1 00:00:01,920 --> 00:00:07,000 Speaker 1: Welcome to brain Stuff production of iHeart Radio. Hey brain 2 00:00:07,080 --> 00:00:12,240 Speaker 1: Stuff learned Volga bam here. In November one, NASA's double 3 00:00:12,360 --> 00:00:17,840 Speaker 1: Asteroid Redirection test robotic spacecraft, called DART for short, took 4 00:00:17,840 --> 00:00:21,000 Speaker 1: off into space on a SpaceX Falcon nine rocket on 5 00:00:21,040 --> 00:00:24,440 Speaker 1: a mission to intercept and change the orbit of an asteroid. 6 00:00:25,920 --> 00:00:30,440 Speaker 1: Sometime in September or October, when DART is about seven 7 00:00:30,440 --> 00:00:34,720 Speaker 1: million miles or eleven million kilometers from our planet, this spacecraft, 8 00:00:34,840 --> 00:00:38,680 Speaker 1: weighing twelve thousand pounds or five fifty kilos and costing 9 00:00:38,720 --> 00:00:43,600 Speaker 1: three five million dollars, will reach its target, Dimorphous, a 10 00:00:43,720 --> 00:00:47,720 Speaker 1: small asteroid that orbits a second larger piece of space rock, Didimus, 11 00:00:48,120 --> 00:00:51,200 Speaker 1: as the pair travels in an elliptical orbit around the Sun. 12 00:00:51,920 --> 00:00:54,600 Speaker 1: While Dimorphous is not on course to hit the Earth, 13 00:00:54,840 --> 00:00:58,360 Speaker 1: it does provide a nice safe target for testing technology 14 00:00:58,520 --> 00:01:00,840 Speaker 1: that might someday helped he to the Earth from a 15 00:01:00,920 --> 00:01:04,240 Speaker 1: catastrophic collision with a killer asteroid, as such as the 16 00:01:04,240 --> 00:01:07,600 Speaker 1: one that wiped out the dinosaurs and plant and animal 17 00:01:07,640 --> 00:01:12,200 Speaker 1: life some sixty six million years ago. When it reaches 18 00:01:12,240 --> 00:01:15,240 Speaker 1: dim Morphous, DART will slam into the space rock at 19 00:01:15,280 --> 00:01:17,920 Speaker 1: a speed of about six point six kilometers or four 20 00:01:17,959 --> 00:01:21,640 Speaker 1: point one miles per second, hopefully giving the asteroid enough 21 00:01:21,680 --> 00:01:24,240 Speaker 1: of a jolt to alter its orbit around its partner 22 00:01:24,800 --> 00:01:28,320 Speaker 1: just slightly, but enough that the alteration might be observed 23 00:01:28,360 --> 00:01:33,280 Speaker 1: by telescopes on Earth. For the article of this episode 24 00:01:33,319 --> 00:01:35,720 Speaker 1: is based on How Stuff Works. Spoke by email with 25 00:01:35,800 --> 00:01:40,720 Speaker 1: Linley Johnson, NASA's first ever planetary Defense officer, he said 26 00:01:41,319 --> 00:01:43,840 Speaker 1: DART is a test of the effectiveness of the kinetic 27 00:01:43,959 --> 00:01:47,880 Speaker 1: impact or technique for altering an asteroid's orbital path, and 28 00:01:48,120 --> 00:01:51,360 Speaker 1: of the spacecraft technology used to deliver a kinetic impact 29 00:01:51,440 --> 00:01:55,440 Speaker 1: or to the target asteroid. Crashing a spacecraft into an 30 00:01:55,440 --> 00:01:59,480 Speaker 1: asteroid might sound easy, but it's not how stuff works. 31 00:01:59,520 --> 00:02:03,440 Speaker 1: Also with Andy Rivkin, the DART investigation co lead from 32 00:02:03,480 --> 00:02:06,800 Speaker 1: the Johns Hopkins Applied Physics Laboratory, which is leading the 33 00:02:06,840 --> 00:02:11,240 Speaker 1: project for NASA, he said, Dimorphus is the smallest object 34 00:02:11,320 --> 00:02:13,919 Speaker 1: that has ever been a mission target, and we're coming 35 00:02:13,960 --> 00:02:16,440 Speaker 1: in very fast with a need to impact on the 36 00:02:16,480 --> 00:02:20,600 Speaker 1: first try, without knowing fundamental things like dimorphous is shape 37 00:02:20,680 --> 00:02:24,760 Speaker 1: or exact size. It's about three thousand, six hundred feet 38 00:02:24,800 --> 00:02:28,120 Speaker 1: that's one thous from the center of Dinomus to the 39 00:02:28,200 --> 00:02:32,120 Speaker 1: center of dimorphous and it's probably less than two thousand 40 00:02:32,160 --> 00:02:34,840 Speaker 1: feet or six hundred meters from the surface of one 41 00:02:34,960 --> 00:02:37,600 Speaker 1: to the surface of the other. We don't want to 42 00:02:37,680 --> 00:02:42,400 Speaker 1: miss and we don't want to hit Didymus. Furthermore, the 43 00:02:42,480 --> 00:02:45,600 Speaker 1: spacecraft has to overtake that target at such a high 44 00:02:45,680 --> 00:02:49,480 Speaker 1: speed that there's very little margin for error the blink 45 00:02:49,520 --> 00:02:52,560 Speaker 1: of an eye, according to the DART team. To achieve 46 00:02:52,600 --> 00:02:56,880 Speaker 1: the necessary precision, the spacecraft will be guided by smart nav, 47 00:02:57,280 --> 00:03:01,200 Speaker 1: a totally automated navigation system that require there's no human input. 48 00:03:02,320 --> 00:03:05,280 Speaker 1: The spacecraft will also utilize an imaging instrument called the 49 00:03:05,320 --> 00:03:09,240 Speaker 1: Denimus Reconnaissance and Asteroid camera for op NAV a k A. 50 00:03:09,480 --> 00:03:12,800 Speaker 1: Draco to see where it's going, but it'll only be 51 00:03:12,880 --> 00:03:15,959 Speaker 1: able to see its target in the last hour before impact. 52 00:03:17,720 --> 00:03:20,480 Speaker 1: How Stuff works also spoke by email with Dark program 53 00:03:20,560 --> 00:03:24,440 Speaker 1: scientist Tom Statler. He said, if we ever need to 54 00:03:24,480 --> 00:03:27,720 Speaker 1: carry out a kinetic impact to prevent a natural disaster, 55 00:03:28,240 --> 00:03:30,680 Speaker 1: we might need to do so quite far from Earth, 56 00:03:30,919 --> 00:03:34,880 Speaker 1: which would make autonomous control by the spacecraft absolutely essential. 57 00:03:35,440 --> 00:03:38,400 Speaker 1: That's why we want to demonstrate and validate this technology 58 00:03:38,440 --> 00:03:42,200 Speaker 1: with DART. The scientists don't really know what will happen 59 00:03:42,280 --> 00:03:45,480 Speaker 1: when Dart hits the asteroid. Though. The thing is is 60 00:03:45,520 --> 00:03:47,560 Speaker 1: that although they have a pretty good idea of what 61 00:03:47,640 --> 00:03:50,920 Speaker 1: dimorphous is made up of, they're not sure how solidly 62 00:03:51,040 --> 00:03:54,480 Speaker 1: that material is sewn together. If it's just a loose 63 00:03:54,520 --> 00:03:58,240 Speaker 1: collection of rebel held together by gravity, that will impact 64 00:03:58,440 --> 00:04:01,680 Speaker 1: the impact of how much material is broken off into 65 00:04:01,680 --> 00:04:06,240 Speaker 1: space and how much Dimorphous budgets in its orbit. A 66 00:04:06,400 --> 00:04:09,320 Speaker 1: dart is an early step in protecting human life from 67 00:04:09,400 --> 00:04:12,120 Speaker 1: being wiped out by a space rock, but it also 68 00:04:12,240 --> 00:04:16,320 Speaker 1: changes humanity's relationship to the cosmos. Up to this point, 69 00:04:16,480 --> 00:04:19,520 Speaker 1: space has been something that we watch from afar and 70 00:04:19,560 --> 00:04:23,560 Speaker 1: occasionally send brave souls to visit for brief periods. But 71 00:04:23,800 --> 00:04:27,000 Speaker 1: now it's going to become something that humans can tinker with, 72 00:04:27,520 --> 00:04:30,720 Speaker 1: just as we've altered our own planet. Has stuff works 73 00:04:30,760 --> 00:04:33,720 Speaker 1: also spoke by an email with Martin Elvis, an astrophysicist 74 00:04:33,760 --> 00:04:37,080 Speaker 1: at the Center for Astrophysics, Harvard and Smithsonian and author 75 00:04:37,160 --> 00:04:41,920 Speaker 1: of the book Asteroids, How Love, fear Ingreed will determine 76 00:04:41,920 --> 00:04:46,279 Speaker 1: our future in space. He said, perhaps the biggest point 77 00:04:46,480 --> 00:04:49,880 Speaker 1: is that Dart will be humanity's first attempt to deliberately 78 00:04:50,040 --> 00:04:53,279 Speaker 1: change the orbit of a solar system body. The amount 79 00:04:53,320 --> 00:04:56,560 Speaker 1: we will change the orbital speed of dimorphous will only 80 00:04:56,640 --> 00:05:00,640 Speaker 1: be by blessed than a snail's pace, literally four point 81 00:05:00,680 --> 00:05:04,320 Speaker 1: six feet or one point four meters per hour. Yet 82 00:05:04,480 --> 00:05:07,839 Speaker 1: it is not zero. The architecture of the solar system 83 00:05:08,040 --> 00:05:12,440 Speaker 1: will be subtly altered. He says that while this doesn't 84 00:05:12,520 --> 00:05:16,840 Speaker 1: have any immediate importance, it is symbolic. Quote. There are 85 00:05:16,880 --> 00:05:20,039 Speaker 1: those who will thrill to this stepping out of humanity. 86 00:05:20,560 --> 00:05:23,240 Speaker 1: There are others who will say, not again, must we 87 00:05:23,320 --> 00:05:27,120 Speaker 1: repeat our environmental mistakes, only now on a far larger scale. 88 00:05:28,560 --> 00:05:31,040 Speaker 1: Note that even an asteroid as small as di Morphus 89 00:05:31,200 --> 00:05:33,400 Speaker 1: could do a lot of damage if it struck Earth. 90 00:05:33,880 --> 00:05:36,800 Speaker 1: It's punique compared to the massive asteroid that wiped out 91 00:05:36,800 --> 00:05:39,880 Speaker 1: the dinosaurs, whose size has been estimated at about six 92 00:05:39,960 --> 00:05:44,440 Speaker 1: miles or ten kilometers across. But Johnson notes that di 93 00:05:44,600 --> 00:05:48,240 Speaker 1: Morphus is three times the size and possibly five times 94 00:05:48,279 --> 00:05:51,279 Speaker 1: the mass of the asteroid that created the Baringer Crater 95 00:05:51,400 --> 00:05:55,800 Speaker 1: in eastern Arizona some fifty thou years ago. Johnson said 96 00:05:56,160 --> 00:05:59,000 Speaker 1: it would impact with an estimated energy of roughly ten 97 00:05:59,200 --> 00:06:02,560 Speaker 1: mega tons of t NT, larger than any nuclear bomb 98 00:06:02,839 --> 00:06:05,600 Speaker 1: and create a crater of a few miles in diameter 99 00:06:05,760 --> 00:06:09,040 Speaker 1: and a quarter mile in depth. Blast effects might extend 100 00:06:09,080 --> 00:06:11,640 Speaker 1: for a hundred and fifty miles in all directions from 101 00:06:11,640 --> 00:06:15,279 Speaker 1: the impact site, and the prospect of such disaster makes 102 00:06:15,320 --> 00:06:19,159 Speaker 1: it conceivable that some future asteroid defense mission might need 103 00:06:19,240 --> 00:06:23,880 Speaker 1: to target an object of dimorphous size. If dart Works 104 00:06:23,880 --> 00:06:27,120 Speaker 1: is planned, Johnson said it will validate both the kinetic 105 00:06:27,160 --> 00:06:30,960 Speaker 1: impact or technique for planetary defense purposes and that current 106 00:06:31,000 --> 00:06:35,760 Speaker 1: technology enables our ability to perform the deflection, but that 107 00:06:35,839 --> 00:06:39,160 Speaker 1: doesn't mean that NASA will rush to build more spacecraft 108 00:06:39,240 --> 00:06:43,520 Speaker 1: that can perform the same feat Johnson explained a significant 109 00:06:43,560 --> 00:06:47,560 Speaker 1: asteroid impact is an extremely rare natural disaster, and what 110 00:06:47,760 --> 00:06:50,760 Speaker 1: techniques might be used to deflect one detected in advance 111 00:06:50,960 --> 00:06:54,880 Speaker 1: would be very scenario dependent, especially on how many years 112 00:06:54,920 --> 00:06:58,120 Speaker 1: in advance it was discovered. The decades may pass before 113 00:06:58,160 --> 00:07:01,000 Speaker 1: the next major impact or is discovered, and the planetary 114 00:07:01,040 --> 00:07:03,960 Speaker 1: defense program of that time in the future may want 115 00:07:03,960 --> 00:07:06,800 Speaker 1: to use the more advanced technology that will likely be 116 00:07:06,839 --> 00:07:12,880 Speaker 1: available by then. Today's episode is based on the article 117 00:07:13,120 --> 00:07:16,200 Speaker 1: NASA's Dark Mission is humans first attempt to adjust the 118 00:07:16,240 --> 00:07:19,400 Speaker 1: cosmos on how stuff works? Dot com written by Patrick J. Keiger. 119 00:07:19,920 --> 00:07:22,240 Speaker 1: Brainstuff is production of I heart Radio in partnership with 120 00:07:22,280 --> 00:07:24,640 Speaker 1: houstff Works dot com and is produced by Tyler Klang 121 00:07:24,720 --> 00:07:27,760 Speaker 1: with assistance by Ramsey Young. Four more podcasts from my 122 00:07:27,800 --> 00:07:30,840 Speaker 1: heart Radio. Visit the I heart Radio app, Apple Podcasts, 123 00:07:30,920 --> 00:07:32,680 Speaker 1: or wherever you listen to your favorite shows.