1 00:00:00,120 --> 00:00:01,960 Speaker 1: This Day in History Class is a production of I 2 00:00:02,040 --> 00:00:07,680 Speaker 1: Heart Radio. Hi, I'm Eves, and Welcome to This Day 3 00:00:07,680 --> 00:00:11,520 Speaker 1: in History Class, a show that uncovers history one day 4 00:00:11,600 --> 00:00:25,080 Speaker 1: at a time. Today is August. The day was August 5 00:00:25,520 --> 00:00:30,520 Speaker 1: nineteen seventy seven, the Big Ear radio telescope at Ohio 6 00:00:30,640 --> 00:00:34,560 Speaker 1: State University received a signal that seemed like it may 7 00:00:34,600 --> 00:00:39,960 Speaker 1: have had an extraterrestrial origin. In nineteen fifty nine, Cornell 8 00:00:40,080 --> 00:00:44,880 Speaker 1: University scientists Philip Morrison and Jiuzeppe Colconi published a paper 9 00:00:44,920 --> 00:00:50,440 Speaker 1: in Nature called Searching for Interstellar Communications. In the paper, 10 00:00:50,760 --> 00:00:55,200 Speaker 1: the scientists proposed that extraterrestrial beings trying to communicate with 11 00:00:55,280 --> 00:01:00,640 Speaker 1: Earth might do so using radio signals. Further, it was 12 00:01:00,720 --> 00:01:04,080 Speaker 1: likely that they would communicate at a frequency of fourteen 13 00:01:04,080 --> 00:01:09,080 Speaker 1: twenty mega hurts Hydrogen, the most common chemical element in 14 00:01:09,120 --> 00:01:14,360 Speaker 1: the universe, amidst photons at this frequency. The quiet band 15 00:01:14,360 --> 00:01:18,320 Speaker 1: of the electromagnetic spectrum between fourteen twenty mega hurts and 16 00:01:18,440 --> 00:01:22,440 Speaker 1: sixteen seventy megaheurts later became known as the water hole, 17 00:01:22,920 --> 00:01:27,399 Speaker 1: a place where extraterrestrials may be likely to communicate. The 18 00:01:27,440 --> 00:01:31,840 Speaker 1: search for Extraterrestrial Intelligence, or SETI, has been happening ever 19 00:01:31,959 --> 00:01:35,840 Speaker 1: since radio technology began developing, but the modern search was 20 00:01:35,880 --> 00:01:40,080 Speaker 1: born in nineteen sixty with Project Osma, when astronomer Frank 21 00:01:40,280 --> 00:01:43,480 Speaker 1: Drake used a radio telescope to examine stars in the 22 00:01:43,520 --> 00:01:48,960 Speaker 1: water hole. In nineteen seventy three, scientists at Ohio State 23 00:01:49,040 --> 00:01:53,600 Speaker 1: University began using a radio telescope named big Ear to 24 00:01:53,720 --> 00:01:59,600 Speaker 1: search for extraterrestrial intelligence. Around eleven sixteen pm Eastern daylight 25 00:01:59,640 --> 00:02:03,800 Speaker 1: time in August fift nineteen seventy seven, Big Air got 26 00:02:03,840 --> 00:02:07,520 Speaker 1: a narrow band foot signal that lasted seventy two seconds. 27 00:02:08,760 --> 00:02:12,880 Speaker 1: The signals seemed to come from the constellation Sagittarius. It 28 00:02:12,960 --> 00:02:16,200 Speaker 1: was about thirty times stronger than the cosmic background noise, 29 00:02:16,639 --> 00:02:19,640 Speaker 1: and it was at a frequency of about fourteen twenty 30 00:02:19,720 --> 00:02:24,360 Speaker 1: mega hurts. The signal went unnoticed until a few days later, 31 00:02:24,760 --> 00:02:28,160 Speaker 1: when astronomer Jerry Aman was reviewing the computer print out 32 00:02:28,160 --> 00:02:32,720 Speaker 1: and noticed the sequence six e q U J five 33 00:02:33,200 --> 00:02:37,400 Speaker 1: among a sea of low numbers that represent background noise. 34 00:02:38,480 --> 00:02:40,840 Speaker 1: He used a red pen to circle the sequence and 35 00:02:40,840 --> 00:02:43,800 Speaker 1: wrote wow in the left margin of the print out. 36 00:02:44,840 --> 00:02:48,959 Speaker 1: That's how it became known as the WOW signal. People 37 00:02:49,040 --> 00:02:52,760 Speaker 1: began pointing to the signal as evidence of extraterrestrial life. 38 00:02:53,960 --> 00:02:58,360 Speaker 1: Scientists determined that nothing in the Sagittarius constellation could have 39 00:02:58,480 --> 00:03:02,200 Speaker 1: made the signal, and that it was not a satellite transmission, 40 00:03:02,600 --> 00:03:08,600 Speaker 1: military signal, aircraft signal, or broadcast beam, and scientists conducted 41 00:03:08,680 --> 00:03:13,880 Speaker 1: follow up searches for decades. Astronomer Robert Gray has searched 42 00:03:13,880 --> 00:03:17,360 Speaker 1: for recurrences of the wild signal. He did sell at 43 00:03:17,400 --> 00:03:21,400 Speaker 1: oak Ridge Observatory in Massachusetts, at the Mount Pleasant Radio 44 00:03:21,440 --> 00:03:25,760 Speaker 1: Observatory in Tasmania, and at the Very Large Array Radio 45 00:03:25,800 --> 00:03:31,320 Speaker 1: Astronomy Observatory in New Mexico, but the signal has never repeated. 46 00:03:32,680 --> 00:03:36,600 Speaker 1: The Big Ear Observatory was disassembled in n but the 47 00:03:36,640 --> 00:03:43,000 Speaker 1: search for extraterrestrial intelligence continues today. In researchers suggested that 48 00:03:43,040 --> 00:03:46,400 Speaker 1: the signal was not a sign of extraterrestrial life, but 49 00:03:46,600 --> 00:03:49,760 Speaker 1: a signal generated by a passing comment that was not 50 00:03:49,920 --> 00:03:54,040 Speaker 1: cataloged at the time, but many astronomers do not agree 51 00:03:54,080 --> 00:03:58,720 Speaker 1: with this theory. Exactly where the signal came from remains unexplained. 52 00:03:59,760 --> 00:04:02,000 Speaker 1: I'm each death Cote and hopefully you know a little 53 00:04:02,040 --> 00:04:06,520 Speaker 1: more about history today than you did yesterday. Get more 54 00:04:06,560 --> 00:04:10,920 Speaker 1: notes from history on Twitter, Instagram, and Facebook at t 55 00:04:11,320 --> 00:04:15,360 Speaker 1: d i H the podcast. We'll be back with more 56 00:04:15,400 --> 00:04:25,599 Speaker 1: history tomorrow. For more podcasts from I Heart Radio, visit 57 00:04:25,640 --> 00:04:28,039 Speaker 1: the I heart Radio app, Apple Podcasts, or wherever you 58 00:04:28,080 --> 00:04:29,200 Speaker 1: listen to your favorite shows.