1 00:00:00,280 --> 00:00:02,640 Speaker 1: This Day in History Class is a production of iHeartRadio. 2 00:00:04,480 --> 00:00:08,400 Speaker 1: Hello and Welcome to This Day in History Class, a 3 00:00:08,520 --> 00:00:11,680 Speaker 1: show that plumbs the depths of history one day at 4 00:00:11,720 --> 00:00:15,800 Speaker 1: a time. I'm Gabe Lucier and in this episode, we're 5 00:00:15,840 --> 00:00:19,400 Speaker 1: looking at well a hole in the ground. But bear 6 00:00:19,440 --> 00:00:21,759 Speaker 1: with me because it also happens to be one of 7 00:00:21,760 --> 00:00:25,960 Speaker 1: the most important contributions of Soviet era science, as well 8 00:00:25,960 --> 00:00:38,320 Speaker 1: as an impressive feat of engineering prowess and patience. The 9 00:00:38,440 --> 00:00:44,160 Speaker 1: day was May twenty fourth, nineteen seventy, Soviet engineers began 10 00:00:44,280 --> 00:00:49,199 Speaker 1: drilling the deepest man made hole ever dug, known as 11 00:00:49,240 --> 00:00:53,400 Speaker 1: the Cola Super Deep Borehole, it ultimately reached a depth 12 00:00:53,440 --> 00:00:57,560 Speaker 1: of approximately seven and a half miles below the Earth's surface. 13 00:00:58,440 --> 00:01:02,200 Speaker 1: For reference, that's about four thousand feet deeper than the 14 00:01:02,240 --> 00:01:05,360 Speaker 1: deepest point of the ocean and equivalent to the height 15 00:01:05,400 --> 00:01:10,319 Speaker 1: of Mount Everest and Mount Fuji combined. It took the 16 00:01:10,400 --> 00:01:13,759 Speaker 1: Soviets roughly twenty years to dig the hole as deep 17 00:01:13,760 --> 00:01:17,240 Speaker 1: as they did, and while the project was abandoned abruptly 18 00:01:17,319 --> 00:01:20,880 Speaker 1: in nineteen ninety two, more than three decades later, the 19 00:01:20,959 --> 00:01:26,600 Speaker 1: Borehole remains the deepest artificial point on Earth. Before we 20 00:01:26,680 --> 00:01:29,520 Speaker 1: get to why anyone would want to dig such a 21 00:01:29,560 --> 00:01:32,559 Speaker 1: deep hole. Let's talk a little more about the hole 22 00:01:32,640 --> 00:01:36,760 Speaker 1: itself for starters. It was actually a series of holes 23 00:01:36,800 --> 00:01:40,200 Speaker 1: that branched off from a central one. The deepest was 24 00:01:40,240 --> 00:01:44,679 Speaker 1: called SG three, and it stretched about forty thousand, two 25 00:01:44,800 --> 00:01:48,600 Speaker 1: hundred and thirty feet deep into the planet's outermost layer. 26 00:01:49,480 --> 00:01:53,639 Speaker 1: But if you're imagining a yawning, bottomless chasm, think again. 27 00:01:54,000 --> 00:01:57,200 Speaker 1: As the hole is actually only nine inches in diameter, 28 00:01:57,920 --> 00:02:00,840 Speaker 1: there was no risk of falling into it, but scientists 29 00:02:00,920 --> 00:02:03,320 Speaker 1: still could have dropped their keys down there, so they 30 00:02:03,320 --> 00:02:07,240 Speaker 1: had to be careful. The borehole was located, as its 31 00:02:07,360 --> 00:02:12,640 Speaker 1: name suggests, on the Kola Peninsula in northwestern Russia. Drilling 32 00:02:12,800 --> 00:02:16,440 Speaker 1: was conducted there at a scientific research station not far 33 00:02:16,480 --> 00:02:20,800 Speaker 1: from the Norwegian border. As for why the Soviets began 34 00:02:20,919 --> 00:02:23,760 Speaker 1: drilling in the first place, the main reason was for 35 00:02:23,800 --> 00:02:27,800 Speaker 1: the sake of science. Researchers simply wanted to learn more 36 00:02:27,880 --> 00:02:30,680 Speaker 1: about the Earth's crust, including what it was made of 37 00:02:31,000 --> 00:02:35,040 Speaker 1: and how it had formed and changed over time. Extracting 38 00:02:35,120 --> 00:02:38,400 Speaker 1: resources like fossil fuels wasn't a part of the mission, 39 00:02:38,639 --> 00:02:41,880 Speaker 1: but the Soviets did collect rock samples, which in some 40 00:02:41,960 --> 00:02:45,040 Speaker 1: cases proved just as interesting as the ones NASA was 41 00:02:45,080 --> 00:02:48,760 Speaker 1: bringing back from the Moon, and speaking of the moon landing, 42 00:02:49,120 --> 00:02:52,359 Speaker 1: that ties in with the other reason the Soviets were 43 00:02:52,400 --> 00:02:56,680 Speaker 1: so intent on digging the deepest hole possible bragging rights. 44 00:02:57,639 --> 00:03:01,520 Speaker 1: The US had overtaken the USSA are in the space race, 45 00:03:01,880 --> 00:03:03,959 Speaker 1: but the race to the center of the Earth was 46 00:03:04,000 --> 00:03:07,360 Speaker 1: still anyone's game in the eyes of the press and 47 00:03:07,440 --> 00:03:11,000 Speaker 1: the public. Digging a hole was far less flashy than 48 00:03:11,120 --> 00:03:15,760 Speaker 1: space exploration, but both superpowers were still eager to claim 49 00:03:15,800 --> 00:03:20,880 Speaker 1: whatever glory there was in conquering the deep frontier. In 50 00:03:20,960 --> 00:03:24,600 Speaker 1: nineteen fifty eight, the US launched its own Cold War 51 00:03:24,680 --> 00:03:30,240 Speaker 1: drilling operation, known as Project Mohole. Its rather lofty goal 52 00:03:30,639 --> 00:03:33,760 Speaker 1: was to reach the Earth's mantle, the layer beneath the 53 00:03:33,800 --> 00:03:36,920 Speaker 1: planet's crust, by drilling deep into the floor of the 54 00:03:36,920 --> 00:03:42,520 Speaker 1: Pacific Ocean, where the crust is thinner. Unfortunately, progress was slow, 55 00:03:42,840 --> 00:03:46,560 Speaker 1: and in nineteen sixty six, Congress cut the project's funding 56 00:03:46,800 --> 00:03:49,360 Speaker 1: after learning the drillers had only gone a tenth of 57 00:03:49,400 --> 00:03:54,000 Speaker 1: a mile after roughly eight years on the job. Meanwhile, 58 00:03:54,200 --> 00:03:58,080 Speaker 1: in the Soviet Union, plans were proceeding much more smoothly 59 00:03:58,360 --> 00:04:03,320 Speaker 1: thanks to several closely guard did technical advances. Drilling officially 60 00:04:03,400 --> 00:04:07,520 Speaker 1: began on May twenty fourth, nineteen seventy, and would continue 61 00:04:07,600 --> 00:04:12,520 Speaker 1: with occasional pauses until nineteen ninety two. At first, the 62 00:04:12,560 --> 00:04:16,839 Speaker 1: team employed a modified drilling rig used for drilling oil wells, 63 00:04:17,440 --> 00:04:21,000 Speaker 1: then in nineteen seventy four it upgraded to a purpose 64 00:04:21,080 --> 00:04:24,360 Speaker 1: built rig installed on site to allow them to dig 65 00:04:24,400 --> 00:04:28,839 Speaker 1: even deeper. The crew made many surprising discoveries the deeper 66 00:04:28,880 --> 00:04:32,040 Speaker 1: they went, including the presence of water, which had been 67 00:04:32,080 --> 00:04:35,760 Speaker 1: thought impossible due to the impermeability of the rock layer 68 00:04:35,839 --> 00:04:40,080 Speaker 1: above it. The biggest surprise, though, by far, was the 69 00:04:40,120 --> 00:04:45,080 Speaker 1: discovery of more than a dozen species of fossilized micro organisms, 70 00:04:45,520 --> 00:04:48,480 Speaker 1: many of which were more than two billion years old. 71 00:04:49,120 --> 00:04:53,120 Speaker 1: Those relics of ancient life were found four miles beneath 72 00:04:53,160 --> 00:04:56,359 Speaker 1: the surface, raising all kinds of questions about how the 73 00:04:56,400 --> 00:05:00,440 Speaker 1: creatures could have survived the extreme pressures and tempered of 74 00:05:00,480 --> 00:05:04,120 Speaker 1: those depths, and whether any other life forms still might. 75 00:05:05,520 --> 00:05:08,720 Speaker 1: As you might imagine, drilling deep into the earth and 76 00:05:08,800 --> 00:05:13,320 Speaker 1: finding signs of life spurred some wild rumors amongst the locals. 77 00:05:14,240 --> 00:05:17,720 Speaker 1: The most persistent claim was that the scientists had drilled 78 00:05:17,720 --> 00:05:21,240 Speaker 1: into an extremely hot cavern by mistake, and when they 79 00:05:21,279 --> 00:05:24,880 Speaker 1: lowered a microphone to investigate, they heard what sounded like 80 00:05:25,000 --> 00:05:29,200 Speaker 1: tortured screams. Of course, that was all an urban legend, 81 00:05:29,480 --> 00:05:32,080 Speaker 1: but to this day you'll still find some folks in 82 00:05:32,120 --> 00:05:35,480 Speaker 1: the region who insist the borehole is really an entrance 83 00:05:35,480 --> 00:05:39,159 Speaker 1: to hell, though again, with only a nine inch diameter, 84 00:05:39,400 --> 00:05:42,040 Speaker 1: you'd have to be a pretty skinny demon to slip 85 00:05:42,080 --> 00:05:46,760 Speaker 1: through it. The Kola Super Deep Borehole was supposed to 86 00:05:46,800 --> 00:05:50,000 Speaker 1: go as deep as possible, ideally all the way to 87 00:05:50,080 --> 00:05:53,440 Speaker 1: the Earth's mantle, some twenty five miles beneath the surface 88 00:05:54,200 --> 00:05:57,280 Speaker 1: in the end, though after almost twenty years of drilling, 89 00:05:57,520 --> 00:05:59,760 Speaker 1: the Soviets only made it about a third of the 90 00:05:59,760 --> 00:06:03,480 Speaker 1: way there. Part of the reason the project was halted 91 00:06:03,800 --> 00:06:06,320 Speaker 1: was due to the collapse of the Soviet Union and 92 00:06:06,360 --> 00:06:09,599 Speaker 1: all the political and economic turmoil that came with it, 93 00:06:10,200 --> 00:06:13,560 Speaker 1: but there were other factors as well. For one thing, 94 00:06:13,839 --> 00:06:16,000 Speaker 1: the temperatures at the bottom of the seven and a 95 00:06:16,040 --> 00:06:21,240 Speaker 1: half mile whole far exceeded expectations. The team had anticipated 96 00:06:21,320 --> 00:06:24,719 Speaker 1: heat of about one hundred degrees celsius or two hundred 97 00:06:24,760 --> 00:06:29,040 Speaker 1: and twelve degrees fahrenheit, but instead temperatures soared to one 98 00:06:29,160 --> 00:06:33,480 Speaker 1: hundred and eighty degrees celsius or three sixty five fahrenheit, 99 00:06:33,920 --> 00:06:37,279 Speaker 1: nearly twice as hot as their models had predicted. Not 100 00:06:37,400 --> 00:06:40,280 Speaker 1: only was that hot enough to deform the drill bits 101 00:06:40,320 --> 00:06:43,760 Speaker 1: and other apparatus, it was also hot enough to cause 102 00:06:43,760 --> 00:06:48,200 Speaker 1: a change in the rocks themselves. The scientists reported that 103 00:06:48,320 --> 00:06:52,080 Speaker 1: rocks below the first fifteen thousand feet behaved more like 104 00:06:52,200 --> 00:06:56,200 Speaker 1: plastic than solid rock. They were more porous and permeable 105 00:06:56,320 --> 00:06:59,000 Speaker 1: than the rocks found farther up, and combined with the 106 00:06:59,040 --> 00:07:02,760 Speaker 1: high temperatures that made drilling through them next to impossible. 107 00:07:03,279 --> 00:07:06,280 Speaker 1: With no clear way forward and future funding up in 108 00:07:06,320 --> 00:07:09,880 Speaker 1: the air, the scientists and engineers at COLA had no 109 00:07:10,000 --> 00:07:13,200 Speaker 1: choice but to call it quits. Data produced by the 110 00:07:13,280 --> 00:07:16,440 Speaker 1: drilling project continued to be studied at COLA for the 111 00:07:16,480 --> 00:07:20,440 Speaker 1: next several years, but eventually the research station was closed 112 00:07:20,440 --> 00:07:24,400 Speaker 1: completely and the borehole was sealed with a heavy metal cap. 113 00:07:25,640 --> 00:07:29,320 Speaker 1: The abandoned dig site has since become a popular destination 114 00:07:29,520 --> 00:07:32,880 Speaker 1: for eccentric tourists, but since you can't actually look into 115 00:07:32,880 --> 00:07:35,880 Speaker 1: the hole itself, you might be better off visiting the 116 00:07:35,960 --> 00:07:40,240 Speaker 1: nearby mining town of Zapple. Yarny its home to the 117 00:07:40,320 --> 00:07:44,320 Speaker 1: Coola Core Repository, which displays many of the rock samples 118 00:07:44,360 --> 00:07:49,119 Speaker 1: recovered during the drilling. Unlike the space race, nobody really 119 00:07:49,200 --> 00:07:52,160 Speaker 1: won the race to the Earth's mantle. There have been 120 00:07:52,200 --> 00:07:55,960 Speaker 1: a few promising efforts over the years, including drilling projects 121 00:07:56,040 --> 00:07:59,840 Speaker 1: led by Germany and Japan, but as of twenty twenty three, 122 00:08:00,320 --> 00:08:03,960 Speaker 1: Lacola Super Deep Borehole is still the one to beat. 123 00:08:06,160 --> 00:08:09,680 Speaker 1: I'm Gabe Lucier and hopefully you now know a little 124 00:08:09,680 --> 00:08:13,520 Speaker 1: more about history today than you did yesterday. You can 125 00:08:13,600 --> 00:08:17,400 Speaker 1: learn even more about history by following us on Twitter, Facebook, 126 00:08:17,440 --> 00:08:22,200 Speaker 1: and Instagram at TDI HC Show, and if you have 127 00:08:22,280 --> 00:08:24,960 Speaker 1: any comments or suggestions, you can always send them my 128 00:08:25,040 --> 00:08:29,320 Speaker 1: way by writing to this Day at iHeartMedia dot com. 129 00:08:29,400 --> 00:08:32,400 Speaker 1: Thanks to Chandler Mays and Ben Hackett for producing the show, 130 00:08:32,559 --> 00:08:34,960 Speaker 1: and thanks to you for listening. I'll see you back 131 00:08:35,000 --> 00:08:50,120 Speaker 1: here again tomorrow for another day in History class.