Pod Insights Short History Of... The Manhattan Project About this episode The Manhattan Project was the codename for the US government’s top secret programme to develop the first atomic bomb. At the height of World War Two, America’s top scientists - such as Dr Robert Oppenheimer - raced against Nazi Germany to harness the power of nuclear fission, and ultimately end the war.
But what is the story of the other scientists, soldiers and civilians who brought about the birth of the A-bomb? What role did Albert Einstein play in the project? And what were the consequences when the bomb was finally used?
This is a Short History Of The Manhattan Project.
A Noiser Production, written by Jo Furniss. With thanks to Dr Cameron Reed, a physicist, and the author of ‘Manhattan Project, The Story Of The Century.’
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Transcript 0:01 Speaker 00 If you're building AI agents, you should check out Strands Agents. It's an open source SDK for Python and TypeScript. The idea is simple. Give a model some tools, let it decide what to call and when, and loop until it's done. No chain configs, no graph orchestration, and works with any model provider. It's also open source and built and tested for production agents. Get started at strandsagents.com.
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1:02 Speaker 03 It is approaching 5:00 AM on the 16th of July, 1945. A storm is passing over the desert of New Mexico in the United States of America.
1:15 Speaker 03 This barren area is known as "Jornada del Muerto", or "Dead Man's Route".
1:22 Speaker 03 But today, as lightning splits the sky, it is alive with activity.
1:36 Speaker 03 A man gets out of an army jeep and walks into a bunker.
1:40 Speaker 03 As he enters the room, he finds an atmosphere of tense excitement.
1:46 Speaker 03 They're here to conduct a test that has never been tried before. And it's this man, Dr. Robert Oppenheimer, who is in charge.
2:00 Speaker 03 No one knows what to expect, not even Oppenheimer. But some of his team have taken bets on the possible outcomes. One, they will be blown to bits.
2:12 Speaker 03 Two, the experiment will be a humiliating dud. Or three, its success will change the course of history.
2:25 Speaker 03 At 5:10 a.m., a 20-minute countdown begins.
2:30 Speaker 03 The experiment is the culmination of years of work, undertaken by what is known as the Manhattan Project. This location has been chosen because it is remote, flat, and there is usually very little wind. Three vital factors which prompted Oppenheimer to name this test site Trinity.
2:52 Speaker 03 He peers out through a peephole, cut into the soil bank of the bunker. The shelter stands over five miles from Ground Zero, the actual site of the test, so Oppenheimer can barely see it, but he knows every detail.
3:08 Speaker 03 Out in the desert stands a 100-foot tower upon which rests a strange-looking ball. A metal globe, about the height of a car, it is covered with black wires that loop between shiny nodes dotting its surface. The cables connect to a control panel.
3:27 Speaker 03 This sphere is known as the gadget, a playful name given to the most dangerous object ever created by human hands.
3:39 Speaker 03 A red flare fires into the sky. It signals the five-minute warning.
3:45 Speaker 03 All around the vast test site, at observation posts placed at least 10 miles from the gadget, the men and women working on the project will recognize this as the signal to lie down, arms over their heads, feet pointing towards Ground Zero.
4:03 Speaker 03 Oppenheimer wonders how many will be tempted to watch, how many will panic.
4:10 Speaker 03 A second flare arcs across the sky. Two minutes. It is too late to turn back now.
4:19 Speaker 03 At least the weather forecaster was correct. Crucially, the wind has dropped.
4:25 Speaker 03 Oppenheimer takes hold of a wooden post to steady himself. The last seconds tick down, and then finally, it is time.
4:45 Speaker 03 Everything turns white.
4:48 Speaker 03 Perhaps, this is it. The end of the world.
4:54 Speaker 03 Then the horizon reappears. An intense light unfurls a shimmering carpet across the desert. The sand turns gold, violet, blue.
5:08 Speaker 03 Around Oppenheimer, there are cheers and applause. Wild laughter.
5:14 Speaker 03 He watches as a ball of fire grows into a mushroom cloud. And then, the sound of the explosion hits them.
5:30 Speaker 03 It is followed by a roar of hot wind. Oppenheimer closes his eyes. The test has worked. They have made an atomic bomb.
5:44 Speaker 03 But while the others celebrate, he can only think of a line from a Hindu holy text. "Now I am become death, the destroyer of worlds."
6:06 Speaker 03 The Manhattan Project was the code name for the US government's top-secret program to develop the first atomic bomb. It was a science experiment on an industrial scale, run with military precision at breakneck speed.
6:24 Speaker 03 At the height of World War II, the race was against Nazi Germany, whose scientists were also trying to harness the dangerous power of nuclear fission.
6:36 Speaker 03 The project has become synonymous with one man, the physicist Dr. Robert Oppenheimer, the so-called "father of the atomic bomb."
6:46 Speaker 03 But what is the story of the other scientists, soldiers and civilians, who brought about the birth of the A-bomb? What role did Albert Einstein play in the project? And what were the consequences when the bomb was finally used?
7:00 Speaker 03 I'm John Hopkins. From the Noiser Network, this is A Short History of the Manhattan Project.
7:15 Speaker 03 Far from being the work of just one team, the creation of an atomic weapon is the culmination of several centuries of scientific development.
7:27 Speaker 03 In 1789, a German chemist called Martin Klapprot examines a mineral taken from a silver mine in what is now the Czech Republic. Within this ore, known as pitchblende, Klapprot discovers the oxide of a dense metallic element. He names it uranium, after the newly-discovered planet of Uranus.
7:50 Speaker 03 A century later, French physicist Henri Becquerel notes that uranium salts emit invisible rays of energy, or radiation.
8:01 Speaker 03 Building on his work, the scientist Marie Curie then pioneers research into what she and her husband Pierre call "radioactivity."
8:11 Speaker 03 Curie's conclusion is that the process can occur "inside" an atom. A radical idea, as scientists had previously believed that atoms were the smallest units of matter. The word "atom" even comes from the Greek "atomon," which means "something that cannot be divided."
8:33 Speaker 03 But at a laboratory in Cambridge in 1932, two physicists do just that. John Cockroft and Ernest Walton build a particle accelerator and split a lithium atom by bombarding its nucleus with protons until it splits into two helium nuclei.
8:54 Speaker 03 A few years later, in the late 1930s, chemists in Berlin go one step further and split uranium atoms. But it's their colleague, Dr. Lisa Meitner, who interprets their unexpected results.
9:11 Speaker 03 As a Jewish woman, she has already fled to Sweden to get away from the antisemitic regime of the Nazi Party. Now, in exile and working far from her colleague's lab, she helps to identify a new process they call "nuclear fission."
9:28 Speaker 03 This means not just dividing a single atom, but creating a chain reaction. One neutron causes the nucleus of an atom to divide, which releases more neutrons that cause other nuclei to divide, and so on.
9:45 Speaker 03 The process releases a massive amount of energy. At once, researchers recognize its potential, and not just for the production of power.
9:56 Speaker 03 Dr. Cameron Reed is a physicist and the author of several books, including Manhattan Project: The Story of the Century.
10:05 Speaker 04 So there were research groups in Paris, Berlin, Rome, London, America, that could have stumbled into that. And it was a quasi-accidental discovery. It was late 1938, in Berlin, Germany. So you know, you have Hitler in power. You're within a year of the start of World War II. It was a striking discovery. And so the fact that it released a lot of energy, millions of times the energy of a chemical reaction, and that it also emitted neutrons that could cause a chain reaction, was appreciated very quickly.
10:43 Speaker 04 It only took a matter of weeks before people who were aware of this fact began speculating that a bomb might be possible.
10:58 Speaker 03 One person who understands and fears the potential of nuclear fission is Albert Einstein.
11:06 Speaker 03 In 1938, the world's most famous living scientist is also in exile. A few years earlier, when Adolf Hitler and the Nazi Party came to power in Germany, Einstein was on a visit to America. Due to his Jewish heritage and opposition to Nazi ideology, he decided not to go home. In fact, he would never return to Germany or Europe again.
11:33 Speaker 03 Einstein is just one of hundreds of Jewish scholars forced to leave their homelands and look for refuge at institutions in America, Britain, or other safe havens like Scandinavia.
11:46 Speaker 03 But though displaced, he keeps working. He follows the developments of two former colleagues: Leo Szilard, a Jewish physicist from Hungary, and Enrico Fermi, who fled fascist Italy because his wife was Jewish.
12:01 Speaker 03 They had already come up with a theoretical model for nuclear fission and patented it, but were beaten to a practical experiment by the scholars in Berlin.
12:12 Speaker 04 These people would read each other's papers. Many of them had studied with each other and kept in contact, and there was a lot of communication, you know, within the community. And they'd visit each other's labs, they'd see each other at conferences, so they were well aware of what each other was working on.
12:35 Speaker 03 Based at the University of Chicago, Szilard and Fermi wanted to draw the attention of the US President Franklin D. Roosevelt to their project and warn him that the technology is now in development in Germany. So they enlist the help of their illustrious colleague, Albert Einstein.
12:56 Speaker 04 They were otherwise unknown refugee physicists. How do they get a letter to the president? And so the rationale was that, well, at least the president would recognize Einstein's name. He's going to take that seriously. And so Einstein didn't draft the letter himself. These other guys did, but it was over his signature. There is a similar letter in Britain in the spring of 1940 by two refugee physicists in Birmingham. And this went up to the British Defence Ministry, but their memorandum was much more technically detailed and estimated critical masses and bomb yields.
13:38 Speaker 04 And it was really a draft of technicalities of making a bomb. And in that respect, it was much more detailed than the Einstein letter. And that started the British effort at the same time. It's the same physics in Berlin, or Washington, or London. And so there was a number of efforts started up about that time going in parallel.
14:07 Speaker 03 A month after Einstein sends his letter to President Roosevelt, Germany invades Poland, and Europe is once again at war.
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14:48 Speaker 01 Ryan Reynolds here for Mint Mobile. I don't know if you knew this, but anyone can get the same premium wireless for $15 a month plan that I've been enjoying. It's not just for celebrities, so do like I did and have one of your assistant's assistants switch you to Mint Mobile today. I'm told it's super easy to do at mintmobile.com/switch.
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15:19 Speaker 03 It takes Roosevelt several months to reply to Einstein. But when he writes back, it is with news that he has ordered a study of uranium.
15:27 Speaker 04 Roosevelt seemed to have an intuitive grasp that this could be really important, and that even if it was very speculative to begin with, it can't be ignored. Because, of course, Roosevelt was convinced, obviously, America was going to be in war. And the idea that any country that didn't have such a weapon could not possibly prevail against one that did.
15:53 Speaker 03 Einstein's old friend, Leo Zillard, attends the first meeting of the Advisory Committee on Uranium in Washington, DC on October 21, 1939. Einstein is invited, but declines. And although his letter influenced Roosevelt, it will be the end of Einstein's involvement with the project.
16:15 Speaker 03 Even so, the wheels are now in motion. The US government now funds Zillard and Fermi's project to develop a nuclear reactor. But the preparation of the necessary uranium poses a challenge.
16:31 Speaker 03 The element itself is not rare. It is found naturally in rocks, soil, and even water. But these are trace elements. For commercial quantities, it is necessary to extract the useful element from ore.
16:47 Speaker 03 This process of separating uranium, which can only happen atom by atom, is known as enrichment or purification. When it comes out of the ground, the ore contains two variant forms: uranium-235 and uranium-238. Only the former can be fissioned, and therefore used for weapons. And unfortunately for the scientists, less than 1% of the ore contains uranium-235.
17:22 Speaker 03 Earlier in 1941, however, a chemist called Glenn Seaborg, working at the University of California in Berkeley, finds that when uranium-238 is bombarded with particles and the resulting element is left to decay, it produces another "new" element. At first, this is known simply as "element 94", until, following the Convention of Naming After Planets, Seaborg calls it "plutonium".
17:51 Speaker 03 Plutonium hardly exists in nature, but chemists can make it in the laboratory. They realize that it is fissile. In other words, it can be used to create nuclear fission.
18:06 Speaker 04 I guess the dilemma that's faced is you have these two possibilities: enrichment and creating plutonium, both will be very difficult. Nobody knows what might actually work in reality. We better do both. So that was the decision that was made: to pursue both possibilities. Who knows what the Germans could be doing?
18:32 Speaker 03 Amid all this activity, the clock suddenly starts ticking louder.
18:40 Speaker 03 Early in the morning of December 7, 1941, two waves of Japanese fighter planes drop bombs and torpedoes on American warships in the US base of Pearl Harbor in Hawaii.
18:53 Speaker 03 The attack kills over 2,400 US sailors, other military personnel, and civilians, and drags the Pacific region into the global conflict.
19:08 Speaker 03 With the US now officially at war, Roosevelt accelerates the work of the Iranian Committee. Ten days after Pearl Harbor, the US Army holds the first meeting of what will become known as the Manhattan Project, named after the Army Headquarters in New York City. Its leader, General Leslie Groves, is in charge of the research, military capacity, and security around the development of the world's first atomic bomb. He must deliver all of this in secret, despite eventually employing a staff of scientists, soldiers, and civilians, numbering tens of thousands.
19:47 Speaker 04 The responsibility for this is given to the Army because they had a huge budget. And Groves's position at that time was that he was an engineer and he was in charge of all military construction within the country. So every munitions factory, and fort, and airbase, and airplane factory, he is organizing the contractors for. And his immediately preceding big project had been the construction of the Pentagon. So he knew all these contractors across the country that could take on big jobs and do them on time and on budget and keep the appropriate secrecy. So he was really the driving force of this thing.
20:34 Speaker 03 The pieces of the puzzle Groves must assemble are spread far and wide, literally, in different parts of the country. First, they need to enrich uranium. At a new site in Oak Ridge, Tennessee, they pursue three different processes. To accommodate the huge numbers of staff, a new town springs up, with houses, homes, stores, schools, even theaters and parks. The population skyrockets, and in the early 40s, one specialist plant there claims to be the largest building in the world.
21:10 Speaker 03 The work carried out at Oak Ridge is fundamental to the overall project, isolating the precious explosive core of the future bomb.
21:20 Speaker 04 They weren't efficient processes, they were quite inefficient, so you'd need tons of input material to get a few kilograms ultimately of the desired version of uranium.
21:32 Speaker 03 One method is to use an electromagnetic device called a Calutron. This machinery is usually run by a team of scientists, but the war has led to a shortage of staff. So, around 10,000 young women, mostly high school graduates, are trained up to do the job. Though the purpose of their work is kept top secret even from them.
22:01 Speaker 03 The process of enriching uranium depends on vast quantities of the original uranium ore. Though there are mines in Colorado and Canada, by far the richest and most plentiful source lies in what is at the time, the Belgian Congo. But how to get hold of materials from so far away during wartime? Here, General Groves has a stroke of luck.
22:29 Speaker 03 A Belgian man named Edgar Sendier is an engineer in charge of a uranium mine in the region and is well aware of the potential applications of his product. With Europe at war, he doesn't want the Nazis to get hold of his huge stockpile of uranium ore, so he ships half the entire reserve to a warehouse on Staten Island in New York. In September 1942, Groves sends a lieutenant to Sendier's New York office to explore the possibility of getting ore sent over from Africa. Sendier famously replies that he can have it right away.
23:07 Speaker 03 A thousand tons of it. He's been awaiting the call.
23:12 Speaker 04 There were very rich uranium mines in the Congo. And I think what probably was the main product they were after was radium, you know, for luminous watch dials and that sort of thing. But the two often occur together. And it happened to be a very rich deposit of uranium ore. Seventy-five percent purity or something. You know, what a break for Groves, because here's this stuff readily sitting in a warehouse in New York in drums marked uranium ore that he was able to buy.
23:46 Speaker 03 Groves buys the lot, plus another 3,000 tons that's still waiting at the mine. So, one problem down. But there are many other challenges to overcome. To build an atomic bomb, the scientists need to prove that nuclear fission will work as they expect and that they can control the process. To do that, they need a nuclear reactor.
24:17 Speaker 03 It is December the 2nd, 1942. A young woman in a tweed jacket hurries through the cold morning at the University of Chicago. As a physicist, Dr. Leona Woods is more accustomed to academic lecture halls. But today, her footsteps crunch across the frozen grass of Stag Field, where American football is played. In the past, she sometimes played squash in the courts tucked under the grandstand. Now she works there.
24:49 Speaker 03 She clocks into the facility. Inside is a hive of activity with people bustling and machinery whirring. The squash courts have been taken over for a new purpose: a secret laboratory. In recent months, workers have constructed a prototype nuclear reactor. It comprises 45,000 black graphite bricks stacked up around 22,000 rods of uranium. These are arranged in a complicated lattice that rises 20 feet high.
25:27 Speaker 03 Dr. Woods joins almost fifty other scientists. Their leader, the Italian Dr. Enrico Fermi, approaches and asks Dr. Woods to prepare the specialist equipment that she herself invented.
25:44 Speaker 03 She sits down in front of a bank of switches and counters, ready to record the feed from her boron trifluoride meters that will detect if the test today is successful.
25:56 Speaker 03 Fermi retreats to a viewing platform and orders everyone, except a few men, to leave the area around the reactor.
26:05 Speaker 03 One lone volunteer is ready to start the process of a nuclear chain reaction.
26:14 Speaker 03 Another team of three students stand on top of the device, armed with buckets of cadmium solution. They are effectively firefighters, as the cadmium will absorb neutrons and slow down the reaction if it gets out of hand. At least, that's the theory.
26:34 Speaker 03 Though Dr. Fermi believes he can control the reaction, this is the first time the technology will be tested on this scale.
26:43 Speaker 03 With no radiation shield or cooling system, everyone here must simply trust in his calculations.
26:51 Speaker 03 Now, he gives the word.
26:55 Speaker 03 The volunteer beside the hive slides out a cadmium rod from between the bricks.
27:02 Speaker 03 Everyone holds their breath.
27:05 Speaker 03 Dr. Woods busies herself with adjusting switches and scribbling readings. She can tell that inside the reactor, invisible to the naked eye, alchemy is taking place.
27:20 Speaker 03 Finally, electrical meters start to click.
27:25 Speaker 03 The sound rises to a buzzing hum. Dr. Woods shows Dr. Fermi her findings. Deep inside the graphite structure, a chain reaction is underway.
27:40 Speaker 03 Leaving Dr. Woods to her work, Fermi orders an operator to send a coded telegram to the rest of the Manhattan Project team. As the paper spews from the machine at the other end, it reads, "The Italian navigator has landed in the new world."
28:07 Speaker 04 Nobody had ever built a reactor before. It operated at less power than a flashlight battery, like half a watt. You couldn't light a light bulb with this thing. But it did demonstrate that the theory was correct, that a chain reaction could be created and controlled in such a way as to synthesize the tonyium ultimately, that that would have to be scaled up. To me, it's remarkable that his first reactor produced about half a watt of power. Within two years, that scaled up to three reactors, each running at 250 million watts to get the scale of production. You know, it's like going from a paper airplane to a 787 in two years.
28:51 Speaker 04 You know, it's remarkable.
29:00 Speaker 00 If you're building AI agents, you should check out Strands Agents. It's an open source SDK for Python and TypeScript. The idea is simple. Give a model some tools, let it decide what to call and when, and loop until it's done. No chain convicts, no graph orchestration, and works with any model provider. It's also open source and built and tested for production agents. Get started at strandsagents.com.
29:26 Speaker 01 Ryan Reynolds here for Mint Mobile. I don't know if you knew this, but anyone can get the same premium wireless for $15 a month plan that I've been enjoying. It's not just for celebrities, so do like I did and have one of your assistant's assistants switch you to Mint Mobile today. I'm told it's super easy to do at mintmobile.com/switch.
29:45 Speaker 02 Upfront payment of $45 for three-month plan, equivalent to $15 per month required. Intro rate first three months only, then full price plan options available. Taxes and fees extra. See full terms at mintmobile.com.
29:58 Speaker 03 In order to create the amount of power needed for the Manhattan Project, they need a much larger reactor. Groves orders a new facility to be built in Hanford in Washington State, alongside the Columbia River. Here, the focus is on the synthesis of plutonium, while the other supersite at Oak Ridge in Tennessee works on uranium.
30:20 Speaker 04 He initially considered putting both of these in Tennessee, but then decided that, well, we have two very different processes here. If there's a catastrophe at one of them, it could wipe out the whole thing. And it helped with secrecy in the sense that if somebody had been employed in Tennessee but left, they would not be considered for the site in Washington and vice versa. So it helped them keep things compartmentalized, as he called it.
30:50 Speaker 03 With construction underway, Groves is still putting together his dream team of academics. Around this time, he meets the man who will become known as the father of the atomic bomb.
31:06 Speaker 03 Robert Oppenheimer is a theoretical physicist who was born in New York, partly educated in Germany, and is now working at the University of California in Berkeley. A tall, thin chain smoker with bright blue eyes. He's not only a brilliant scientist, but a polymath. A man who reads poetry and who has learned several languages in order to appreciate literature in its original form.
31:34 Speaker 03 Though not the most senior scientist that Groves meets in his search for a team, he shows a breadth of knowledge and a level of ambition that impresses the general. Soon, he's helping make key decisions.
31:48 Speaker 04 So there is research going on in New York and Chicago and Berkeley, various places, and so Oppenheimer suggested that you need to centralize this work because it's being duplicated in a lot of universities and you really need a centralized lab where all these people can get together. And yes, it would have to be remote and secret, but you need to coordinate this work. And so I guess you could say the rest is history, and Groves picked Oppenheimer to run this.
32:23 Speaker 03 The centralized location is a place called Los Alamos in New Mexico. Nearby is an area known as Ronada del Muerto, or Dead Man's Route. Remote, flat, and almost uninhabited. In other words, a perfect test site for an A-bomb. If they ever get that far.
32:46 Speaker 04 This is right in the middle of nowhere, and there had been a wilderness boys' school there, which they appropriated because it had some buildings to use for housing. But basically, they had to build this lab from scratch. So you have places like Harvard shipping our cyclotrons to Los Alamos to be reassembled and brought into working condition.
33:08 Speaker 04 So to go from that, you know, within a couple of years to probably what was one of the best-equipped research labs in the world, I guess it shows you how serious they were about what was going on.
33:26 Speaker 03 So now, uranium-235 is being produced at Oak Ridge, Tennessee. Plutonium is being synthesized in Hanford, Washington, and at Los Alamos, Oppenheimer and his thousands-strong team work on bomb design.
33:45 Speaker 03 They discover that two different devices will be required to accommodate the contrasting properties of uranium and plutonium.
33:55 Speaker 03 The uranium bomb is relatively simple. Shaped like the barrel of a gun, it holds uranium at the end of a tube, and a conventional explosion inside the cylinder will trigger the chain reaction that leads to an explosion.
34:10 Speaker 04 The simplicity of the uranium bomb was that they were very confident it would work. And they had only enough U-235 for one bomb at that point. And they knew it was going to be weeks and weeks before they had more. So they were confident that one would work. But in the plutonium bomb, where you've got this implosion technique, they had done hundreds of test implosion experiments.
34:34 Speaker 04 But basically, you're trying to arrange explosives to blow inwards symmetrically with chunks of explosives, all within a microsecond of each other. So it was a very tricky job for the electronics people to get this to work. And they felt they just, they were so uncertain about whether that would work, they felt they had to test it. And the plutonium production was ramping up in Hanford, and so they had enough to be able to spare for a test and have enough left for an actual bomb.
35:10 Speaker 03 The complexity of the device requires experts from multiple fields of study. Scientists and civilians, all working together in the remote heat of the New Mexico desert.
35:21 Speaker 04 There was a lot of civilian folks at Los Alamos, not just the engineers, but chemists and metallurgists to cast them into relevant shapes. There was a lot of electronics people, a lot of what would now be called computer programmers. There's that whole division of people who were doing calculations of simulations of, okay, what can we expect from this thing? How much energy should it release? How much destruction would it cause? So there was a large nascent computing effort at Los Alamos. They had meteorologists on staff that were predicting the weather as the test approached. So all kinds of things you wouldn't initially think would be part of a nuclear physics lab.
36:07 Speaker 03 As the months pass, the war drags on. Some at Los Alamos fear that despite all their efforts, they will be too late to produce a weapon in time to change the course of the conflict. Or even worse, the Germans will get there first.
36:26 Speaker 03 The Nazis could produce an atomic bomb and hold the world hostage with just the threat of a nuclear strike. Also, the Germans had a head start. It is already seven years since their scientists first carried out nuclear fission in a laboratory in Berlin.
36:45 Speaker 04 The Germans simply did not get very far. I think there's various reasons. They had a reactor development program, but it involved only a couple hundred people. They'd never achieved an operating reactor, unlike Fermi. And you would think the Germans would be organized about such a thing. In fact, they were rather disorganized. So there wasn't a personality like Groves with that intense organization. And making the upper levels of the government come to realize how significant this could be. Apparently Hitler had been briefed on it, but at a very speculative level. You know, I think it's been estimated that the amount that the Germans spent on their
37:29 Speaker 04 program wasn't even a thousandth of the Manhattan Project.
37:39 Speaker 03 In fact, it will eventually cost the United States over $2 billion to fund the Manhattan Project. It will also depend on the brilliant minds of many of the European and Jewish scientists who have taken refuge in the United States.
37:55 Speaker 03 But for now, staff at all the sites are working against the clock to produce the core materials: uranium and plutonium, and the devices needed to turn them into weapons. In April 1945, President Franklin D. Roosevelt dies of a cerebral hemorrhage while still in office.
38:17 Speaker 03 His vice president, Harry Truman, takes the oath of allegiance the following day, and only then learns about the existence of the project, such is the level of secrecy.
38:29 Speaker 03 In his diary that night, he writes about a weapon great enough to destroy the whole world. He also notes that the Germans probably don't have the resources to develop it, but the Russians might.
38:42 Speaker 03 The Nazis are now close to defeat. And before the month is out, Hitler commits suicide in his Berlin bunker.
38:51 Speaker 03 A week later, Germany surrenders. The war in Europe is over.
39:00 Speaker 03 But Japan vows to fight on.
39:05 Speaker 03 Reluctant to abandon its project of expansion into resource-rich parts of Southeast Asia and the Pacific, it also fears the occupation and loss of cultural independence that could follow should it surrender. As summer approaches, the threat to the United States from across the Pacific remains active. There is no let-up for Groves and Oppenheimer at Los Alamos.
39:31 Speaker 04 By the summer of 1945, they had enough of this variant of uranium for just one bomb. This must be one of the few times in military history where a significant new weapon is deployed without a full-scale test beforehand. The first test was really Hiroshima.
39:56 Speaker 03 In July 1945, the one and only uranium bomb is loaded onto a ship for transport across the ocean to the United States bases in the Pacific. On the very same day, Oppenheimer decides that conditions are right to test the second type of weapon.
40:16 Speaker 03 Plutonium production has been more efficient, so they have enough for a trial run of the more complex device. It will become known as the Trinity Test.
40:27 Speaker 03 In the desert outside Los Alamos, a 100-foot tower is constructed. A sphere containing the plutonium, the so-called gadget, is hoisted onto the platform, and Oppenheimer takes up position in a bunker.
40:41 Speaker 03 Groves is present, as is Fermi, who built the first nuclear reactor. Various personnel at outposts outside a 10-mile exclusion zone make observations. Military aircraft circle to take readings. At 5:30 a.m. on July 16, the world's first atomic bomb is unleashed.
41:08 Speaker 03 The tower holding the gadget is incinerated. The sandy ground around the device is turned into a sheet of green glass.
41:18 Speaker 03 Witnesses as far as 200 miles away see a flash. After the test, a press release is issued, simply stating that a considerable amount of explosive had been detonated, without loss of life or limb.
41:34 Speaker 04 The people were taking bets on whether or not this thing would work. They were taking bets on how much energy it would yield. And so the bets were going from everything from zero to 100 kilotons. And apparently Enrico Fermi alarmed all his colleagues by speculating they could set fire to the atmosphere, which was a total red herring. But I guess it shows you the mindset they were under at the time.
42:00 Speaker 03 Even Oppenheimer himself underestimated the power of the weapon. In the event, the plutonium bomb releases the equivalent of 21 kilotons of TNT. It is hotter than the surface of the sun.
42:18 Speaker 03 The Trinity test of the plutonium weapon is a success, and the uranium device is already on its way across the Pacific. But there are those, even among the scientists, who start to have their doubts about using the weapon against civilians.
42:35 Speaker 03 Under pressure to give the Japanese a warning, on July 26, President Truman issues a notice, the Potsdam Declaration, in which he calls for them to stand down. In addition, leaflets are dropped over Japan, alerting civilians about "the most destructive explosion ever known to man."
42:57 Speaker 03 But the Americans do not categorically spell out that they have a nuclear weapon in their arsenal.
43:04 Speaker 03 When the Japanese ignore the Potsdam Declaration, the US decide to go ahead with a plan to bomb its mainland.
43:17 Speaker 04 They had identified about half a dozen Japanese cities that had not been bombed, that had geography that would let them, you know, test the effects of the bombs were large enough. Hiroshima was a big army base, Japanese army base. So they didn't just drop these things willy-nilly on somebody. They had a list of about half a dozen potentials, and Hiroshima, Nagasaki, Kokura were at the top three. And Nagasaki, I think there's some morbid irony here in the history. Nagasaki was where the torpedo was used at Pearl Harbor had been made.
44:15 Speaker 03 It's 2:45 in the morning of August 6, 1945, on Tinian Island in the Pacific Ocean, around 1,400 miles south of the coast of Japan. After completing his final checks, Colonel Paul Tibbetts is cleared for takeoff. He accelerates his plane down the runway and up into the endless black of the night sky. The propeller plane is a B-29 Super Fortress, modified especially for this mission. The usual armor and guns have been stripped off, otherwise, given today's five-ton payload, it would barely get off the ground.
44:57 Speaker 03 Tibbetts soon has them cruising at an altitude of 36,000 feet. Their only onboard defense is a tail gunner, though they are accompanied by two other B-29s who can provide cover if necessary. Slowly, the sun comes up across the Pacific. The aircraft's lightweight silver plating gleams, its name picked out in black capitals just under Tibbetts' window at his request: Enola Gay, after his mother.
45:35 Speaker 03 After six hours, the crew spot the islands of Japan rising before them.
45:41 Speaker 03 Their target is the city of Hiroshima. As they approach, two weapons experts clamber down into the bombay to make the final activation of the device.
45:53 Speaker 03 It is codenamed Little Boy, even though the black cylinder contains the biggest explosive ever deployed in combat.
46:03 Speaker 03 Bombardier Tom Faraby shouts that he has visual confirmation of the target, a distinctive T-shaped bridge over the river Ota. Tibbetts instructs his crew to put on protective goggles. The hatch opens, and Little Boy drops into the air.
46:23 Speaker 03 As one of the men makes the sign of a cross, Tibbetts puts the B-29 into a sharp 155-degree turn.
46:32 Speaker 03 The crew are thrown side to side until their pilot straightens up and gives the engine full thrust, putting as much distance as possible between them and the explosion.
46:44 Speaker 03 No one knows if the blast will tear the aircraft to shreds. Someone shouts aloud, "1,000, 2,000," counting the seconds of Little Boy's descent.
46:57 Speaker 03 "3,000, 4,000." Radar operator Jacob Besar tracks the bomb with more accuracy on his screen. It is still falling.
47:07 Speaker 03 Will it detonate or not?
47:11 Speaker 03 Enola Gay roars through the air. They keep counting. "30,000, 40,000."
47:20 Speaker 03 The bomb must be a dud. Then, 10 miles and 43 seconds later, the sky turns white.
47:37 Speaker 03 Moments later, the aircraft jerks in the shockwave. It jolts again from an aftershock. Warning lights and alarms sound.
47:47 Speaker 03 But Tibbetts keeps his shaking hands on the stick and flies on.
47:53 Speaker 03 In the tailgun position, Staff Sergeant George Karan raises his camera and snaps a photograph of a purple mushroom cloud boiling upwards into the morning sky.
48:15 Speaker 04 The Hiroshima mission was regarded as a textbook mission. Not all of the crew had been briefed on it. Once they got into flight, then the pilot would describe what, "Okay, this is the first atomic bombs in history." So a lot of the ordinary crew members were only told their final mission when they were in flight. These were all experienced combat crews. A lot of them had been in missions in Europe. And so they knew as soon as this thing went off, and they witnessed it, that this was much more destructive than any ordinary bomb. One bomb was taking out whole square miles of a city. In fact, one of the crew members was keeping a diary. He recorded that
49:00 Speaker 04 when he witnessed the bomb, he wrote, "My God, what have we done?" So this was an experienced combat crew member. So they must have had an immediate sense that this was something very different. This was, this was changing the world.
49:22 Speaker 03 An estimated 80,000 people die in the immediate blast. Almost a third of the population of Hiroshima.
49:31 Speaker 03 Many are killed by a fireball that is hotter than the sun. While others suffer flash burns from a blast wave over two miles in diameter. Thousands more die as buildings collapse and glass shatters.
49:54 Speaker 03 Three days later, the plutonium-fueled bomb called Fat Man is dropped to. This time, however, the mission is less straightforward. The weather is bad, the fuel gauges play up, and cloud cover prevents the bombardier from getting a visual on Kokura, the target city.
50:14 Speaker 03 With fuel running perilously low, they drop the payload when there is a small break in the clouds over Nagasaki. They barely manage to get back to the US airbase in Okinawa.
50:28 Speaker 03 The plutonium weapon is more powerful, but thanks to shelter provided by the city's hilly topography and the fact that the bomb detonates over a less densely populated industrial zone, the number of casualties is about half of those in Hiroshima. Nevertheless, the death toll climbs steadily after the bombings. People succumb to physical injuries like burns. Deaths from radiation sickness peak about three weeks later. In the longer term, people starve due to the destruction of vital infrastructure.
51:03 Speaker 03 The death toll is higher than even the bomb's makers had foreseen. Oppenheimer is quoted as warning that 20,000 could die, but some estimates put the total number at 10 times that amount.
51:21 Speaker 04 They must have known this was going to create immense casualties. You couldn't avoid it. So, you know, you read some of the memoirs of these people and it, there's often a sense of
51:32 Speaker 04 of mixed feelings, that well, you know, pride in that they had contributed something to the end of the war. They had used their experience and knowledge to contribute to this thing, and it worked. And they could take pride in this immense accomplishment, but at the same time, they'd been involved in this horrendous thing.
51:56 Speaker 03 The Japanese surrender six days after the second attack. The following year, President Truman signs the Atomic Energy Act, which puts the nuclear program into civilian control.
52:10 Speaker 03 The Manhattan Project itself is closed in 1947, but dealing with what it leaves behind takes rather longer. Vast amounts of waste were created by the rapid production of radioactive material, with huge tanks used to store it. In the heat of the race to end the war, dealing with these pollutants was put off until later. The complicated cleanup process is ongoing today, one that some estimates claim will cost more than the original venture.
52:46 Speaker 03 But though the Manhattan Project is over, Oppenheimer and his team have let a genie out of the bottle.
52:53 Speaker 03 The US spent billions of dollars to set up industrial-scale nuclear facilities. Despite the end of the war, the reactors keep running, the laboratories keep researching. The United States wins the race to develop an atomic bomb, but they cannot keep guard over the technology forever.
53:14 Speaker 04 Oppenheimer had perhaps hoped that that could be controlled, but the Russians had spies at Los Alamos. They were well aware of what was going on. Stalin was well aware of what was going on and, in fact, instructed his own scientists to begin work. And they had some sketches of the design of the Trinity weapon. So after the end of the war, the Russians got their own reactor operating within about a year, and it took them only four years to reproduce the work. And of course, any country that would have fancied itself as a world power would have felt they'd have to have their own nuclear weapons program. So within a few years, you have Russia, Britain, France, China beginning to pursue these things.
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55:09 Speaker 03 By the 1950s, the ideological opposition between America and Russia has never been more stark. But both now possess atomic weapons. Geopolitical tension ramps up and mistrust grows as both sides fear that the other could be the first to push the button and launch a nuclear strike. Neither superpower can act, held in the stalemate of what becomes known as mutually assured destruction. For his part, Oppenheimer falls out of favor in the aftermath of the war. Telling the media that he feels he has blood on his hands, he becomes unpopular with the White House. In an atmosphere of anti-communist hysteria, his enemies drag up historic connections to left-wing politics
55:54 Speaker 03 and use those to sideline him.
55:57 Speaker 03 But other scientists continue his work. Though their roles have evolved, all three of the main Manhattan Project sites, Oak Ridge in Tennessee, Hanford in Washington, and Los Alamos in New Mexico, are still working today.
56:11 Speaker 03 The American model of large-scale, government-funded research projects carried out by teams of scientists sets a precedent that continues to be known as big science.
56:26 Speaker 04 Prior to the war, there were no federal research grants, or maybe very limited. You know, there was no national institutes of health, or national labs. It was all university-based stuff, and obviously, there was no space program. You know, so that set the template for big science projects like Apollo and the Internet, national laboratories, and National Science Foundation, and all of these really changed the relationship between science and government. It's all that sort of thing hadn't existed previously.
57:07 Speaker 03 With the war that precipitated it now almost out of living memory, it's no easier to balance the ledger of the Manhattan Project.
57:18 Speaker 03 Though it put an end to a bloody conflict that would have doubtless cost many more lives, by dropping just two bombs, it caused the deaths of around 200,000 Japanese civilians. And while the work of the Manhattan Project led to developments in nuclear power, medicine, and other applications, the debate around whether the dawn of the nuclear age is a positive for mankind continues to divide opinion.
57:46 Speaker 04 It changed the world. So suddenly, you have a weapon now that could take out a large city with a single blow. Oppenheimer likened it to two scorpions trapped in a bottle. Each can destroy the other, but only at the cost of themselves. So, you know, I guess it's changed the strategic landscape, you know, just so radically, and it changed how science and government and the military interact. Once it became a huge military-industrial complex, it's far beyond his control. And I guess all of the proliferation on the politics were born on the day of the Trinity Test.
58:35 Speaker 03 Next time on Short History Up, we'll bring you a short history of the Spanish Flu.
58:42 Speaker 07 What sort of impact did the Spanish influenza pandemic have on wider society? Surely, a virus that kills so many people, you know, a quarter of a million people in Britain, 675,000 in the United States, 400,000 in France, 50 to 100 million people worldwide. Surely, people would have remembered that and recorded and built memorials to it. No, none of that happened. It's virtually impossible to find a contemporary memorial to the dead of the Spanish Flu. But then the next question you have to ask yourself, well, how different is that really to what we see today with COVID-19?
59:26 Speaker 07 We've lived through the biggest pandemic in a century. But now, five years later, I get the impression that nobody wants to talk or think about it.
59:37 Speaker 03 That's next time.
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