1 00:00:00,080 --> 00:00:03,480 Speaker 1: Hey, history fans, here's a rerun for today, brought to 2 00:00:03,480 --> 00:00:07,440 Speaker 1: you by Tracy V. Wilson. Welcome to this Day in 3 00:00:07,520 --> 00:00:10,360 Speaker 1: History Class from how Stuff Works dot Com and from 4 00:00:10,360 --> 00:00:12,600 Speaker 1: the desk of Stuff you Missed in History Class. It's 5 00:00:12,640 --> 00:00:14,880 Speaker 1: the show where we explore the past one day at 6 00:00:14,880 --> 00:00:17,079 Speaker 1: a time with a quick look at what happened today 7 00:00:17,079 --> 00:00:24,919 Speaker 1: in history. Hello, I'm Holly Fry. Welcome to the podcast. 8 00:00:25,000 --> 00:00:27,360 Speaker 1: I am sitting in for Tracy V. Wilson this week. 9 00:00:28,000 --> 00:00:31,440 Speaker 1: It is December, so if you celebrate Christmas, I hope 10 00:00:31,440 --> 00:00:34,320 Speaker 1: you're having a merry Christmas. But on this day in 11 00:00:34,400 --> 00:00:38,960 Speaker 1: seventeen fifty eight, a very important thing happened. Hallie's comment returned. 12 00:00:39,520 --> 00:00:42,239 Speaker 1: That was important because it had been predicted and it 13 00:00:42,320 --> 00:00:46,040 Speaker 1: confirmed the work that Edmund Halley had been doing. Edmund Halley, 14 00:00:46,159 --> 00:00:49,839 Speaker 1: you will also sometimes hear it pronounced Holly, sometimes Haley, 15 00:00:49,880 --> 00:00:53,040 Speaker 1: but Haley is generally considered wrong, and whether Hallie or 16 00:00:53,080 --> 00:00:55,560 Speaker 1: Holly is correct is a matter of some debate. I'm 17 00:00:55,600 --> 00:00:59,080 Speaker 1: going with Hallie and Edmund Halley first spotted the comment 18 00:00:59,160 --> 00:01:01,960 Speaker 1: that would later be named for him in sixteen eighty two. 19 00:01:02,480 --> 00:01:04,959 Speaker 1: To be clear, this was not the first time this 20 00:01:05,040 --> 00:01:07,440 Speaker 1: comment had been spotted. It was just the first time 21 00:01:07,480 --> 00:01:11,560 Speaker 1: that Edmund Hallie saw it. Comments prior to Hallie's work 22 00:01:11,560 --> 00:01:15,720 Speaker 1: in astronomy were often associated with an assortment of misconceptions. Historically, 23 00:01:16,240 --> 00:01:18,559 Speaker 1: they had been thought to be omens sent by deities, 24 00:01:18,880 --> 00:01:23,000 Speaker 1: harbingers of some sort, or sometimes just unpredictable and unexplained 25 00:01:23,000 --> 00:01:27,360 Speaker 1: anomalies of the sky. In sixteen eighty four, Hallie paid 26 00:01:27,400 --> 00:01:31,160 Speaker 1: a visit to Isaac Newton to discuss issues of celestial motion, 27 00:01:31,720 --> 00:01:34,560 Speaker 1: and this meeting has become in and of itself something 28 00:01:34,560 --> 00:01:38,399 Speaker 1: of a famed moment in astronomy history, a pivotal discussion 29 00:01:38,440 --> 00:01:41,840 Speaker 1: that resulted in an expansion of human knowledge regarding how 30 00:01:41,880 --> 00:01:46,120 Speaker 1: the universe works. Newton, working on some of the ideas 31 00:01:46,120 --> 00:01:48,920 Speaker 1: that he and Hallie had discussed and sort of putting 32 00:01:48,960 --> 00:01:50,880 Speaker 1: together some of the things that he had already been 33 00:01:50,880 --> 00:01:55,280 Speaker 1: working on, eventually published his work Mathematical Principles of Natural 34 00:01:55,280 --> 00:01:59,040 Speaker 1: Philosophy that's also known commonly as Principia, which is an 35 00:01:59,040 --> 00:02:02,720 Speaker 1: abbreviation of its original Latin title and how he actually 36 00:02:02,840 --> 00:02:06,040 Speaker 1: edited prince Shipia, and he paid for his printing. He 37 00:02:06,120 --> 00:02:09,360 Speaker 1: believed in it so much so he became intimately acquainted 38 00:02:09,400 --> 00:02:15,040 Speaker 1: with its contents, including Newton's calculations on elliptical orbits. Edmund 39 00:02:15,040 --> 00:02:18,919 Speaker 1: Halley began meticulously analyzing the orbits of twenty four comet 40 00:02:18,960 --> 00:02:22,680 Speaker 1: sightings that were on record. It was using those calculations 41 00:02:22,720 --> 00:02:25,160 Speaker 1: that Halley noticed that the orbits of the comets that 42 00:02:25,200 --> 00:02:29,359 Speaker 1: had been seen and reported in fifty one and sixteen 43 00:02:29,360 --> 00:02:32,280 Speaker 1: o seven appeared to be the same one that he 44 00:02:32,360 --> 00:02:36,640 Speaker 1: had seen in sixteen eighty two. With additional examination of 45 00:02:36,680 --> 00:02:39,800 Speaker 1: the data he had available, Edmund Halley determined that the 46 00:02:39,840 --> 00:02:42,560 Speaker 1: comment was on an orbit that took about seventy six 47 00:02:42,639 --> 00:02:46,000 Speaker 1: years to circle the Sun, with variables such as planetary 48 00:02:46,040 --> 00:02:49,120 Speaker 1: gravity shifting the time to be slightly longer or shorter, 49 00:02:49,880 --> 00:02:52,760 Speaker 1: and using that information, he then predicted that the comet 50 00:02:52,800 --> 00:02:55,919 Speaker 1: would once again fly by the Earth in late seventeen 51 00:02:56,000 --> 00:03:00,640 Speaker 1: fifty eight or early seventeen fifty nine. When only initially 52 00:03:00,680 --> 00:03:04,120 Speaker 1: made this prediction, he seemed pretty confident about it, writing quote, 53 00:03:04,240 --> 00:03:07,320 Speaker 1: I can undertake confidently to predict the return of the 54 00:03:07,320 --> 00:03:10,960 Speaker 1: comment in seventeen fifty eight, Though over the years his 55 00:03:11,040 --> 00:03:14,720 Speaker 1: language and discussing this whole matter became less assertive. He 56 00:03:14,800 --> 00:03:18,480 Speaker 1: started saying things like I may venture to foretell in 57 00:03:18,520 --> 00:03:22,440 Speaker 1: a preface to discussing his prediction, but throughout he was 58 00:03:22,560 --> 00:03:27,200 Speaker 1: constantly refining his astronomical tables, and eventually he felt fairly 59 00:03:27,240 --> 00:03:29,560 Speaker 1: certain once again of the time frame that he had 60 00:03:29,600 --> 00:03:33,240 Speaker 1: set for the comets predicted return. And there were other 61 00:03:33,280 --> 00:03:37,400 Speaker 1: astronomers working on this idea as well. Alexis Claude Cliaut, 62 00:03:37,520 --> 00:03:40,040 Speaker 1: for example, came to the conclusion that the comment would 63 00:03:40,040 --> 00:03:44,080 Speaker 1: return in seventeen fifty nine, in the spring, not seventeen 64 00:03:44,120 --> 00:03:48,400 Speaker 1: fifty eight. Edmund Halley died in seventeen forty two, so 65 00:03:48,480 --> 00:03:50,520 Speaker 1: he did not live long enough to see if his 66 00:03:50,560 --> 00:03:53,520 Speaker 1: prediction was accurate, and he knew that would be the case, 67 00:03:53,640 --> 00:03:57,000 Speaker 1: and he famously wrote, quote, if it should return according 68 00:03:57,040 --> 00:04:01,560 Speaker 1: to our predictions, impartial posterity will not refused to acknowledge 69 00:04:01,640 --> 00:04:05,440 Speaker 1: that this was first discovered by an Englishman, and just 70 00:04:05,600 --> 00:04:09,280 Speaker 1: as Edmund Halley had predicted, on Christmas seventeen fifty eight, 71 00:04:09,520 --> 00:04:12,520 Speaker 1: the comet was seen in the night sky, and this 72 00:04:12,600 --> 00:04:15,320 Speaker 1: was lauded as a massive validation for the work of 73 00:04:15,360 --> 00:04:20,040 Speaker 1: both Isaac Newton and Edmund Halley. Shortly after the comets 74 00:04:20,120 --> 00:04:24,520 Speaker 1: Christmas Day reappearance, French astronomer Nicola Luis de la Chai, 75 00:04:24,839 --> 00:04:28,279 Speaker 1: who also worked on calculating comet orbits, gave the comet 76 00:04:28,360 --> 00:04:33,400 Speaker 1: Hallie's name. Its official designation is actually one P slash Halle. 77 00:04:34,480 --> 00:04:38,800 Speaker 1: Since the eighteenth century, numerous sightings of astronomical events have 78 00:04:38,920 --> 00:04:42,480 Speaker 1: been determined to have been sightings of Hallie's common The 79 00:04:42,520 --> 00:04:45,719 Speaker 1: oldest documented sighting that is believed to have possibly been 80 00:04:45,760 --> 00:04:49,640 Speaker 1: Halley's commet happened in four sixty six b C and 81 00:04:49,760 --> 00:04:53,120 Speaker 1: was visible from ancient Greece. The next time the comet 82 00:04:53,200 --> 00:04:56,920 Speaker 1: is expected to pass by Earth is the summer of one. 83 00:04:57,920 --> 00:05:00,600 Speaker 1: I want to thank Eve's Jeff Cote or her work 84 00:05:00,760 --> 00:05:03,560 Speaker 1: on the research for this episode, and Casey Pegram and 85 00:05:03,640 --> 00:05:07,320 Speaker 1: Chandler Maze for they're always incredible and professional audio work. 86 00:05:08,120 --> 00:05:09,760 Speaker 1: If you would like to subscribe to the podcast, you 87 00:05:09,760 --> 00:05:12,080 Speaker 1: can do so. You can find This Day in History 88 00:05:12,120 --> 00:05:15,000 Speaker 1: on Apple Podcasts, on the I Heart Radio app, and 89 00:05:15,040 --> 00:05:19,160 Speaker 1: wherever else you get your podcasts. Stick around tomorrow because 90 00:05:19,160 --> 00:05:22,000 Speaker 1: we're gonna talk a little bit about a fairly new 91 00:05:22,360 --> 00:05:23,320 Speaker 1: holiday tradition.