1 00:00:02,040 --> 00:00:07,080 Speaker 1: Welcome to brain stuff from how stuff works, Hey, brain Stuff. 2 00:00:07,120 --> 00:00:11,040 Speaker 1: Lauren vogelbam here imagined standing in a dense woodland. How 3 00:00:11,080 --> 00:00:13,039 Speaker 1: would you know the size and shape of that forest 4 00:00:13,080 --> 00:00:16,000 Speaker 1: from your limited viewpoint? Not seeing the woods for the 5 00:00:16,040 --> 00:00:18,640 Speaker 1: trees is a good analogy for what astronomer's experience when 6 00:00:18,680 --> 00:00:20,960 Speaker 1: trying to assess the shape and size of our Milky 7 00:00:20,960 --> 00:00:24,680 Speaker 1: Way galaxy. We occupy a small star system embedded inside 8 00:00:24,680 --> 00:00:27,000 Speaker 1: the Milky Ways disc. It's not like we can fly 9 00:00:27,080 --> 00:00:30,080 Speaker 1: above the galactic plane to peek at our galaxies overall shape, 10 00:00:30,320 --> 00:00:34,440 Speaker 1: although how cool would that be. Researchers, however, were determined 11 00:00:34,479 --> 00:00:36,440 Speaker 1: to figure out the true shape of the Milky Way 12 00:00:36,640 --> 00:00:40,320 Speaker 1: while staying embedded inside of it, and they have. Here's 13 00:00:40,360 --> 00:00:43,080 Speaker 1: how they did it. A team from the National Astronomical 14 00:00:43,080 --> 00:00:46,040 Speaker 1: Observatories of the Chinese Academy of Sciences that's the n 15 00:00:46,159 --> 00:00:49,519 Speaker 1: a o C and Macquarie University in Australia studied the 16 00:00:49,520 --> 00:00:52,479 Speaker 1: one thousand, three D and thirty nine right pulsating stars 17 00:00:52,520 --> 00:00:55,160 Speaker 1: called CEFIAD variables to create a three D map of 18 00:00:55,200 --> 00:00:58,120 Speaker 1: the disc of our galaxy. What they found came as 19 00:00:58,120 --> 00:01:02,440 Speaker 1: a surprise. We live in a warped galaxy. Astronomer and 20 00:01:02,520 --> 00:01:05,560 Speaker 1: research collaborator Richard de Grace said in a statement, we 21 00:01:05,680 --> 00:01:09,000 Speaker 1: usually think of spiral galaxies as being quite flat, like Andromeda, 22 00:01:09,080 --> 00:01:12,160 Speaker 1: which you can easily see through a telescope. But our 23 00:01:12,160 --> 00:01:15,640 Speaker 1: galaxy isn't like Andromeda. It has an S shaped bend 24 00:01:15,720 --> 00:01:17,960 Speaker 1: that gets more twisted the farther you move away from 25 00:01:17,959 --> 00:01:21,600 Speaker 1: the galactic center. At this bend, the galaxy's gravitational pull 26 00:01:21,640 --> 00:01:24,600 Speaker 1: becomes weaker, making it look like an old vinyl record 27 00:01:24,640 --> 00:01:28,000 Speaker 1: that's become warped. The study, which has been published in 28 00:01:28,000 --> 00:01:31,199 Speaker 1: the journal Nature Astronomy, used data from NASA's Wide Field 29 00:01:31,200 --> 00:01:34,360 Speaker 1: Infrared Survey Explorer to precisely determine the locations of the 30 00:01:34,360 --> 00:01:37,320 Speaker 1: cepheids throughout our galactic disc and turned them into a 31 00:01:37,360 --> 00:01:39,800 Speaker 1: powerful tool to cut through the dust, gas, and other 32 00:01:39,840 --> 00:01:43,720 Speaker 1: stars that are ob scaring our view. Cheniadene, a researcher 33 00:01:43,760 --> 00:01:45,760 Speaker 1: at n AOC and the lead author of the study, 34 00:01:45,800 --> 00:01:48,960 Speaker 1: set in a press release it's notoriously difficult to determine 35 00:01:49,000 --> 00:01:51,200 Speaker 1: distances from the Sun two parts of the Milky Ways 36 00:01:51,200 --> 00:01:53,800 Speaker 1: outer gas disc without having a clear idea of what 37 00:01:53,880 --> 00:01:57,160 Speaker 1: the disc actually looks like. However, we recently published a 38 00:01:57,200 --> 00:02:00,920 Speaker 1: new catalog of well behaved variable stars known as classical cepheids, 39 00:02:01,160 --> 00:02:03,680 Speaker 1: for which distances as accurate as three to five percent 40 00:02:03,760 --> 00:02:07,600 Speaker 1: can be determined. Sepheids are young stars that are four 41 00:02:07,640 --> 00:02:09,680 Speaker 1: to twenty times the mass of our Sun, and they 42 00:02:09,720 --> 00:02:12,440 Speaker 1: live fast and die young, consuming all their fuel in 43 00:02:12,480 --> 00:02:14,880 Speaker 1: the span of only a few million years, all while 44 00:02:14,960 --> 00:02:17,760 Speaker 1: burning up to one hundred thousand times brighter than our star. 45 00:02:18,680 --> 00:02:20,880 Speaker 1: But what they lack in lifespan they make up or 46 00:02:20,919 --> 00:02:23,360 Speaker 1: in regular pulses in brightness that can be used by 47 00:02:23,360 --> 00:02:27,040 Speaker 1: astronomers to accurately measure their distances, and in this case, 48 00:02:27,160 --> 00:02:29,840 Speaker 1: they acted as tracers to map out the warped milky 49 00:02:29,840 --> 00:02:33,359 Speaker 1: Way disc. Although the milky Way doesn't conform to the 50 00:02:33,400 --> 00:02:36,880 Speaker 1: standard flat disc exhibited by other spiral galaxies like Andromeda, 51 00:02:37,160 --> 00:02:40,920 Speaker 1: it's not alone. From earlier observations, the researchers identified a 52 00:02:40,919 --> 00:02:43,880 Speaker 1: dozen other galaxies with a similar S shaped bend, which 53 00:02:43,880 --> 00:02:45,680 Speaker 1: have given them a clue as to why our galaxy 54 00:02:45,760 --> 00:02:48,799 Speaker 1: is warped. Blue Chow, co author of the study, said, 55 00:02:49,160 --> 00:02:52,200 Speaker 1: combining our results with those other observations, we concluded that 56 00:02:52,280 --> 00:02:55,480 Speaker 1: milky ways warped spival pattern is most likely caused by 57 00:02:55,560 --> 00:03:00,520 Speaker 1: torques or rotational forcing by the massive inner disc. Basically, 58 00:03:00,639 --> 00:03:03,240 Speaker 1: the orbital motions in the massive central region of the 59 00:03:03,240 --> 00:03:07,639 Speaker 1: Milky Way gravitationally bully the less massive outer regions, causing 60 00:03:07,680 --> 00:03:11,520 Speaker 1: them to buckle and bend out of shape. Ultimately, this 61 00:03:11,600 --> 00:03:14,040 Speaker 1: new finding could help us better understand the dynamics of 62 00:03:14,120 --> 00:03:17,480 Speaker 1: orbital motions inside the Milky Way, thereby providing a glimpse 63 00:03:17,480 --> 00:03:25,200 Speaker 1: of how our galaxy evolved. Today's episode was written by 64 00:03:25,200 --> 00:03:27,680 Speaker 1: Ian O'Neil and produced by Tyler Clang for iHeart Media 65 00:03:27,720 --> 00:03:29,799 Speaker 1: and How Stuff Works. For more on this and lots 66 00:03:29,800 --> 00:03:32,360 Speaker 1: of other warped topics, visit our home planet, how stuff 67 00:03:32,360 --> 00:03:44,400 Speaker 1: works dot com.