1 00:00:01,920 --> 00:00:06,360 Speaker 1: Welcome to brain Stuff production of I Heart Radio. Hey 2 00:00:06,400 --> 00:00:09,080 Speaker 1: brain Stuff, I'm Lauren Vogelbaum, and today's episode is a 3 00:00:09,119 --> 00:00:12,720 Speaker 1: classic from our previous host, Christian Sager. This one was 4 00:00:12,760 --> 00:00:16,520 Speaker 1: written and recorded right after the Voyager one spacecraft entered 5 00:00:16,560 --> 00:00:19,959 Speaker 1: interstellar space, so the team wanted to talk about what 6 00:00:20,040 --> 00:00:22,760 Speaker 1: this amazing craft has done for us so far and 7 00:00:22,800 --> 00:00:27,960 Speaker 1: what it might still do in the future. Hey brain Stuff, 8 00:00:28,000 --> 00:00:32,280 Speaker 1: it's Christian Sager. On September five, nine seventy seven, NASA's 9 00:00:32,320 --> 00:00:37,320 Speaker 1: historic Voyager one mission launched, joining its identical robotic twin, 10 00:00:37,680 --> 00:00:40,920 Speaker 1: Voyager two, on what would turn out to be a 11 00:00:41,080 --> 00:00:46,120 Speaker 1: forty year odyssey through the Solar System and into interstellar space. 12 00:00:46,600 --> 00:00:49,519 Speaker 1: Voyager two had launched more than two weeks earlier, on 13 00:00:49,600 --> 00:00:56,200 Speaker 1: August nine, and both spacecraft completed the dazzling grand tour 14 00:00:56,360 --> 00:01:00,400 Speaker 1: of the outer Solar systems planets. Voyager one has now 15 00:01:00,600 --> 00:01:05,600 Speaker 1: left our Son's heliosphere, becoming a bona fide interstellar probe 16 00:01:05,840 --> 00:01:09,840 Speaker 1: and the most distant human made vehicle, and Voyager two 17 00:01:10,120 --> 00:01:13,160 Speaker 1: is about to flirt with the outermost boundary of the 18 00:01:13,160 --> 00:01:18,480 Speaker 1: heliosphere the Helio Pause. But exploring interstellar space wasn't a 19 00:01:18,520 --> 00:01:22,319 Speaker 1: mission objective back in nineteen seventy seven. Back then, the 20 00:01:22,400 --> 00:01:26,320 Speaker 1: Twin Probes aim was to reveal the rich diversity and 21 00:01:26,440 --> 00:01:30,640 Speaker 1: mystery of the outer Solar System's planets. For Ed Stone, 22 00:01:30,680 --> 00:01:34,080 Speaker 1: who has been project scientist for the Voyagers since nineteen 23 00:01:34,160 --> 00:01:38,360 Speaker 1: seventy two, his favorite memory was the jaw dropping discovery 24 00:01:38,400 --> 00:01:42,479 Speaker 1: of volcanoes on Jupiter's moon Io in nineteen seventy nine. 25 00:01:42,920 --> 00:01:46,080 Speaker 1: He said the eruptions on Io were the first direct 26 00:01:46,160 --> 00:01:50,120 Speaker 1: evidence of active volcanoes elsewhere in the Solar System, and 27 00:01:50,160 --> 00:01:53,920 Speaker 1: he wasn't wrong. Both Voyager one and two changed our 28 00:01:54,000 --> 00:01:58,240 Speaker 1: perspective of our Solar System, revealing never before seeing details 29 00:01:58,240 --> 00:02:03,640 Speaker 1: in planetary atmospheres and revealing new discoveries about interplanetary space. 30 00:02:04,200 --> 00:02:07,400 Speaker 1: New insights to Saturn's beautiful rings were gleaned, and a 31 00:02:07,560 --> 00:02:13,200 Speaker 1: huge diversity of moons swarming around the gas giants was revealed. 32 00:02:13,720 --> 00:02:17,840 Speaker 1: There are few more visceral science impacts on society than 33 00:02:17,880 --> 00:02:21,960 Speaker 1: when in n Voyager one was commanded to turn around 34 00:02:22,280 --> 00:02:26,360 Speaker 1: and capture an image of Earth from nearly four billion 35 00:02:26,480 --> 00:02:31,280 Speaker 1: miles or six point four billion kilometers distant. This was 36 00:02:31,320 --> 00:02:36,360 Speaker 1: at the request of Superstar astronomer and science communicator Carl Sagan. 37 00:02:36,760 --> 00:02:40,080 Speaker 1: In an interview with space dot com, Stone estimated that 38 00:02:40,160 --> 00:02:44,720 Speaker 1: both spacecraft only have about ten years supply of power 39 00:02:44,919 --> 00:02:49,440 Speaker 1: left before the plutonium heat output dwindles to levels that 40 00:02:49,480 --> 00:02:55,160 Speaker 1: won't sustain any spacecraft instrumentation or critical subsystems. Though the 41 00:02:55,240 --> 00:02:59,200 Speaker 1: Voyagers will eventually die, they continue to take data, and 42 00:02:59,280 --> 00:03:03,040 Speaker 1: Voyager one is taking measurements of a very alien region, 43 00:03:03,360 --> 00:03:08,480 Speaker 1: the interstellar medium. On August two thousand and twelve, NASA 44 00:03:08,520 --> 00:03:13,160 Speaker 1: confirmed that Voyager one had officially left the heliosphere, speeding 45 00:03:13,480 --> 00:03:17,240 Speaker 1: into interstellar space. Voyager two is traveling in a different 46 00:03:17,280 --> 00:03:21,840 Speaker 1: direction and has an encountered interstellar space. Yet the mysterious 47 00:03:21,880 --> 00:03:25,200 Speaker 1: outermost regions of the Solar System have now been probed, 48 00:03:25,240 --> 00:03:28,200 Speaker 1: and Voyager one was able to take measurements of the 49 00:03:28,240 --> 00:03:32,680 Speaker 1: magnetic field and particle energies, important measurements that have allowed 50 00:03:32,720 --> 00:03:36,840 Speaker 1: scientists a very privileged view of how our Son's magnetic 51 00:03:36,880 --> 00:03:40,840 Speaker 1: field and solar wind particles interact with the space between 52 00:03:40,920 --> 00:03:46,400 Speaker 1: the stars. So, after four decades of exploration, two spacecraft 53 00:03:46,440 --> 00:03:51,040 Speaker 1: built from nineteen seventies technology are still exploring and a 54 00:03:51,200 --> 00:03:55,080 Speaker 1: new generation of scientists are using them to carry out 55 00:03:55,120 --> 00:03:58,560 Speaker 1: cutting edge research in a region of space that no 56 00:03:58,880 --> 00:04:03,400 Speaker 1: other robot that we know of has ever experienced. Even 57 00:04:03,440 --> 00:04:07,080 Speaker 1: after their power supplies dwindle and the Voyagers lose communication 58 00:04:07,120 --> 00:04:11,880 Speaker 1: with Earth, they will be silent interstellar emissaries for humanity, 59 00:04:12,320 --> 00:04:16,279 Speaker 1: carrying the Golden Records as shrines of the civilization that 60 00:04:16,480 --> 00:04:22,000 Speaker 1: built these incredible machines should an extraterrestrial intelligence stumble upon 61 00:04:22,160 --> 00:04:31,159 Speaker 1: them and the eons to come. Since this episode aired, 62 00:04:31,279 --> 00:04:34,839 Speaker 1: Voyager two has also entered interstellar space, and both craft 63 00:04:34,960 --> 00:04:39,000 Speaker 1: have several systems still operational. Today's episode was written by 64 00:04:39,040 --> 00:04:41,760 Speaker 1: Ian O'Neill and produced by Dylan Fagan and Tyler Clang. 65 00:04:42,160 --> 00:04:44,360 Speaker 1: For more on this and lots of other far reaching topics, 66 00:04:44,440 --> 00:04:47,320 Speaker 1: visit how stuffworks dot com. Brain Stuff is a production 67 00:04:47,320 --> 00:04:49,720 Speaker 1: of I Heart Radio. For more podcasts in my heart Radio, 68 00:04:49,839 --> 00:04:52,520 Speaker 1: visit the iHeart Radio app, Apple Podcasts, or wherever you 69 00:04:52,560 --> 00:04:53,760 Speaker 1: listen to your favorite shows.