:40:05,770 --> 00:40:03,350 long time to build this but we could 1048 00:40:08,170 --> 00:40:05,780 build an array of gravitational lensing 1049 00:40:09,880 --> 00:40:08,180 telescopes to actually look at the 1050 00:40:11,350 --> 00:40:09,890 surface of an exoplanet I'm not sure if 1051 00:40:13,900 --> 00:40:11,360 you've heard of this this project or not 1052 00:40:17,140 --> 00:40:13,910 yet and if you could speak to it for a 1053 00:40:20,890 --> 00:40:17,150 moment yes so so the idea is that you'd 1054 00:40:22,840 --> 00:40:20,900 use the gravity gravitational the Sun as 1055 00:40:25,030 --> 00:40:22,850 a gravitational land's name amplify the 1056 00:40:27,490 --> 00:40:25,040 signal from a distant planet and you'd 1057 00:40:30,970 --> 00:40:27,500 have to go to the focus of the Sun which 1058 00:40:32,590 --> 00:40:30,980 is about a hundred au away 100 1059 00:40:34,000 --> 00:40:32,600 astronomical units a hundred times the 1060 00:40:35,500 --> 00:40:34,010 distance between Earth and the Sun and 1061 00:40:37,570 --> 00:40:35,510 it would be quite a challenging 1062 00:40:38,920 --> 00:40:37,580 proposition to put a telescope there but 1063 00:40:41,830 --> 00:40:38,930 it would be a lot less challenging than 1064 00:40:45,280 --> 00:40:41,840 actually trying to undertake 1065 00:40:47,200 --> 00:40:45,290 interstellar flight and and also be much 1066 00:40:49,450 --> 00:40:47,210 much much quicker and so this is 1067 00:40:50,860 --> 00:40:49,460 something probably probably in the far 1068 00:40:53,830 --> 00:40:50,870 what we think of as a far future but not 1069 00:40:56,140 --> 00:40:53,840 nearly as far as say sending sending an 1070 00:40:58,980 --> 00:40:56,150 interstellar spacecraft to a neighboring 1071 00:41:01,420 --> 00:40:58,990 star so I think it's a really fun idea 1072 00:41:04,660 --> 00:41:01,430 to pick apart and think about and I 1073 00:41:06,310 --> 00:41:04,670 think ultimately this is how the science 1074 00:41:09,010 --> 00:41:06,320 is going to progress is that we are 1075 00:41:12,070 --> 00:41:09,020 going to sort of start start a survey of 1076 00:41:16,150 --> 00:41:12,080 our solar neighborhood for planets that 1077 00:41:17,440 --> 00:41:16,160 we believe are potentially habitable and 1078 00:41:19,960 --> 00:41:17,450 we're going to learn more and more about 1079 00:41:21,580 --> 00:41:19,970 those worlds as time goes on and once we 1080 00:41:23,350 --> 00:41:21,590 find them and once we find the first 1081 00:41:24,640 --> 00:41:23,360 putative bio signature you know we're 1082 00:41:26,020 --> 00:41:24,650 never going to forget about those plants 1083 00:41:28,690 --> 00:41:26,030 there's always going to go back and 1084 00:41:31,840 --> 00:41:28,700 refine our understanding of those worlds 1085 00:41:34,420 --> 00:41:31,850 and it's going to last for for as long 1086 00:41:37,690 --> 00:41:34,430 as we last as a species 1087 00:41:39,730 --> 00:41:37,700 awesome so kind of in that realm then I 1088 00:41:42,220 --> 00:41:39,740 want to go to a question from auto group 1089 00:41:44,680 --> 00:41:42,230 as well from Twitter who wants to know 1090 00:41:46,210 --> 00:41:44,690 about the significance of having the 1091 00:41:49,089 --> 00:41:46,220 James Webb Space Telescope when that 1092 00:41:50,790 --> 00:41:49,099 launches go out to a position known as 1093 00:41:54,460 --> 00:41:50,800 El to go out go out just pass the moon 1094 00:41:55,839 --> 00:41:54,470 and orbit out there compared to 1095 00:41:58,599 --> 00:41:55,849 something like Hubble that orbits the 1096 00:42:00,099 --> 00:41:58,609 earth yeah I mean so the James Webb 1097 00:42:03,190 --> 00:42:00,109 Space Telescope is exciting it's gonna 1098 00:42:07,020 --> 00:42:03,200 do a lot of general astrophysics not 1099 00:42:10,150 --> 00:42:07,030 just exoplanets but it has the capacity 1100 00:42:12,640 --> 00:42:10,160 potentially to probe some rock EXO 1101 00:42:14,829 --> 00:42:12,650 planetary atmospheres maybe if we get 1102 00:42:17,049 --> 00:42:14,839 lucky will detect things like carbon 1103 00:42:19,089 --> 00:42:17,059 dioxide in an exoplanet area atmosphere 1104 00:42:23,140 --> 00:42:19,099 find the first secondary outgassed 1105 00:42:25,210 --> 00:42:23,150 atmospheres and and just begin with a 1106 00:42:29,589 --> 00:42:25,220 very small number of targets to perhaps 1107 00:42:32,799 --> 00:42:29,599 constrain habitability on some but it is 1108 00:42:34,839 --> 00:42:32,809 limited in some ways but the reason why 1109 00:42:38,410 --> 00:42:34,849 we why we want to put it out out at l2 1110 00:42:42,390 --> 00:42:38,420 is is in part to to make sure it's cold 1111 00:42:44,589 --> 00:42:42,400 in part to avoid the light from earth 1112 00:42:45,579 --> 00:42:44,599 interfering with the observations it 1113 00:42:48,460 --> 00:42:45,589 does mean that there are a lot of 1114 00:42:51,520 --> 00:42:48,470 consumables on on on spacecraft and 1115 00:42:53,430 --> 00:42:51,530 therefore its life time his problem is 1116 00:42:56,730 --> 00:42:53,440 much more limited than that of Hubble 1117 00:42:59,220 --> 00:42:56,740 okay with Hubble 1118 00:43:00,570 --> 00:42:59,230 I actually work on an orbit still 1119 00:43:03,750 --> 00:43:00,580 looking forward to judge a vestido 1120 00:43:04,700 --> 00:43:03,760 should be a very awesome mission another 1121 00:43:08,460 --> 00:43:04,710 question 1122 00:43:10,890 --> 00:43:08,470 Twitter from Avani hedge 1123 00:43:12,900 --> 00:43:10,900 Avani wants to know and this is 1124 00:43:15,870 --> 00:43:12,910 interesting is it an advantage or a 1125 00:43:18,390 --> 00:43:15,880 disadvantage for us to understand the 1126 00:43:20,730 --> 00:43:18,400 diversity of life on earth when we're in 1127 00:43:23,880 --> 00:43:20,740 this quest to understand or to find life 1128 00:43:26,850 --> 00:43:23,890 elsewhere I I have to think it's an 1129 00:43:29,910 --> 00:43:26,860 advantage you know if we we you know we 1130 00:43:31,980 --> 00:43:29,920 we are limited by the fact that we we 1131 00:43:33,690 --> 00:43:31,990 likely have one origin of life to work 1132 00:43:35,640 --> 00:43:33,700 with in our solar system as the origin 1133 00:43:38,460 --> 00:43:35,650 on on earth perhaps we have other 1134 00:43:39,840 --> 00:43:38,470 origins in the future when we probe the 1135 00:43:43,050 --> 00:43:39,850 subsurface of Mars with the subsurface 1136 00:43:45,240 --> 00:43:43,060 of Europa Enceladus but for now we have 1137 00:43:47,609 --> 00:43:45,250 one origin of life and we have all the 1138 00:43:49,380 --> 00:43:47,619 permutations that life has taken but 1139 00:43:52,440 --> 00:43:49,390 there is a concept called convergent 1140 00:43:54,390 --> 00:43:52,450 evolution that's existent it exists in 1141 00:43:55,830 --> 00:43:54,400 multiple clades that are relatively 1142 00:43:58,410 --> 00:43:55,840 unrelated on earth although they do 1143 00:44:00,450 --> 00:43:58,420 share a common origin they independently 1144 00:44:02,820 --> 00:44:00,460 evolved the same either metabolism or 1145 00:44:05,340 --> 00:44:02,830 the same adaptation the same morphology 1146 00:44:07,050 --> 00:44:05,350 to meet the same problem and so 1147 00:44:08,640 --> 00:44:07,060 understanding the diversity of life on 1148 00:44:10,620 --> 00:44:08,650 earth does give us a huge amount of 1149 00:44:12,140 --> 00:44:10,630 information about the possibilities for 1150 00:44:15,240 --> 00:44:12,150 life elsewhere because we do believe 1151 00:44:17,040 --> 00:44:15,250 physical chemical conditions that 1152 00:44:20,910 --> 00:44:17,050 existed on early Earth will exist 1153 00:44:21,900 --> 00:44:20,920 elsewhere in our universe yeah it seems 1154 00:44:24,960 --> 00:44:21,910 like you know convergent evolution 1155 00:44:27,270 --> 00:44:24,970 should lead to some similar things if 1156 00:44:28,590 --> 00:44:27,280 there is life out there but maybe not 1157 00:44:30,420 --> 00:44:28,600 exactly you know what we see in movies 1158 00:44:31,770 --> 00:44:30,430 right with with two arms two legs you 1159 00:44:35,040 --> 00:44:31,780 know two eyes that kind of thing but 1160 00:44:38,160 --> 00:44:35,050 maybe arms or fins or wings are common 1161 00:44:41,310 --> 00:44:38,170 for some work isms we have a question 1162 00:44:43,770 --> 00:44:41,320 from Austin Dieng on Facebook Austin 1163 00:44:45,480 --> 00:44:43,780 wants to know what methods do we do we 1164 00:44:50,820 --> 00:44:45,490 have to distinguish bio signatures that 1165 00:44:52,800 --> 00:44:50,830 are not a biotic Lea produced yeah so so 1166 00:44:56,460 --> 00:44:52,810 one is one is to fingerprint the abiotic 1167 00:44:57,720 --> 00:44:56,470 process so so if we think that it's from 1168 00:44:59,640 --> 00:44:57,730 this a photo chemistry there breaking 1169 00:45:01,590 --> 00:44:59,650 apart of say the co2 molecule into 1170 00:45:02,430 --> 00:45:01,600 oxygen and carbon monoxide we'd expect 1171 00:45:04,680 --> 00:45:02,440 there to be a lot of carbon monoxide 1172 00:45:06,930 --> 00:45:04,690 alongside that abiotic oxygen so that's 1173 00:45:09,030 --> 00:45:06,940 one idea that you could fingerprint the 1174 00:45:09,650 --> 00:45:09,040 abiotic process another idea is that if 1175 00:45:11,270 --> 00:45:09,660 you have a mass 1176 00:45:12,589 --> 00:45:11,280 the oxygen atmosphere from this runaway 1177 00:45:14,029 --> 00:45:12,599 process I mentioned earlier where the 1178 00:45:15,500 --> 00:45:14,039 hydrogen all escapes the oxygen is left 1179 00:45:17,809 --> 00:45:15,510 behind you probably would end up 1180 00:45:20,510 --> 00:45:17,819 actually with a lot more oxygen if you 1181 00:45:22,900 --> 00:45:20,520 were left with any then then exists on 1182 00:45:26,240 --> 00:45:22,910 earth today and and oxygen has these 1183 00:45:27,829 --> 00:45:26,250 molecular features that only are only 1184 00:45:29,299 --> 00:45:27,839 strong when when when the oxygen 1185 00:45:30,859 --> 00:45:29,309 abundance is very high because they're 1186 00:45:33,170 --> 00:45:30,869 due to collisions between oxygen 1187 00:45:34,970 --> 00:45:33,180 molecules so that's one way is to 1188 00:45:37,640 --> 00:45:34,980 fingerprint the abiotic process another 1189 00:45:40,339 --> 00:45:37,650 way is to look for the disequilibrium as 1190 00:45:41,990 --> 00:45:40,349 I mentioned so that you would not expect 1191 00:45:44,809 --> 00:45:42,000 the co-occurrence of certain gases 1192 00:45:47,150 --> 00:45:44,819 together the fact that Earth today has 1193 00:45:50,089 --> 00:45:47,160 oxygen ozone yes but also methane and 1194 00:45:52,670 --> 00:45:50,099 nitrous oxide is indicative of this 1195 00:45:54,440 --> 00:45:52,680 non-equilibrium process that's driving 1196 00:45:55,970 --> 00:45:54,450 that's life that's driving the 1197 00:45:57,559 --> 00:45:55,980 disability program between the gases 1198 00:45:59,630 --> 00:45:57,569 additionally we have something called 1199 00:46:02,510 --> 00:45:59,640 the vegetation red edge on on earth 1200 00:46:04,670 --> 00:46:02,520 which is this contrast between a 1201 00:46:07,180 --> 00:46:04,680 chlorophyll absorption at visible 1202 00:46:08,900 --> 00:46:07,190 wavelengths and very reflective 1203 00:46:11,240 --> 00:46:08,910 vegetation at near-infrared wavelengths 1204 00:46:13,700 --> 00:46:11,250 it's used this effect is used to map 1205 00:46:15,680 --> 00:46:13,710 vegetation on earth it exists in the 1206 00:46:18,200 --> 00:46:15,690 discourage of our planet to some extent 1207 00:46:19,849 --> 00:46:18,210 and it's another tool in the toolbox 1208 00:46:21,920 --> 00:46:19,859 potentially for fingerprinting 1209 00:46:24,109 --> 00:46:21,930 biospheres on other planets we don't 1210 00:46:26,779 --> 00:46:24,119 necessarily expect that to be the same 1211 00:46:29,990 --> 00:46:26,789 on on on other planets but it could be 1212 00:46:31,910 --> 00:46:30,000 there could be a similar signature where 1213 00:46:34,730 --> 00:46:31,920 you have this spectral break between 1214 00:46:37,400 --> 00:46:34,740 absorption and reflection that indicates 1215 00:46:38,900 --> 00:46:37,410 a biological pigment and so what we 1216 00:46:42,289 --> 00:46:38,910 really want to see is this multiple 1217 00:46:44,180 --> 00:46:42,299 lines of evidence that converge on the 1218 00:46:45,890 --> 00:46:44,190 bio signature interpretation so we rule 1219 00:46:47,510 --> 00:46:45,900 out the abiotic processes and then we 1220 00:46:51,589 --> 00:46:47,520 rule in the biology by looking for the 1221 00:46:54,289 --> 00:46:51,599 disk equilibrium on that so you know we 1222 00:46:56,180 --> 00:46:54,299 started off this episode with that image 1223 00:46:58,279 --> 00:46:56,190 of Lake Hillier being that bubblegum 1224 00:47:00,589 --> 00:46:58,289 pink coloration from this organism that 1225 00:47:02,990 --> 00:47:00,599 produces carotenoids you know these 1226 00:47:04,849 --> 00:47:03,000 these pigments I wonder you know just 1227 00:47:06,529 --> 00:47:04,859 for fun do you think we're going to 1228 00:47:09,109 --> 00:47:06,539 we're going to see out there in the 1229 00:47:11,930 --> 00:47:09,119 cosmos a bunch of planets that have like 1230 00:47:13,670 --> 00:47:11,940 weird colorations to them because of an 1231 00:47:15,799 --> 00:47:13,680 abundance of organisms producing 1232 00:47:17,900 --> 00:47:15,809 pigments like that yeah I mean that's 1233 00:47:20,180 --> 00:47:17,910 one one possibility is that there are 1234 00:47:21,680 --> 00:47:20,190 pigments that are that it's not just you 1235 00:47:24,350 --> 00:47:21,690 know green chlorophyll pigments 1236 00:47:26,480 --> 00:47:24,360 out there and so the there's there's a 1237 00:47:27,890 --> 00:47:26,490 den under Nellie Ella algae that 1238 00:47:30,350 --> 00:47:27,900 produced the carotenoid pigments and 1239 00:47:35,090 --> 00:47:30,360 then are also archaea that have pigments 1240 00:47:38,090 --> 00:47:35,100 like bacteria Ribera barren and and and 1241 00:47:41,990 --> 00:47:38,100 up since rhodopsins are kind of pigment 1242 00:47:45,380 --> 00:47:42,000 that generates energy from from the Sun 1243 00:47:47,990 --> 00:47:45,390 but is not a chlorophyll so it's driving 1244 00:47:50,450 --> 00:47:48,000 the production of energy by creating 1245 00:47:51,920 --> 00:47:50,460 this proton gradient that then drives 1246 00:47:54,020 --> 00:47:51,930 the production of ATP which is the 1247 00:47:55,280 --> 00:47:54,030 energy currency of a cell right now we 1248 00:47:57,380 --> 00:47:55,290 don't know of any organism that uses 1249 00:47:59,180 --> 00:47:57,390 this rhodopsin pigment to fix carbon but 1250 00:48:00,950 --> 00:47:59,190 it can make energy and so you might 1251 00:48:02,510 --> 00:48:00,960 imagine that there are other organisms 1252 00:48:04,310 --> 00:48:02,520 out there in the universe that are using 1253 00:48:06,080 --> 00:48:04,320 similar pigments to generate energy and 1254 00:48:08,750 --> 00:48:06,090 perhaps they'll have a spectral impact 1255 00:48:11,450 --> 00:48:08,760 on their planet be so cool to find a 1256 00:48:13,370 --> 00:48:11,460 pink world or a purple world or you know 1257 00:48:15,830 --> 00:48:13,380 other colorations besides our little 1258 00:48:18,830 --> 00:48:15,840 blue marble we have a question from 1259 00:48:20,090 --> 00:48:18,840 Satyam Tiwari on second net and this 1260 00:48:22,100 --> 00:48:20,100 kind of goes back to we were discussing 1261 00:48:23,540 --> 00:48:22,110 you know with conditions of life here on 1262 00:48:24,800 --> 00:48:23,550 earth and this idea of convergent 1263 00:48:26,860 --> 00:48:24,810 evolution leading to some things that 1264 00:48:29,690 --> 00:48:26,870 are similar but also being different 1265 00:48:32,030 --> 00:48:29,700 saaaam wants to know would life on 1266 00:48:36,160 --> 00:48:32,040 exoplanets evolve in similar conditions 1267 00:48:40,250 --> 00:48:36,170 or chemistry's as we find on earth today 1268 00:48:42,260 --> 00:48:40,260 well yes so so the earth today has a 1269 00:48:44,600 --> 00:48:42,270 wide variety of environments and so this 1270 00:48:46,190 --> 00:48:44,610 speaks speaks to one of the previous 1271 00:48:47,810 --> 00:48:46,200 questions that we have we have 1272 00:48:50,120 --> 00:48:47,820 environments that are low in pH that are 1273 00:48:51,740 --> 00:48:50,130 high in PSO acid and alkaline and high 1274 00:48:53,120 --> 00:48:51,750 in salt and low in salt and high in 1275 00:48:55,400 --> 00:48:53,130 temperature and low in temperature and 1276 00:48:56,570 --> 00:48:55,410 so we have this huge menu of 1277 00:48:58,700 --> 00:48:56,580 environments on earth that life is 1278 00:49:00,260 --> 00:48:58,710 adapted to and we believe that that 1279 00:49:02,450 --> 00:49:00,270 diversity is going to be recapitulated 1280 00:49:05,120 --> 00:49:02,460 on exoplanets that there will be a wide 1281 00:49:07,640 --> 00:49:05,130 diversity of environments and niches for 1282 00:49:09,530 --> 00:49:07,650 for life and so studying these 1283 00:49:11,360 --> 00:49:09,540 environments is really critical both to 1284 00:49:13,190 --> 00:49:11,370 understanding the history of life on 1285 00:49:14,600 --> 00:49:13,200 Earth where certain niche environments 1286 00:49:17,180 --> 00:49:14,610 today might have actually dominated in 1287 00:49:19,400 --> 00:49:17,190 the past to extrapolating those two to 1288 00:49:21,830 --> 00:49:19,410 other planets where where again the 1289 00:49:23,300 --> 00:49:21,840 conditions may be more similar to what 1290 00:49:25,430 --> 00:49:23,310 are in each conditions today or what are 1291 00:49:28,640 --> 00:49:25,440 more similar to ancient conditions in 1292 00:49:30,770 --> 00:49:28,650 the Earth's ancient past mmm that's 1293 00:49:32,150 --> 00:49:30,780 awesome I do want to so we are getting 1294 00:49:34,280 --> 00:49:32,160 close to the hour now 1295 00:49:36,290 --> 00:49:34,290 I think thank you to everyone who asked 1296 00:49:37,849 --> 00:49:36,300 questions I am gonna pick one of the 1297 00:49:39,830 --> 00:49:37,859 questions that remains yet as my 1298 00:49:40,640 --> 00:49:39,840 favorite one to ask this one comes from 1299 00:49:43,310 --> 00:49:40,650 my co-host 1300 00:49:46,130 --> 00:49:43,320 Sanjoy on sega nets and really wants to 1301 00:49:48,800 --> 00:49:46,140 know dr. speedermen how do you balance 1302 00:49:51,950 --> 00:49:48,810 the demands of science with raising a 1303 00:49:54,920 --> 00:49:51,960 young family right the great question 1304 00:49:57,380 --> 00:49:54,930 saundra yes I have I have two sons one 1305 00:50:00,349 --> 00:49:57,390 one was just born last month and one is 1306 00:50:03,349 --> 00:50:00,359 two and a half years old and and an 1307 00:50:05,630 --> 00:50:03,359 intelligent and lovely partner and so 1308 00:50:08,090 --> 00:50:05,640 and so yeah I think I think it's 1309 00:50:12,230 --> 00:50:08,100 incredibly important to prioritize your 1310 00:50:13,820 --> 00:50:12,240 family I love spending time with my kids 1311 00:50:17,150 --> 00:50:13,830 and playing with my kids and and they'll 1312 00:50:19,760 --> 00:50:17,160 always always come first for me but I 1313 00:50:21,920 --> 00:50:19,770 think I see I see is kind of my 1314 00:50:24,500 --> 00:50:21,930 responsibility to instill the Wonder in 1315 00:50:27,470 --> 00:50:24,510 my kids that I feel for my science and 1316 00:50:29,330 --> 00:50:27,480 that also my parents helped me with and 1317 00:50:32,270 --> 00:50:29,340 we are all kind of this continuation 1318 00:50:34,490 --> 00:50:32,280 we're all part of the same universe and 1319 00:50:36,140 --> 00:50:34,500 so understanding that and helping my 1320 00:50:38,750 --> 00:50:36,150 kids understand that in the future is 1321 00:50:40,310 --> 00:50:38,760 really important to me that we can all 1322 00:50:41,810 --> 00:50:40,320 share in this beautiful universe that we 1323 00:50:44,930 --> 00:50:41,820 live in where we can think about finding 1324 00:50:46,400 --> 00:50:44,940 life elsewhere and and I and and and and 1325 00:50:48,580 --> 00:50:46,410 this is all to say that everything is 1326 00:50:52,220 --> 00:50:48,590 related you know if you have to bring 1327 00:50:55,400 --> 00:50:52,230 compassion and love into your job and in 1328 00:50:57,890 --> 00:50:55,410 and into raising your family not 1329 00:50:59,510 --> 00:50:57,900 beautiful Eddie thank you so much for 1330 00:51:02,210 --> 00:50:59,520 joining us it's been great having you on 1331 00:51:04,849 --> 00:51:02,220 the show for everyone watching here's a 1332 00:51:06,530 --> 00:51:04,859 little call for action for all of you so 1333 00:51:09,170 --> 00:51:06,540 with upcoming missions now for looking 1334 00:51:10,010 --> 00:51:09,180 for signs of life in our solar system as 1335 00:51:12,230 --> 00:51:10,020 well as some of these upcoming 1336 00:51:14,349 --> 00:51:12,240 next-generation and telescopes that dr. 1337 00:51:16,880 --> 00:51:14,359 Street Irma mentioned during our episode 1338 00:51:19,580 --> 00:51:16,890 do you think we're most likely going to 1339 00:51:23,060 --> 00:51:19,590 find life on a world in our solar system 1340 00:51:24,349 --> 00:51:23,070 or from an exoplanet first and if you 1341 00:51:26,599 --> 00:51:24,359 have any thoughts on that feel free to 1342 00:51:31,960 --> 00:51:26,609 discuss amongst yourselves or you can 1343 00:51:36,890 --> 00:51:34,940 astrobiologist and use hashtag ask aster 1344 00:51:38,530 --> 00:51:36,900 bio on Twitter I get involved in the 1345 00:51:41,270 --> 00:51:38,540 conversation we'd love to have more 1346 00:51:42,540 --> 00:51:41,280 conversations with you Eddie thank you 1347 00:51:44,940 --> 00:51:42,550 so much for joining us thank 1348 00:51:47,220 --> 00:51:44,950 so much Graham it's great to be here and 1349 00:51:51,360 --> 00:51:47,230 for everyone watching right now Mike's 1350 00:51:53,940 --> 00:51:51,370 gonna bring up on to the display for you 1351 00:51:57,030 --> 00:51:53,950 to see how to subscribe to the email 1352 00:52:00,060 --> 00:51:57,040 list for NASA Astrobiology to loop into 1353 00:52:02,580 --> 00:52:00,070 upcoming episodes and more info and so 1354 00:52:03,690 --> 00:52:02,590 you can see that right now and then you 1355 00:52:08,210 --> 00:52:03,700 know to all of you thank you for joining 1356 00:52:48,810 --> 00:52:08,220 and as always remember stay curious