1 00:00:41,950 --> 00:00:39,259 on the surface of an average planet 2 00:00:44,810 --> 00:00:41,960 circling an ordinary yellow star an 3 00:00:52,520 --> 00:00:44,820 advanced intelligence searches the skies 4 00:00:55,039 --> 00:00:52,530 for evidence of life directed by even 5 00:00:58,009 --> 00:00:55,049 higher intelligence machines with brains 6 00:01:00,049 --> 00:00:58,019 of silicon patiently sift through faith 7 00:01:02,090 --> 00:01:00,059 shards of radio data for the 8 00:01:09,580 --> 00:01:02,100 unmistakable signal that will indicate 9 00:01:12,320 --> 00:01:09,590 the first sign of life beyond Earth in 10 00:01:14,480 --> 00:01:12,330 1959 physicist Philip Morrison was 11 00:01:17,770 --> 00:01:14,490 co-author of the first scientific paper 12 00:01:20,029 --> 00:01:17,780 to suggest a strategy for such a search 13 00:01:22,190 --> 00:01:20,039 no is an answer to a very simple 14 00:01:25,580 --> 00:01:22,200 question are we alone as conscious 15 00:01:28,999 --> 00:01:25,590 beings in this entire buzzing four 16 00:01:31,580 --> 00:01:29,009 hundred billion star galaxy one of ten 17 00:01:34,940 --> 00:01:31,590 to the tenth other galaxies it seems 18 00:01:37,060 --> 00:01:34,950 pretty implausible it's an enormous task 19 00:01:39,859 --> 00:01:37,070 to search the skies for intelligent life 20 00:01:42,709 --> 00:01:39,869 looking for a golden needle in a huge 21 00:01:44,660 --> 00:01:42,719 cosmic haystack but steady the search 22 00:01:47,060 --> 00:01:44,670 for extraterrestrial intelligence has 23 00:01:50,149 --> 00:01:47,070 come a long way since early experiments 24 00:01:52,760 --> 00:01:50,159 by young radio astronomer Frank Drake in 25 00:01:55,789 --> 00:01:52,770 1960 Drake made the first radio search 26 00:01:58,130 --> 00:01:55,799 from Green Bank West Virginia he called 27 00:02:02,779 --> 00:01:58,140 it Ozma after a princess from the 28 00:02:04,700 --> 00:02:02,789 fictional Land of Oz now plans for the 29 00:02:07,069 --> 00:02:04,710 most sophisticated SETI search ever 30 00:02:09,289 --> 00:02:07,079 focus on the goldstone deep space 31 00:02:12,349 --> 00:02:09,299 communication complex in California's 32 00:02:15,080 --> 00:02:12,359 Mojave Desert it is the site of tests 33 00:02:17,780 --> 00:02:15,090 for a possible future NASA project one 34 00:02:20,000 --> 00:02:17,790 not yet funded the full-scale NASA 35 00:02:22,130 --> 00:02:20,010 system when operational in the next 36 00:02:24,319 --> 00:02:22,140 decade would be billions of times more 37 00:02:26,250 --> 00:02:24,329 powerful than the sum of all previous 38 00:02:29,230 --> 00:02:26,260 searches 39 00:02:31,630 --> 00:02:29,240 for carl sagan a proponent of Seti for 40 00:02:34,000 --> 00:02:31,640 many years this technical progress has 41 00:02:36,900 --> 00:02:34,010 made the present unique for the first 42 00:02:40,450 --> 00:02:36,910 time we're mustering substantial 43 00:02:42,910 --> 00:02:40,460 sophisticated serious scientific 44 00:02:44,350 --> 00:02:42,920 searches for for extraterrestrial 45 00:02:47,350 --> 00:02:44,360 intelligence has never been a time like 46 00:02:49,390 --> 00:02:47,360 that perform so there is some chance 47 00:02:53,500 --> 00:02:49,400 that in the next few decades we will get 48 00:02:56,190 --> 00:02:53,510 a signal from some spectacularly distant 49 00:02:58,330 --> 00:02:56,200 spectacularly exotic civilization and 50 00:03:26,780 --> 00:02:58,340 everything on earth will as a 51 00:03:32,509 --> 00:03:30,380 how why when and whether to search for 52 00:03:35,449 --> 00:03:32,519 life beyond Earth has been debated for 53 00:03:39,339 --> 00:03:35,459 centuries deciding what sort of signal 54 00:03:42,110 --> 00:03:39,349 to look for in the skies is no easy task 55 00:03:43,640 --> 00:03:42,120 NASA's proposed search focuses on radio 56 00:03:46,309 --> 00:03:43,650 a portion of the electromagnetic 57 00:03:48,670 --> 00:03:46,319 spectrum where nature produces the least 58 00:03:51,679 --> 00:03:48,680 interference for any intelligent signal 59 00:03:54,050 --> 00:03:51,689 the plan is to use existing radio 60 00:03:55,449 --> 00:03:54,060 antennas and combine them with advanced 61 00:03:58,420 --> 00:03:55,459 computer hardware and software 62 00:04:01,129 --> 00:03:58,430 specifically designed for the task 63 00:04:03,229 --> 00:04:01,139 signal processing equipment suitable for 64 00:04:05,360 --> 00:04:03,239 SETI is constantly becoming more 65 00:04:08,800 --> 00:04:05,370 powerful and more efficient but also 66 00:04:12,140 --> 00:04:08,810 cheaper and smaller than ever before in 67 00:04:14,449 --> 00:04:12,150 the mid 1990s NASA hopes to deploy it 68 00:04:16,580 --> 00:04:14,459 systems in a relatively low cost ten 69 00:04:18,979 --> 00:04:16,590 years search that will for the first 70 00:04:20,810 --> 00:04:18,989 time systematically explore all the 71 00:04:23,210 --> 00:04:20,820 radio frequencies and directions on the 72 00:04:30,950 --> 00:04:23,220 sky that researchers think might reveal 73 00:04:32,300 --> 00:04:30,960 a signal my name is Jill tarter I'm an 74 00:04:34,370 --> 00:04:32,310 astronomer from the University of 75 00:04:35,960 --> 00:04:34,380 California at Berkeley and I work with 76 00:04:38,689 --> 00:04:35,970 colleagues from NASA's Ames Research 77 00:04:40,790 --> 00:04:38,699 Center the Jet Propulsion Laboratory and 78 00:04:43,010 --> 00:04:40,800 the SETI Institute to help design the 79 00:04:47,390 --> 00:04:43,020 special purpose tools needed to do SETI 80 00:04:49,550 --> 00:04:47,400 properly over the years I've worked at 81 00:04:51,980 --> 00:04:49,560 many radio telescopes like this one at 82 00:04:53,870 --> 00:04:51,990 knole say in france trying to adapt 83 00:04:57,110 --> 00:04:53,880 existing equipment to this difficult 84 00:05:00,110 --> 00:04:57,120 task these efforts I hope will soon be 85 00:05:02,060 --> 00:05:00,120 eclipsed by the planned NASA system some 86 00:05:05,980 --> 00:05:02,070 parts of which may eventually be placed 87 00:05:10,730 --> 00:05:08,290 contemporary city is a science a 88 00:05:13,160 --> 00:05:10,740 discipline which transforms humanity's 89 00:05:15,610 --> 00:05:13,170 age-old speculations about life and 90 00:05:18,230 --> 00:05:15,620 universe into experimental reality 91 00:05:19,760 --> 00:05:18,240 steady pioneer Frank Drake came up with 92 00:05:22,400 --> 00:05:19,770 a way to organize our developing 93 00:05:24,200 --> 00:05:22,410 knowledge and current ignorance SETI 94 00:05:26,270 --> 00:05:24,210 scientists often use what's called the 95 00:05:28,820 --> 00:05:26,280 Drake Equation to illuminate the 96 00:05:30,470 --> 00:05:28,830 necessary conditions for contact and to 97 00:05:34,160 --> 00:05:30,480 provide a rough estimate of the number 98 00:05:37,070 --> 00:05:34,170 of other civilizations the existence of 99 00:05:43,180 --> 00:05:37,080 other technical civilizations depends 100 00:05:53,350 --> 00:05:49,760 comparative planetology biochemistry the 101 00:05:56,870 --> 00:05:53,360 role of intelligence in evolution 102 00:05:59,900 --> 00:05:56,880 technology and the fate of technical 103 00:06:01,700 --> 00:05:59,910 civilizations so SETI becomes a way to 104 00:06:03,650 --> 00:06:01,710 test our theories of the origin and 105 00:06:07,250 --> 00:06:03,660 evolution of the universe and the place 106 00:06:08,840 --> 00:06:07,260 of life within it some factors in the 107 00:06:12,230 --> 00:06:08,850 Drake Equation are well determined 108 00:06:14,750 --> 00:06:12,240 others are not we're pretty sure our 109 00:06:16,820 --> 00:06:14,760 galaxy has about 400 billion stars and 110 00:06:19,370 --> 00:06:16,830 maybe ten percent of them will shine 111 00:06:21,110 --> 00:06:19,380 long enough for life to evolve and we 112 00:06:24,530 --> 00:06:21,120 understand something of a life cycle of 113 00:06:27,260 --> 00:06:24,540 those stars we know that it required 114 00:06:28,970 --> 00:06:27,270 colossal supernova explosions to 115 00:06:31,460 --> 00:06:28,980 transform the simple elements produced 116 00:06:35,830 --> 00:06:31,470 in the Big Bang into the heavy elements 117 00:06:38,530 --> 00:06:35,840 that form rocky planets and we ourselves 118 00:06:40,570 --> 00:06:38,540 and we have taken the first steps in 119 00:06:43,659 --> 00:06:40,580 understanding the chemical origin of 120 00:06:45,879 --> 00:06:43,669 life and the principles of evolution but 121 00:06:48,219 --> 00:06:45,889 as yet we found no definitive proof of 122 00:06:50,200 --> 00:06:48,229 solar systems beyond our own though 123 00:06:51,939 --> 00:06:50,210 recent observations of the disk of 124 00:06:54,250 --> 00:06:51,949 matter around the nearby star beta 125 00:06:57,310 --> 00:06:54,260 Pictoris suggests the planets they 126 00:06:59,770 --> 00:06:57,320 become in our own solar system we have 127 00:07:02,290 --> 00:06:59,780 found no signs of advanced life though 128 00:07:04,870 --> 00:07:02,300 planets like Mars from the large moons 129 00:07:06,730 --> 00:07:04,880 like Europa and Titan may have provided 130 00:07:09,430 --> 00:07:06,740 suitable environments for life in the 131 00:07:14,140 --> 00:07:09,440 past or may do in the future and seem 132 00:07:16,120 --> 00:07:14,150 worth further exploratory missions so 133 00:07:18,150 --> 00:07:16,130 far we have detected no signals from 134 00:07:20,800 --> 00:07:18,160 other civilizations around other stars 135 00:07:23,560 --> 00:07:20,810 using technologies which could make them 136 00:07:25,719 --> 00:07:23,570 visible across the light-years and we 137 00:07:27,909 --> 00:07:25,729 cannot predict whether civilizations 138 00:07:30,310 --> 00:07:27,919 with advanced technology will perish 139 00:07:32,500 --> 00:07:30,320 quickly or learn to use it to explore 140 00:07:35,500 --> 00:07:32,510 the universe and thrive for the lifetime 141 00:07:37,659 --> 00:07:35,510 of their star some people look at the 142 00:07:39,900 --> 00:07:37,669 seven conditions Drake proposed and see 143 00:07:42,550 --> 00:07:39,910 a weak chain that could easily be broken 144 00:07:45,250 --> 00:07:42,560 Drake himself thinks there could be many 145 00:07:47,409 --> 00:07:45,260 thousands of civilizations with whom we 146 00:07:49,900 --> 00:07:47,419 could communicate in the Milky Way alone 147 00:07:51,690 --> 00:07:49,910 we take the solar system which we know 148 00:07:54,640 --> 00:07:51,700 has happened and the life on Earth is 149 00:07:56,800 --> 00:07:54,650 typical and as far as we know it is 150 00:07:59,800 --> 00:07:56,810 typical we know of nothing no freakish 151 00:08:01,750 --> 00:07:59,810 event that was required for us with our 152 00:08:04,870 --> 00:08:01,760 motorcycles and our video tape recorders 153 00:08:07,089 --> 00:08:04,880 to exist SETI researchers such as 154 00:08:08,529 --> 00:08:07,099 Harvard's Paul Horowitz doubt that the 155 00:08:10,920 --> 00:08:08,539 question of other life in the universe 156 00:08:12,850 --> 00:08:10,930 will ever be answered in the abstract 157 00:08:14,560 --> 00:08:12,860 people have argued for a long time about 158 00:08:16,029 --> 00:08:14,570 the odds what are the probabilities that 159 00:08:19,029 --> 00:08:16,039 there's life elsewhere in the universe 160 00:08:21,129 --> 00:08:19,039 and lacking any data they're nothing but 161 00:08:22,659 --> 00:08:21,139 arguments and you can argue yourself 162 00:08:24,940 --> 00:08:22,669 blue in the face but if you want to 163 00:08:27,790 --> 00:08:24,950 answer this question you're gonna have 164 00:08:29,469 --> 00:08:27,800 to do the experiment but how can you do 165 00:08:32,170 --> 00:08:29,479 the experiment what is the right 166 00:08:35,140 --> 00:08:32,180 experiment over interstellar distances 167 00:08:37,269 --> 00:08:35,150 there's little sign of Earth the Sun 168 00:08:38,660 --> 00:08:37,279 outshines the planet by more than a 169 00:08:40,370 --> 00:08:38,670 billion to one 170 00:08:42,590 --> 00:08:40,380 that's one reason we've not yet seen 171 00:08:45,200 --> 00:08:42,600 planets around other stars with even the 172 00:08:47,240 --> 00:08:45,210 largest optical telescopes it's rather 173 00:08:50,690 --> 00:08:47,250 like trying to see a firefly perched on 174 00:08:53,150 --> 00:08:50,700 the rim of a searchlight but at radio 175 00:08:55,940 --> 00:08:53,160 wavelengths at certain times and certain 176 00:08:58,370 --> 00:08:55,950 frequencies Earth's technology outshines 177 00:09:01,610 --> 00:08:58,380 all other sources in the solar system by 178 00:09:03,580 --> 00:09:01,620 nearly a million to one the carrier 179 00:09:05,960 --> 00:09:03,590 waves of Earth's radio and television 180 00:09:09,260 --> 00:09:05,970 broadcasts leak outward in a spherical 181 00:09:13,220 --> 00:09:09,270 shell and could be detected by distant 182 00:09:15,470 --> 00:09:13,230 civilizations radio signals travel at 183 00:09:18,830 --> 00:09:15,480 the speed of light the fastest velocity 184 00:09:21,710 --> 00:09:18,840 possible in contrast pioneer 10 has been 185 00:09:24,050 --> 00:09:21,720 traveling for nine years to cover some 4 186 00:09:26,200 --> 00:09:24,060 billion miles but its signal arrives 187 00:09:29,120 --> 00:09:26,210 back here on earth in just five hours 188 00:09:32,030 --> 00:09:29,130 that's one reason NASA researchers think 189 00:09:34,160 --> 00:09:32,040 it is communication not physical travel 190 00:09:37,100 --> 00:09:34,170 that makes most sense for all species 191 00:09:39,440 --> 00:09:37,110 everywhere in the universe earth's most 192 00:09:44,680 --> 00:09:39,450 sensitive antennas could detect strong 193 00:09:50,420 --> 00:09:47,260 traveling for just five light-hours 194 00:09:52,820 --> 00:09:50,430 pioneer tens very weak signal is being 195 00:09:55,760 --> 00:09:52,830 used to test NASA's prototype detectors 196 00:09:58,400 --> 00:09:55,770 back here on earth Barney Oliver chief 197 00:09:59,930 --> 00:09:58,410 up NASA's SETI office looking for a 198 00:10:03,050 --> 00:09:59,940 signal now it's coming from the Pioneer 199 00:10:04,730 --> 00:10:03,060 spacecraft which is now outside the 200 00:10:09,700 --> 00:10:04,740 solar system that's beyond the orbit of 201 00:10:13,070 --> 00:10:09,710 Neptune its carrier is a 1 watt signal 202 00:10:15,650 --> 00:10:13,080 and that is about the fun what one 203 00:10:18,020 --> 00:10:15,660 twentieth of the energy of a candle 204 00:10:21,890 --> 00:10:18,030 burning so we're picking up a really 205 00:10:24,050 --> 00:10:21,900 small signal indeed we succeed the Naza 206 00:10:26,870 --> 00:10:24,060 effort has united Barney Oliver and 207 00:10:28,910 --> 00:10:26,880 other longtime City proponents with the 208 00:10:31,550 --> 00:10:28,920 younger generation of computer builders 209 00:10:34,940 --> 00:10:31,560 and programmers including Kent colors 210 00:10:37,150 --> 00:10:34,950 who despite being blind has worked on 211 00:10:40,580 --> 00:10:37,160 the statistics of pattern recognition 212 00:10:42,680 --> 00:10:40,590 pioneer 10 is simply a very good example 213 00:10:45,410 --> 00:10:42,690 of the kind of signal that we might 214 00:10:47,540 --> 00:10:45,420 detect first of all although it's kind 215 00:10:49,430 --> 00:10:47,550 of close in interstellar terms it's a 216 00:10:52,079 --> 00:10:49,440 very weak one would expect that a 217 00:10:53,970 --> 00:10:52,089 civilization would be farther away and 218 00:10:57,119 --> 00:10:53,980 hunger it's near the limit of our 219 00:11:01,619 --> 00:10:57,129 detection it's also a good example of a 220 00:11:05,340 --> 00:11:01,629 signal that might be used as beacon I'm 221 00:11:07,519 --> 00:11:05,350 gonna go upper hurts just let's see what 222 00:11:09,540 --> 00:11:07,529 happens here the test was successful 223 00:11:11,249 --> 00:11:09,550 even though the rotation of the earth 224 00:11:13,259 --> 00:11:11,259 and its motion through the galaxy 225 00:11:15,150 --> 00:11:13,269 continuously changes the frequency of 226 00:11:19,019 --> 00:11:15,160 Pioneer signal over time there's a 227 00:11:21,119 --> 00:11:19,029 promising candidate right here laughs a 228 00:11:26,220 --> 00:11:21,129 wait for a few more spectra to see if it 229 00:11:29,340 --> 00:11:26,230 does yes I think that's it this right 230 00:11:32,160 --> 00:11:29,350 line do you see going slanting down the 231 00:11:37,650 --> 00:11:32,170 screen is the signal from the pioneer 10 232 00:11:40,259 --> 00:11:37,660 spacecraft now if you look at other 233 00:11:43,199 --> 00:11:40,269 means of communication or making contact 234 00:11:45,569 --> 00:11:43,209 you have to send something you can't 235 00:11:47,999 --> 00:11:45,579 just think about it you have to send 236 00:11:49,829 --> 00:11:48,009 something and we've investigated all the 237 00:11:51,989 --> 00:11:49,839 known particles and it's certainly true 238 00:11:56,280 --> 00:11:51,999 that electromagnetic waves or photons 239 00:11:57,780 --> 00:11:56,290 are hands down the best medium to use so 240 00:11:59,850 --> 00:11:57,790 it might seem that we have solved the 241 00:12:02,220 --> 00:11:59,860 problem of how to do the SETI experiment 242 00:12:04,650 --> 00:12:02,230 look for artificial signals at radio 243 00:12:08,189 --> 00:12:04,660 frequencies unfortunately it's not that 244 00:12:12,059 --> 00:12:08,199 simple consider a terrestrial FM radio 245 00:12:14,220 --> 00:12:12,069 dial on earth we recognize the channels 246 00:12:16,439 --> 00:12:14,230 of our favorite radio stations defined 247 00:12:18,689 --> 00:12:16,449 in mega birds and can tone from one to 248 00:12:21,329 --> 00:12:18,699 the other each station has an assigned 249 00:12:23,220 --> 00:12:21,339 place on the dial there it broadcasts a 250 00:12:25,199 --> 00:12:23,230 carrier wave that's always present you 251 00:12:26,910 --> 00:12:25,209 no matter the program content the 252 00:12:31,079 --> 00:12:26,920 stations are separated from each other 253 00:12:33,600 --> 00:12:31,089 so that they do not interfere on the 254 00:12:35,669 --> 00:12:33,610 cosmic radio dial we're also looking for 255 00:12:38,220 --> 00:12:35,679 signals artificially concentrated in 256 00:12:39,960 --> 00:12:38,230 frequency but we don't know what 257 00:12:43,619 --> 00:12:39,970 frequencies the extraterrestrials may be 258 00:12:46,139 --> 00:12:43,629 using on earth between 90 and 92 259 00:12:49,590 --> 00:12:46,149 megahertz there are just ten frequencies 260 00:12:52,710 --> 00:12:49,600 in use on the cosmic dial there are 20 261 00:12:55,750 --> 00:12:52,720 million potentially usable frequencies 262 00:12:57,960 --> 00:12:55,760 in space the entire electromagnetic 263 00:13:00,790 --> 00:12:57,970 spectrum could be used for communication 264 00:13:03,030 --> 00:13:00,800 but in practice some portions of the 265 00:13:06,790 --> 00:13:03,040 cosmic radio dial are harder to use 266 00:13:09,430 --> 00:13:06,800 lower frequencies that we use for FM and 267 00:13:11,560 --> 00:13:09,440 TV broadcasts are overwhelmed by 268 00:13:14,500 --> 00:13:11,570 interference from natural sources in our 269 00:13:16,720 --> 00:13:14,510 galaxy so we think it makes sense to 270 00:13:20,200 --> 00:13:16,730 listen in the microwave region between 271 00:13:22,060 --> 00:13:20,210 1,000 and 100,000 megahertz there is a 272 00:13:24,310 --> 00:13:22,070 preferred region in the electromagnetic 273 00:13:27,160 --> 00:13:24,320 spectrum we believe to minimize as the 274 00:13:29,050 --> 00:13:27,170 energy required to make contact and that 275 00:13:31,600 --> 00:13:29,060 is the microwave region and the reason 276 00:13:33,250 --> 00:13:31,610 for that is that the noise that would 277 00:13:36,550 --> 00:13:33,260 interfere with our transmissions or 278 00:13:39,100 --> 00:13:36,560 theirs is lowest there if you know lower 279 00:13:41,830 --> 00:13:39,110 in frequency the noise increases noises 280 00:13:43,540 --> 00:13:41,840 of the galaxy produces you go higher in 281 00:13:46,360 --> 00:13:43,550 frequency quantum effects come in and 282 00:13:49,330 --> 00:13:46,370 create noise and in this silent valley 283 00:13:50,650 --> 00:13:49,340 between those two walls communication 284 00:13:53,650 --> 00:13:50,660 can be accomplished with the least 285 00:13:55,450 --> 00:13:53,660 energy of any region of the spectrum but 286 00:13:57,760 --> 00:13:55,460 even if there are clues about frequency 287 00:14:00,160 --> 00:13:57,770 you still must choose where when and 288 00:14:01,780 --> 00:14:00,170 exactly how to listen it's really more 289 00:14:04,480 --> 00:14:01,790 like looking for a needle inside a 290 00:14:06,400 --> 00:14:04,490 haystack inside a haystack for 291 00:14:08,130 --> 00:14:06,410 simplicity SETI researchers compared 292 00:14:10,780 --> 00:14:08,140 their experiments using three parameters 293 00:14:13,120 --> 00:14:10,790 in addition to frequency you have to 294 00:14:15,840 --> 00:14:13,130 choose directions to survey the whole 295 00:14:18,160 --> 00:14:15,850 sky or to target individual stars and 296 00:14:20,560 --> 00:14:18,170 all experiments will have different 297 00:14:23,410 --> 00:14:20,570 sensitivities determined primarily by 298 00:14:27,220 --> 00:14:23,420 the size of the radio antenna and by how 299 00:14:29,080 --> 00:14:27,230 long they listen are there any further 300 00:14:31,270 --> 00:14:29,090 clues which can help limit places to 301 00:14:33,220 --> 00:14:31,280 look for the needle many study 302 00:14:35,680 --> 00:14:33,230 researchers think there may be at least 303 00:14:37,570 --> 00:14:35,690 in the frequency dimension since 304 00:14:39,370 --> 00:14:37,580 hydrogen is the most abundant element in 305 00:14:41,380 --> 00:14:39,380 the universe they argue that all 306 00:14:43,390 --> 00:14:41,390 intelligent species would think of 307 00:14:44,980 --> 00:14:43,400 transmitting their signals close to the 308 00:14:47,610 --> 00:14:44,990 frequency at which hydrogen atoms 309 00:14:50,290 --> 00:14:47,620 naturally emit radio waves 310 00:14:53,410 --> 00:14:50,300 1420 megahertz was the first so-called 311 00:14:56,110 --> 00:14:53,420 magic frequency to be tried it was at 312 00:15:00,250 --> 00:14:56,120 1420 megahertz that Frank trach searched 313 00:15:02,350 --> 00:15:00,260 in 1960 the first targeted search he 314 00:15:04,390 --> 00:15:02,360 looked at just two stars at this one 315 00:15:08,320 --> 00:15:04,400 frequency in a search of moderate 316 00:15:10,510 --> 00:15:08,330 sensitivity in 1973 Ohio State 317 00:15:13,810 --> 00:15:10,520 University with its unusual antenna 318 00:15:16,090 --> 00:15:13,820 began a continuing sky servic it listens 319 00:15:18,580 --> 00:15:16,100 not to single stars but to the sky 320 00:15:22,630 --> 00:15:18,590 passing overhead it covers 50 channels 321 00:15:25,150 --> 00:15:22,640 but is low in sensitivity searches over 322 00:15:27,130 --> 00:15:25,160 the last six years by myself and French 323 00:15:30,310 --> 00:15:27,140 radio astronomer Francois Bureau at mal 324 00:15:32,890 --> 00:15:30,320 say have looked at 350 stars in the 325 00:15:34,930 --> 00:15:32,900 latest targeted search there has been 326 00:15:36,760 --> 00:15:34,940 significant international interest in 327 00:15:39,400 --> 00:15:36,770 setting with searches mounted in the 328 00:15:41,290 --> 00:15:39,410 USSR Canada Holland Germany and 329 00:15:41,710 --> 00:15:41,300 Australia as well as those in the United 330 00:15:46,749 --> 00:15:41,720 States 331 00:15:49,269 --> 00:15:46,759 friends I'd not say by adapting existing 332 00:15:51,040 --> 00:15:49,279 radio astronomical equipment we've been 333 00:15:53,679 --> 00:15:51,050 able to listen to thousands of channels 334 00:15:55,929 --> 00:15:53,689 simultaneously we've achieved improved 335 00:16:00,970 --> 00:15:55,939 frequency coverage and a modest gain in 336 00:16:02,889 --> 00:16:00,980 sensitivity as computers advanced it 337 00:16:04,600 --> 00:16:02,899 became possible to construct detectors 338 00:16:07,449 --> 00:16:04,610 that were specially adapted to the needs 339 00:16:09,309 --> 00:16:07,459 of Seti one of the first researchers to 340 00:16:11,619 --> 00:16:09,319 take advantage of this capability was 341 00:16:13,929 --> 00:16:11,629 Paul harvest a professor of physics at 342 00:16:16,059 --> 00:16:13,939 Harvard University the key breakthrough 343 00:16:20,829 --> 00:16:16,069 was the ability to scan many channels 344 00:16:22,090 --> 00:16:20,839 and frequencies simultaneously the heart 345 00:16:25,119 --> 00:16:22,100 of the system is a so-called 346 00:16:27,579 --> 00:16:25,129 multi-channel spectrum analyzer or mcsa 347 00:16:29,259 --> 00:16:27,589 the one Horowitz uses in his latest 348 00:16:31,449 --> 00:16:29,269 system was designed in collaboration 349 00:16:33,879 --> 00:16:31,459 with ivan lins gotten colleagues at 350 00:16:37,210 --> 00:16:33,889 Stanford University as part of the R&D 351 00:16:39,340 --> 00:16:37,220 for NASA's plan city systems Horowitz 352 00:16:42,790 --> 00:16:39,350 puts this equipment to practical test in 353 00:16:45,939 --> 00:16:42,800 a Sky Survey known as meta the mega 354 00:16:48,369 --> 00:16:45,949 channel extraterrestrial asset Drake's 355 00:16:51,970 --> 00:16:48,379 experiment could scan only one frequency 356 00:16:53,230 --> 00:16:51,980 channel at a time meta can listen to 8.4 357 00:16:55,929 --> 00:16:53,240 million frequency channels 358 00:17:00,189 --> 00:16:55,939 simultaneously it can do in one second 359 00:17:02,530 --> 00:17:00,199 which took Drake five years meta funded 360 00:17:05,500 --> 00:17:02,540 by the Planetary Society is perhaps the 361 00:17:07,569 --> 00:17:05,510 ultimate magic frequency machine but if 362 00:17:09,069 --> 00:17:07,579 Horowitz has guessed wrong he may be 363 00:17:11,409 --> 00:17:09,079 looking in the right direction with 364 00:17:14,340 --> 00:17:11,419 excellent sensitivity but just the wrong 365 00:17:20,529 --> 00:17:17,139 no search to date has found any evidence 366 00:17:22,569 --> 00:17:20,539 of intelligent life but SETI researchers 367 00:17:26,980 --> 00:17:22,579 feel that their equipment has not been 368 00:17:28,870 --> 00:17:26,990 equal to the task NASA's goal is to 369 00:17:31,930 --> 00:17:28,880 extend these previous efforts into a 370 00:17:33,669 --> 00:17:31,940 truly comprehensive search successful 371 00:17:35,529 --> 00:17:33,679 tests of hardware and software in 372 00:17:38,169 --> 00:17:35,539 detecting signals like those coming back 373 00:17:40,600 --> 00:17:38,179 from pioneer are but the first steps in 374 00:17:42,700 --> 00:17:40,610 a planned 10-year project that will 375 00:17:45,759 --> 00:17:42,710 combine the most promising strategies 376 00:17:47,259 --> 00:17:45,769 from these earlier searches the NASA 377 00:17:49,000 --> 00:17:47,269 approach that we're that we're 378 00:17:51,759 --> 00:17:49,010 developing right now has two different 379 00:17:54,310 --> 00:17:51,769 approaches to the search and they're 380 00:17:55,990 --> 00:17:54,320 complementary one of them is called the 381 00:17:57,940 --> 00:17:56,000 sky survey and another is called the 382 00:18:00,129 --> 00:17:57,950 target search and the objective of the 383 00:18:02,259 --> 00:18:00,139 sky survey is to search the entire sky 384 00:18:04,480 --> 00:18:02,269 having making no guesses as to what are 385 00:18:06,730 --> 00:18:04,490 the best directions to carry out that 386 00:18:08,169 --> 00:18:06,740 search in a reasonable length of time we 387 00:18:11,110 --> 00:18:08,179 have to do it quickly which means we 388 00:18:12,580 --> 00:18:11,120 sacrifice sensitivity to signals we only 389 00:18:15,190 --> 00:18:12,590 detect may be the strongest of the 390 00:18:17,350 --> 00:18:15,200 signals it might be there to cover this 391 00:18:19,960 --> 00:18:17,360 guy quickly the radio telescopes will be 392 00:18:22,810 --> 00:18:19,970 driven very rapidly eventually scanning 393 00:18:24,909 --> 00:18:22,820 each patch of the sky 30 times but it is 394 00:18:27,159 --> 00:18:24,919 in frequency sampled rather than 395 00:18:30,610 --> 00:18:27,169 directions covered that NASA's project 396 00:18:33,310 --> 00:18:30,620 will dwarf all previous searches Drake's 397 00:18:35,409 --> 00:18:33,320 loan frequency is gossamer thin in 398 00:18:37,450 --> 00:18:35,419 comparison to the tens of billions of 399 00:18:40,750 --> 00:18:37,460 usable frequencies in the naturally 400 00:18:43,000 --> 00:18:40,760 quiet microwave window and even though 401 00:18:45,490 --> 00:18:43,010 the ohio state survey covers lots of 402 00:18:48,129 --> 00:18:45,500 directions and stars about sixty percent 403 00:18:51,519 --> 00:18:48,139 of the sky overall its frequency range 404 00:18:54,490 --> 00:18:51,529 is also limited mehta also scans the 405 00:18:56,500 --> 00:18:54,500 northern skies but all of its 8.4 406 00:18:59,080 --> 00:18:56,510 million channels cluster around a single 407 00:19:02,740 --> 00:18:59,090 magic frequency though it will be tuned 408 00:19:05,350 --> 00:19:02,750 to others in contrast on the frequency 409 00:19:07,269 --> 00:19:05,360 dimension NASA Sky Survey will cover the 410 00:19:10,159 --> 00:19:07,279 whole one to ten gigahertz window and 411 00:19:12,259 --> 00:19:10,169 the entire sky 412 00:19:15,109 --> 00:19:12,269 to achieve this comprehensive coverage 413 00:19:17,029 --> 00:19:15,119 of directions and stars NASA plans to 414 00:19:18,739 --> 00:19:17,039 use several telescopes around the world 415 00:19:21,499 --> 00:19:18,749 which are part of its spacecraft 416 00:19:23,659 --> 00:19:21,509 tracking system each of these telescopes 417 00:19:25,519 --> 00:19:23,669 can see two-thirds of the sky and NASA 418 00:19:27,859 --> 00:19:25,529 will move its sky survey system between 419 00:19:31,639 --> 00:19:27,869 them the complementary approach is to 420 00:19:33,229 --> 00:19:31,649 say let's concentrate on detecting with 421 00:19:35,299 --> 00:19:33,239 more sensitivity to be able to tech 422 00:19:37,399 --> 00:19:35,309 weaker signals and to do that we look 423 00:19:39,229 --> 00:19:37,409 and wonder in a few directions for 424 00:19:42,289 --> 00:19:39,239 longer periods of time that's called the 425 00:19:45,259 --> 00:19:42,299 targeted search and we pre select a set 426 00:19:47,299 --> 00:19:45,269 of stars that we know Apriori are more 427 00:19:49,039 --> 00:19:47,309 or less similar to our own Sun in age 428 00:19:51,859 --> 00:19:49,049 and size and look in those directions 429 00:19:54,739 --> 00:19:51,869 with more sensitivity and the ability to 430 00:19:56,659 --> 00:19:54,749 tech many more complex signals the 431 00:19:58,759 --> 00:19:56,669 targeted search will look repeatedly and 432 00:20:02,899 --> 00:19:58,769 at different frequencies at nearly 800 433 00:20:05,419 --> 00:20:02,909 year by stars like mal say NASA's 434 00:20:08,720 --> 00:20:05,429 targeted search may start around 1420 435 00:20:09,979 --> 00:20:08,730 megahertz that is 1.4 2 gigahertz but 436 00:20:13,930 --> 00:20:09,989 then it will expand to cover all 437 00:20:16,639 --> 00:20:13,940 frequencies between one and three goods 438 00:20:20,330 --> 00:20:16,649 like the Sky Survey the targeted search 439 00:20:22,519 --> 00:20:20,340 requires antennas around the world the 440 00:20:24,769 --> 00:20:22,529 giant radio telescope at Arecibo is the 441 00:20:27,320 --> 00:20:24,779 largest on the planet and because of its 442 00:20:29,090 --> 00:20:27,330 unique size and sensitivity NASA hopes 443 00:20:31,940 --> 00:20:29,100 to share time to search for the very 444 00:20:34,249 --> 00:20:31,950 faintest signals the large dish can't be 445 00:20:38,960 --> 00:20:34,259 moved so it can only see stars which 446 00:20:41,269 --> 00:20:38,970 rotate overhead each day the antennas at 447 00:20:43,669 --> 00:20:41,279 either Ohio State or null say could be 448 00:20:47,560 --> 00:20:43,679 used to observe about 300 stars outside 449 00:20:52,070 --> 00:20:50,060 more of the target stars can be seen 450 00:20:54,109 --> 00:20:52,080 from the southern hemisphere so about 451 00:20:56,389 --> 00:20:54,119 200 of them could be observed from the 452 00:20:58,460 --> 00:20:56,399 large NASA antenna at Canberra or 453 00:21:03,830 --> 00:20:58,470 perhaps the astronomical facility at 454 00:21:05,840 --> 00:21:03,840 parks in Australia the last 50 or so 455 00:21:08,539 --> 00:21:05,850 stars must be searched from a telescope 456 00:21:11,180 --> 00:21:08,549 in the northern latitudes perhaps rather 457 00:21:15,519 --> 00:21:11,190 appropriately and green deck where Frank 458 00:21:20,269 --> 00:21:18,379 with this unparalleled combination of 459 00:21:22,940 --> 00:21:20,279 advanced hardware and sophisticated 460 00:21:27,379 --> 00:21:22,950 software NASA's project will have the 461 00:21:31,459 --> 00:21:29,509 the targeted search will look for faint 462 00:21:33,169 --> 00:21:31,469 signals from what according to the 463 00:21:35,149 --> 00:21:33,179 current understanding of cosmic 464 00:21:37,459 --> 00:21:35,159 evolution seem to be the most 465 00:21:40,879 --> 00:21:37,469 interesting sights and we'll look at 466 00:21:42,649 --> 00:21:40,889 billions of frequencies the sky survey 467 00:21:44,629 --> 00:21:42,659 will color an even wider range of 468 00:21:46,699 --> 00:21:44,639 frequencies yet with sufficient 469 00:21:50,239 --> 00:21:46,709 sensitivity to detect a very strong 470 00:21:52,099 --> 00:21:50,249 signal from clear across the galaxy in 471 00:21:53,959 --> 00:21:52,109 addition NASA system will have an 472 00:21:55,759 --> 00:21:53,969 unprecedented ability to look for 473 00:21:58,999 --> 00:21:55,769 different types of signals that vary 474 00:22:01,249 --> 00:21:59,009 over time not just a continuous carrier 475 00:22:04,789 --> 00:22:01,259 wave like that of pioneer 10 or Earth's 476 00:22:06,979 --> 00:22:04,799 radio broadcasts for the first time we 477 00:22:08,899 --> 00:22:06,989 will be able to detect regular pulses 478 00:22:10,699 --> 00:22:08,909 that some researchers say will save 479 00:22:12,769 --> 00:22:10,709 energy and so be the choice of the 480 00:22:15,469 --> 00:22:12,779 transmitting civilization the 481 00:22:18,079 --> 00:22:15,479 interesting thing about the citysearch 482 00:22:19,789 --> 00:22:18,089 is that although we claim that we're 483 00:22:23,539 --> 00:22:19,799 looking for extraterrestrial 484 00:22:27,049 --> 00:22:23,549 intelligence we can't actually define 485 00:22:29,299 --> 00:22:27,059 what an intelligent signal is and so a 486 00:22:32,899 --> 00:22:29,309 starting point is to say we look for a 487 00:22:35,749 --> 00:22:32,909 signal which nature will not produce by 488 00:22:37,669 --> 00:22:35,759 any mechanism that we understand where 489 00:22:39,649 --> 00:22:37,679 it becomes kent colors helped NASA 490 00:22:41,479 --> 00:22:39,659 design the smart computer algorithms 491 00:22:43,729 --> 00:22:41,489 needed to locate weak signals and in 492 00:22:45,199 --> 00:22:43,739 many channels of noise figure but there 493 00:22:48,199 --> 00:22:45,209 will be no human staring at 494 00:22:50,089 --> 00:22:48,209 sophisticated graphics display no human 495 00:22:52,159 --> 00:22:50,099 is any more cited than Kent when it 496 00:22:55,279 --> 00:22:52,169 comes to recognizing an extraterrestrial 497 00:22:58,789 --> 00:22:55,289 signal so the eye is not a good detector 498 00:23:00,739 --> 00:22:58,799 first of all in sensitivity a thing that 499 00:23:02,029 --> 00:23:00,749 you could look at virtually forever and 500 00:23:04,190 --> 00:23:02,039 you would never know whether you were 501 00:23:07,879 --> 00:23:04,200 seeing random noise or whether you were 502 00:23:11,239 --> 00:23:07,889 seeing a real signal the computer can 503 00:23:15,349 --> 00:23:11,249 find signals that are 10 times weaker 504 00:23:17,119 --> 00:23:15,359 than that the amount of data processed 505 00:23:19,159 --> 00:23:17,129 per second is the equivalent of the 506 00:23:21,289 --> 00:23:19,169 entire Encyclopedia Britannica per 507 00:23:24,919 --> 00:23:21,299 second of course that's filled with 508 00:23:27,379 --> 00:23:24,929 random letters if that's analogous to 509 00:23:30,739 --> 00:23:27,389 noise and what you have to do is find 510 00:23:32,779 --> 00:23:30,749 that one pattern that says hi there in 511 00:23:34,699 --> 00:23:32,789 all of those random letters that come in 512 00:23:36,019 --> 00:23:34,709 every second and then decide whether 513 00:23:37,240 --> 00:23:36,029 that pattern could have happened at 514 00:23:39,400 --> 00:23:37,250 random because 515 00:23:42,220 --> 00:23:39,410 your statistics of your process or 516 00:23:45,310 --> 00:23:42,230 whether in fact that's the real thing 517 00:23:47,140 --> 00:23:45,320 and a human being even if he could 518 00:23:50,430 --> 00:23:47,150 perform the task as effectively as a 519 00:23:52,420 --> 00:23:50,440 computer couldn't do it for very long 520 00:23:54,040 --> 00:23:52,430 removing humans from the signal 521 00:23:56,200 --> 00:23:54,050 detection process requires a very 522 00:23:57,910 --> 00:23:56,210 special hardware which is what Ivan 523 00:24:00,210 --> 00:23:57,920 Linscott and his colleagues at Stanford 524 00:24:03,250 --> 00:24:00,220 University have been designing and 525 00:24:05,970 --> 00:24:03,260 that's like having 10 million ears each 526 00:24:08,200 --> 00:24:05,980 one listening to a particular tone and 527 00:24:10,210 --> 00:24:08,210 where all of those are listening 528 00:24:13,390 --> 00:24:10,220 simultaneously and so what we're doing 529 00:24:15,910 --> 00:24:13,400 now is taking the technology that exists 530 00:24:18,340 --> 00:24:15,920 in this prototype form and casting it in 531 00:24:21,040 --> 00:24:18,350 sand we're building silicon versions of 532 00:24:23,770 --> 00:24:21,050 our processors that that together with 533 00:24:27,010 --> 00:24:23,780 the way we know how to use them will 534 00:24:29,140 --> 00:24:27,020 convince both the scale and increase the 535 00:24:35,500 --> 00:24:29,150 performance the process of 536 00:24:38,080 --> 00:24:35,510 miniaturization is already underway 680 537 00:24:40,330 --> 00:24:38,090 of the older large boards will soon be 538 00:24:42,610 --> 00:24:40,340 replaced by just 24 smaller boards 539 00:24:44,740 --> 00:24:42,620 filled with new chips that are cheaper 540 00:24:47,230 --> 00:24:44,750 smarter and faster and can be more 541 00:24:50,290 --> 00:24:47,240 easily transported around the world no 542 00:24:52,540 --> 00:24:50,300 longer will require you to step in small 543 00:24:56,410 --> 00:24:52,550 chunks across the frequency band you can 544 00:24:58,510 --> 00:24:56,420 make a giant stride and and spend lots 545 00:25:01,520 --> 00:24:58,520 of time on particular sources or or 546 00:25:02,690 --> 00:25:01,530 sweep broad swath of the sky 547 00:25:05,540 --> 00:25:02,700 and I think there's where the 548 00:25:07,700 --> 00:25:05,550 opportunity lies because it's a 549 00:25:11,330 --> 00:25:07,710 prospectors art you know and you just 550 00:25:13,520 --> 00:25:11,340 have to look and take your best bet in 551 00:25:15,350 --> 00:25:13,530 normal operations the NASA systems will 552 00:25:17,270 --> 00:25:15,360 rely very heavily on silicon 553 00:25:20,240 --> 00:25:17,280 intelligence with limited human 554 00:25:22,520 --> 00:25:20,250 involvement the computers will have to 555 00:25:24,200 --> 00:25:22,530 have sufficient online intelligence to 556 00:25:26,870 --> 00:25:24,210 analyze the vast amounts of data 557 00:25:28,970 --> 00:25:26,880 arriving every second and weed out the 558 00:25:32,690 --> 00:25:28,980 inevitable false alarms before involving 559 00:25:35,120 --> 00:25:32,700 humans for the operational sky survey 560 00:25:37,130 --> 00:25:35,130 the sky will automatically be divided 561 00:25:40,520 --> 00:25:37,140 into blocks which will be searched in 562 00:25:42,830 --> 00:25:40,530 turn NASA expects many suspicious 563 00:25:45,260 --> 00:25:42,840 signals during each scan but they won't 564 00:25:47,390 --> 00:25:45,270 be from extraterrestrials these events 565 00:25:50,540 --> 00:25:47,400 will be compared to the online database 566 00:25:53,300 --> 00:25:50,550 of radio frequency interference RFI to 567 00:25:55,460 --> 00:25:53,310 identify man-made signals most of the 568 00:25:58,340 --> 00:25:55,470 signals will be explained away until 569 00:26:02,030 --> 00:25:58,350 someday maybe there might come something 570 00:26:04,070 --> 00:26:02,040 more significant the characteristics of 571 00:26:06,590 --> 00:26:04,080 the long hoped for signal will show some 572 00:26:12,200 --> 00:26:06,600 clear sign of intelligence and the 573 00:26:14,030 --> 00:26:12,210 computer will have made content then it 574 00:26:15,830 --> 00:26:14,040 will call humans to come look and we 575 00:26:20,150 --> 00:26:15,840 will know for sure about life elsewhere 576 00:26:22,400 --> 00:26:20,160 in space but before that increasing RFI 577 00:26:25,610 --> 00:26:22,410 poses the greatest obstacle to success 578 00:26:26,720 --> 00:26:25,620 think of the haystack principle we're 579 00:26:29,630 --> 00:26:26,730 looking for the needle in the haystack 580 00:26:32,150 --> 00:26:29,640 as a gold needle same color as the hay 581 00:26:33,800 --> 00:26:32,160 in the haystack but some Joker has 582 00:26:36,290 --> 00:26:33,810 thrown an awful lot of bras needles in 583 00:26:38,390 --> 00:26:36,300 the haystack too so not only do we have 584 00:26:39,890 --> 00:26:38,400 to pick up every little straw and sort 585 00:26:42,050 --> 00:26:39,900 of crinkle it our fingers to see if it 586 00:26:43,760 --> 00:26:42,060 sell it or not but we also have to test 587 00:26:46,640 --> 00:26:43,770 every solid one because it might be a 588 00:26:48,440 --> 00:26:46,650 bronze one since the first SETI 589 00:26:50,960 --> 00:26:48,450 experiments we have filled Earth's skies 590 00:26:53,810 --> 00:26:50,970 with all manner of satellites and we use 591 00:26:55,820 --> 00:26:53,820 them continuously for this reason said 592 00:26:57,920 --> 00:26:55,830 he must get started soon or it will 593 00:27:00,400 --> 00:26:57,930 become more and more difficult to sort 594 00:27:05,049 --> 00:27:00,410 out man-made signals from possible 595 00:27:09,380 --> 00:27:07,400 from the early theories of Philip 596 00:27:11,630 --> 00:27:09,390 morrison and the Ozma experiment of 597 00:27:14,870 --> 00:27:11,640 Frank Drake past searches have 598 00:27:17,600 --> 00:27:14,880 tantalized as much as resolved now in 599 00:27:20,480 --> 00:27:17,610 the proposed NASA search technology and 600 00:27:22,190 --> 00:27:20,490 task are beginning to converge millions 601 00:27:24,230 --> 00:27:22,200 of times we've in fact even billions of 602 00:27:26,630 --> 00:27:24,240 times more comprehensive than the sum of 603 00:27:28,190 --> 00:27:26,640 all previous searches but fall short by 604 00:27:31,039 --> 00:27:28,200 about a million fold from what could be 605 00:27:33,260 --> 00:27:31,049 done so we're kind of nicely positioned 606 00:27:35,690 --> 00:27:33,270 in the middle and if we succeed we will 607 00:27:37,490 --> 00:27:35,700 succeed with the cheap play searching 608 00:27:39,980 --> 00:27:37,500 the cosmic haystack with the full NASA 609 00:27:43,180 --> 00:27:39,990 system would cost just a few pennies per 610 00:27:46,460 --> 00:27:43,190 american per year is it worth that price 611 00:27:48,650 --> 00:27:46,470 when I take my paycheck home I certainly 612 00:27:51,110 --> 00:27:48,660 pay my house bill and my medical bills 613 00:27:53,419 --> 00:27:51,120 and I insurance premiums first and that 614 00:27:56,270 --> 00:27:53,429 takes up most of my income but I always 615 00:27:58,430 --> 00:27:56,280 save a little bit to buy a book or go to 616 00:28:00,500 --> 00:27:58,440 a good movie or go to the Art Museum or 617 00:28:02,870 --> 00:28:00,510 go to a football game and I think it's 618 00:28:05,750 --> 00:28:02,880 that kind of activity that's necessary 619 00:28:07,250 --> 00:28:05,760 for us as human beings to keep us human 620 00:28:09,640 --> 00:28:07,260 I mean that's what that's what keeps our 621 00:28:11,690 --> 00:28:09,650 curiosity stimulated our our our 622 00:28:14,570 --> 00:28:11,700 intellect moving and I think we 623 00:28:16,810 --> 00:28:14,580 collectively as a human race also need 624 00:28:19,610 --> 00:28:16,820 to invest some of our resources into 625 00:28:22,130 --> 00:28:19,620 exploration into trying to understand 626 00:28:25,669 --> 00:28:22,140 nature as it is around us nature as it 627 00:28:27,650 --> 00:28:25,679 is out there and the cosmos trying to 628 00:28:29,900 --> 00:28:27,660 learn who we are and what we're like I 629 00:28:31,190 --> 00:28:29,910 think we always need to climb that extra 630 00:28:33,830 --> 00:28:31,200 mountain somehow I think that's very 631 00:28:35,120 --> 00:28:33,840 important to us collectively I think 632 00:28:38,120 --> 00:28:35,130 even if there's a plausible argument for 633 00:28:39,980 --> 00:28:38,130 a few we got to keep looking I even go 634 00:28:41,450 --> 00:28:39,990 further than that if there's a plausible 635 00:28:43,610 --> 00:28:41,460 argument that there isn't anybody out 636 00:28:45,470 --> 00:28:43,620 there bearing in mind that we can be 637 00:28:48,380 --> 00:28:45,480 wrong we ought to keep looking because 638 00:28:51,260 --> 00:28:48,390 the question is of the most supreme 639 00:28:54,100 --> 00:28:51,270 importance it calibrates our place in 640 00:28:57,740 --> 00:28:54,110 the universe it tells us who we are and 641 00:29:00,409 --> 00:28:57,750 so it is worthwhile trying to find other 642 00:29:02,930 --> 00:29:00,419 civilizations I would say no matter what 643 00:29:05,000 --> 00:29:02,940 we've hardly searched all the various 644 00:29:06,860 --> 00:29:05,010 frequencies the forms of signal the 645 00:29:10,010 --> 00:29:06,870 places in the sky from which signals 646 00:29:12,169 --> 00:29:10,020 might come and so the fact that we so 647 00:29:13,850 --> 00:29:12,179 far have no evidence of extraterrestrial 648 00:29:15,470 --> 00:29:13,860 life is not at all discouraging we 649 00:29:18,320 --> 00:29:15,480 shouldn't have found it yet 650 00:29:20,570 --> 00:29:18,330 we have hardly begun but i think this 651 00:29:22,850 --> 00:29:20,580 enterprise can best be understood as a 652 00:29:25,100 --> 00:29:22,860 kind of exercise in the archaeology of 653 00:29:28,430 --> 00:29:25,110 the future we're well aware of the 654 00:29:31,760 --> 00:29:28,440 archaeology of the past we find a site a 655 00:29:33,740 --> 00:29:31,770 tumulus or a ruin and we take a spade 656 00:29:36,590 --> 00:29:33,750 and we dig into the ground and if you're 657 00:29:39,350 --> 00:29:36,600 lucky you discover or of the kaldi's or 658 00:29:41,210 --> 00:29:39,360 something marvelous now we ever thought 659 00:29:43,490 --> 00:29:41,220 that we could examine the same thing in 660 00:29:46,040 --> 00:29:43,500 reverse time but in fact in a way we can 661 00:29:48,230 --> 00:29:46,050 we know that it's possible that somebody 662 00:29:52,010 --> 00:29:48,240 who wants to do it will bring us in of 663 00:29:53,660 --> 00:29:52,020 course it is their past but our future 664 00:29:55,460 --> 00:29:53,670 which we are investigating to some 665 00:29:56,690 --> 00:29:55,470 degree even though they're made of 666 00:29:58,640 --> 00:29:56,700 different chemistry even though they've 667 00:30:02,180 --> 00:29:58,650 never seen our star even though they 668 00:30:04,340 --> 00:30:02,190 have nothing biological in common with 669 00:30:05,330 --> 00:30:04,350 us they have if they have got radio 670 00:30:07,280 --> 00:30:05,340 astronomy if they have the Conn 671 00:30:09,080 --> 00:30:07,290 technology were imagining have very much 672 00:30:10,760 --> 00:30:09,090 income with us the manufacturer of a 673 00:30:13,430 --> 00:30:10,770 culture the development of a culture 674 00:30:16,040 --> 00:30:13,440 which is unmatched among in all the ten 675 00:30:17,870 --> 00:30:16,050 billion species or more that have come 676 00:30:19,790 --> 00:30:17,880 to the face of the earth so that's the 677 00:30:22,220 --> 00:30:19,800 story and maybe the spag will turn up 678 00:30:23,960 --> 00:30:22,230 luckily a good site one day we hope it 679 00:30:25,970 --> 00:30:23,970 will it's just a question being patient 680 00:30:29,090 --> 00:30:25,980 when you got the Spade and you know the