1 00:00:02,320 --> 00:00:07,080 Speaker 1: Welcome to brain Stuff, a production of I Heart Radio, Hey, 2 00:00:07,160 --> 00:00:10,600 Speaker 1: brain Stuff learned Boba bam here. Our knowledge of the 3 00:00:10,680 --> 00:00:15,200 Speaker 1: universe is always expanding, much like the universe itself. This 4 00:00:15,320 --> 00:00:18,480 Speaker 1: means that we occasionally discover something new or come up 5 00:00:18,480 --> 00:00:20,759 Speaker 1: with a new model to explain data that we didn't 6 00:00:20,800 --> 00:00:25,959 Speaker 1: quite understand before. One such astronomical phenomena is the magnetar 7 00:00:26,440 --> 00:00:29,280 Speaker 1: type of powerful neutron star, the existence of which was 8 00:00:29,320 --> 00:00:34,919 Speaker 1: first proposed in that year astronomers suggested that certain blasts 9 00:00:34,920 --> 00:00:38,280 Speaker 1: of gamma and X ray radiation and radio pulses might 10 00:00:38,320 --> 00:00:43,400 Speaker 1: be explained by stars with exceptionally powerful magnetic fields. Since then, 11 00:00:43,479 --> 00:00:47,240 Speaker 1: astronomers have identified dozens of such magnetars in and around 12 00:00:47,280 --> 00:00:51,000 Speaker 1: the Milky Way. If you're curious about what a magnetar is, 13 00:00:51,200 --> 00:00:53,480 Speaker 1: how they come to exist in the galaxy, and why 14 00:00:53,520 --> 00:00:56,920 Speaker 1: astronomers consider them among the scariest objects in the universe, 15 00:00:57,280 --> 00:01:00,680 Speaker 1: this episode is for you. First, let's talk about how 16 00:01:00,760 --> 00:01:04,080 Speaker 1: magnetars are born. The stars go through a life cycle, 17 00:01:04,240 --> 00:01:07,000 Speaker 1: like everything else in the universe. What happens to a 18 00:01:07,040 --> 00:01:09,040 Speaker 1: star at the end of its life depends on the 19 00:01:09,080 --> 00:01:12,840 Speaker 1: mass of the star. For example, our sun is expected 20 00:01:12,880 --> 00:01:16,040 Speaker 1: to grow into a red giant, then become a planetary nebula, 21 00:01:16,319 --> 00:01:20,279 Speaker 1: then turn into a white dwarf star. More massive stars 22 00:01:20,319 --> 00:01:24,839 Speaker 1: can explode into supergiants, erupt into supernova, and then become 23 00:01:24,959 --> 00:01:29,479 Speaker 1: either a neutron star or a black hole. Magnetars are 24 00:01:29,480 --> 00:01:32,440 Speaker 1: the remnants of those massive stars which have exploded in 25 00:01:32,480 --> 00:01:37,160 Speaker 1: a supernova and collapsed into a neutron star. While astronomers 26 00:01:37,200 --> 00:01:39,920 Speaker 1: don't yet know what causes a supernova to result in 27 00:01:39,959 --> 00:01:43,080 Speaker 1: a magnetar instead of a normal neutron star or pulsar, 28 00:01:43,440 --> 00:01:45,840 Speaker 1: some hypothesize that it has to do with the original 29 00:01:45,880 --> 00:01:51,200 Speaker 1: stars rotational speed. In any case, magnetars are neutron stars 30 00:01:51,200 --> 00:01:53,960 Speaker 1: with magnetic fields of approximately tend to the power of 31 00:01:54,040 --> 00:01:57,680 Speaker 1: thirteen to tend to the power of fifteen gals, which 32 00:01:57,720 --> 00:02:01,200 Speaker 1: is a measure of magnetic density. This is a scale 33 00:02:01,200 --> 00:02:04,680 Speaker 1: of magnetic power that's hard to conceive, but let's just 34 00:02:04,720 --> 00:02:08,000 Speaker 1: say that magnetars are considered to be the most powerful 35 00:02:08,080 --> 00:02:12,680 Speaker 1: magnetic objects in the known universe. Scientists have confirmed the 36 00:02:12,680 --> 00:02:16,120 Speaker 1: presence of twenty three known magnetars, and another six are 37 00:02:16,200 --> 00:02:19,080 Speaker 1: waiting additional data to confirm if they meet the criteria 38 00:02:19,160 --> 00:02:22,160 Speaker 1: to be considered. Many of these are located in the 39 00:02:22,160 --> 00:02:26,080 Speaker 1: Milky Way, but don't worry, none are close to Earth. 40 00:02:26,520 --> 00:02:29,600 Speaker 1: The nearest is about nine thousand light years away in 41 00:02:29,639 --> 00:02:33,440 Speaker 1: the constellation Karina, another is some twenty thousand light years 42 00:02:33,440 --> 00:02:36,760 Speaker 1: away in Aquila, and yet another is about fifty thousand 43 00:02:36,840 --> 00:02:41,480 Speaker 1: light years away in Sagittarius. These distances are obviously far 44 00:02:41,600 --> 00:02:44,839 Speaker 1: beyond anywhere we've explored in our galaxy or even sent 45 00:02:44,919 --> 00:02:48,520 Speaker 1: probes like Voyager one or two to visit. While the 46 00:02:48,560 --> 00:02:51,400 Speaker 1: stellar life cycle that leads to a magnetar can take 47 00:02:51,520 --> 00:02:55,480 Speaker 1: millions or billions of years, magnetars themselves have a relatively 48 00:02:55,520 --> 00:02:59,200 Speaker 1: short cosmic life. The magnetic field of a magnetar begins 49 00:02:59,200 --> 00:03:02,799 Speaker 1: to decay after roughly ten thousand years. This means that 50 00:03:02,840 --> 00:03:05,440 Speaker 1: the magnetars that we see in our galaxy today are 51 00:03:05,560 --> 00:03:08,560 Speaker 1: just a few of the many magnetars that have ever existed. 52 00:03:08,840 --> 00:03:11,239 Speaker 1: The scientists estimate that there may be as many thirty 53 00:03:11,280 --> 00:03:15,760 Speaker 1: million inactive magnetars in the Milky Way alone. Okay, but 54 00:03:15,880 --> 00:03:19,320 Speaker 1: how do magnetars compare with the power of black holes? 55 00:03:20,040 --> 00:03:22,680 Speaker 1: Black holes are also certainly not the kind of thing 56 00:03:22,680 --> 00:03:25,840 Speaker 1: would want close to Earth before the article. This episode 57 00:03:25,880 --> 00:03:28,080 Speaker 1: is based on How's to works book by email with 58 00:03:28,120 --> 00:03:31,040 Speaker 1: Phil Plate, the astronomer who shares his insights, and the 59 00:03:31,040 --> 00:03:34,920 Speaker 1: Moniker Bad astronomer. He explained that it depends on what 60 00:03:35,120 --> 00:03:38,640 Speaker 1: force you're measuring. Quote, the gravity from the black hole 61 00:03:38,680 --> 00:03:41,920 Speaker 1: will always be stronger because the lowest mass black hole 62 00:03:42,080 --> 00:03:45,160 Speaker 1: is always more massive than the most massive neutron star, 63 00:03:46,040 --> 00:03:49,560 Speaker 1: but the magnetism of the magnetar will be stronger. In general, 64 00:03:50,640 --> 00:03:53,520 Speaker 1: Luckily will never have to worry about encountering a black 65 00:03:53,520 --> 00:03:57,200 Speaker 1: hole or magnetar close to Earth, but both could theoretically 66 00:03:57,240 --> 00:04:01,040 Speaker 1: impact us here on Earth even from far away. Plate said, 67 00:04:01,280 --> 00:04:04,280 Speaker 1: if a stellar mass black hole eats something, it could 68 00:04:04,320 --> 00:04:07,560 Speaker 1: blast out radiation, but even then I doubt it would 69 00:04:07,560 --> 00:04:10,440 Speaker 1: be as strongly felt from halfway across the galaxy as 70 00:04:10,480 --> 00:04:14,200 Speaker 1: the two thousand four make guitar event. That event was 71 00:04:14,240 --> 00:04:17,320 Speaker 1: a massive gamma and X ray blast from the aforementioned 72 00:04:17,360 --> 00:04:20,880 Speaker 1: magnetard that's fifty thousand light years away in Sagittarius. The 73 00:04:20,880 --> 00:04:23,760 Speaker 1: blast passed over Earth in two thousand four and caused 74 00:04:23,839 --> 00:04:29,320 Speaker 1: disruptions to satellite technology, among other issues. Okay, so magnatars 75 00:04:29,360 --> 00:04:32,880 Speaker 1: are indeed scary, but how present is the threat if 76 00:04:32,920 --> 00:04:36,640 Speaker 1: at all? A Plate said, I am worried about magnetars 77 00:04:36,760 --> 00:04:39,680 Speaker 1: given what happened in two thousand four, the one responsible 78 00:04:39,880 --> 00:04:42,920 Speaker 1: is exceptionally powerful. I don't think that any that strong 79 00:04:42,960 --> 00:04:45,560 Speaker 1: are closer to Earth, but the impact on Earth gets 80 00:04:45,560 --> 00:04:48,720 Speaker 1: stronger with the inverse of the distance squared. If one 81 00:04:48,760 --> 00:04:51,760 Speaker 1: were one fifth that distance, the impact would be twenty 82 00:04:51,800 --> 00:04:56,359 Speaker 1: five times stronger. Not only what a strong magnetar pulse 83 00:04:56,360 --> 00:04:59,800 Speaker 1: effect are electronics and other technology, but one with enough 84 00:05:00,040 --> 00:05:03,560 Speaker 1: length would affect our physiology, including the bioelectricity in our 85 00:05:03,560 --> 00:05:06,359 Speaker 1: bodies and between the atoms that make up everything we know. 86 00:05:07,120 --> 00:05:09,039 Speaker 1: Let's just say we should all be glad, but the 87 00:05:09,120 --> 00:05:21,080 Speaker 1: nearest known magnentar is nine thousand light years away. Today's 88 00:05:21,120 --> 00:05:23,599 Speaker 1: episode is based on the article why our mag guitar 89 00:05:23,720 --> 00:05:26,040 Speaker 1: is so scary on how stuff works dot Com, written 90 00:05:26,040 --> 00:05:28,520 Speaker 1: by Valerie steam App. Brain Stuff is a production of 91 00:05:28,520 --> 00:05:30,760 Speaker 1: I Heart Radio in partnership with how stuff Works dot Com, 92 00:05:30,800 --> 00:05:33,880 Speaker 1: and it's produced by Tyler Clang. Four more podcasts my 93 00:05:33,960 --> 00:05:37,080 Speaker 1: heart Radio, visit the heart Radio app, Apple Podcasts, or 94 00:05:37,120 --> 00:05:38,920 Speaker 1: wherever you listen to your favorite shows.