* President Roosevelt authorized the Manhattan Project to go full steam 26 days after Fermi’s success, on 28 December 1942
* The U.S. would end up spending $2 billion on it. (about $22 billion in 2018 dollars)
* Do you know why it cost so much?
* 130,000 people
* When I thought of the Manhattan Project, I used to imagine it was a handful of guys sitting around a blackboard scribbling equations in chalk.
* Over 90% of the cost was for building factories to produce fissile material, with less than 10% for development and production of the weapons.
* Remember that you couldn’t just go to Amazon and buy pure uranium-235 or plutonium.
* It had to be made. A LOT of it had to be made.
* And they still didn’t even know how to make it.
* So they ran up parallel factories trying various methods.
* Out of that 130,000 people, do you know how many knew they were working on developing an atomic bomb?
* Probably not many.
* It was one of the best kept secrets in military history.
* Imagine – 130,000 people working on a project that didn’t know what it was for!
* And I’m not just talking about the worker bees – the management didn’t know either.
* And of course in December 1942, nobody knew how long the war would last or how long it would take to build a bomb.
* So it was highly likely they the war would be over before they figure it out.
* But they did it anyway.
* While Bush was seeking approval from the president, Oppenheimer had suggested that a bomb laboratory be set up in an isolated area.
* It would operate secretly but allow a free exchange of ideas between theoreticians and experimentalists who would work side by side.
* The site chosen was the Los Alamos Boys Ranch School in New Mexico.
* Which, BTW, used to be called just Mexico.
* The owners of the boys’ school occupying the site was eager to sell, and Groves was equally eager to buy.
* it was easy enough to get to Santa Fe by train, Los Alamos itself was virtually inaccessible, located on a mesa, or flat-topped hill, about 30 miles northwest.
* a private ranch school for boys, modeled after the Boy Scouts
* Famous graduates of the school include William S. Burroughs and Gore Vidal
* The official name for the site during the war was Project Y.
* It was only after the war, when it’s existence became public, that it was referred to as Los Alamos.
* Oppenheimer was put in charge, despite him being a leftie and the fact he didn’t have a Noble Prize when many of the people working in the team did.
* But he was apparently a great leader.
* According to some of the other scientists who worked there, nobody else in that laboratory even came close to him in his knowledge.
* There was human warmth as well.
* Everybody certainly had the impression that Oppenheimer cared what each particular person was doing.
* In talking to someone he made it clear that that person’s work was important for the success of the whole project.
* He seems to have the ability to walk into a room where a major scientific debate was going on, listen, sum up everyone’s points, and then when he left, everyone knew what the right answer was.
* He insisted that everyone at Los Alamos could know everything about the project – they weren’t relegated to their particular piece of the puzzle.
* He created a spirit where everyone felt important and involved.
* Meanwhile, on the production side of things, they still had challenges.
* Huge amounts of material had to be obtained.
* But that’s just the start of their problems.
* More than three million board cubic feet of timber were required, for instance, and the magnets needed so much copper for windings that the Army had to substitute silver, borrowing almost 15,000 tons of silver bullion from the US Treasury.
* They couldn’t get enough vacuum tubes, generators, regulators and other equipment
* Keep in mind that nobody had ever done this before, so they didn’t know what they needed.
* A lot of it was in flux.
* Last-minute design changes continued to frustrate equipment manufacturers – who of course were still kept in the dark about what was going on.
* And there were major performance issues with other parts of the project.
* Oppenheimer discovered that he needed three times more fissionable material would be required for a bomb than earlier estimates had indicated.
* Even if things had been going well with the teams trying to create U235, at Oak Ridge, Tennessee, it was possible that they might not produce enough purified U-235 in time.
* But things weren’t going well.
* The two teams trying to create Uranium 235, one using electromagnetic separation and the other using gaseous diffusion, at Oak Ridge, had equipment malfunctions and breakdowns or just couldn’t get it working.
* Things on that front were behind schedule.
* Even going into 1944, neither method was producing results.
* So Oppenheimer turned to the Navy.
* Even though the bomb project was in the hands of the Army, the Navy were pursuing their own atomic project – to provide a source of fuel for submarines.
* And they were working on a completely different way to create U235 – thermal diffusion.
* This was under a guy called Abelson.
* Oppenheimer suggested Groves go to meet with Abelson and offer to help funds his project if they could share the U235.
* Abelson agreed.
* Abelson had been working with 100 convection columns in his plant.
* In 90 days, Groves had a 2142-column plant built in Oak Ridge.
* There was also a third major facility in Hanford, Washington, run by Du Pont, trying to produce plutonium.
* Interesting story about Hanford.
* It was the location of a booming agricultural town.
* About halfway between Seattle and Spokane.
* But the government came in and gave all 1500 residents eviction notices.
* They were told the government would purchase their properties – mostly farms – at a price to be determined by the government and they had between 2 and 30 days to move.
* People asked why?
* They were told “we can’t tell you. It’s top secret.”
* They were purchased at low prices.
* And they weren’t allowed to harvest their last crops, despite a bumper year with high prices.
* Some farms were leveled while the families were still in the homes.
* One guy remembered his father received $500 for a 10-acre irrigated farm.
* Out of that was deducted back taxes and electricity bills, leaving about $300.
* “The well alone and the irrigation system cost $1,100,” he said.
* Many of the displaced residents believe they are entitled to the same kind of payments that interned Americans of Japanese descent received from the government.
* “The government stole our property,”
* Groves wrote in his memoirs that he regretted paying too much for the farms, a comment that still rankles many survivors.
* Then the government leveled the town except for the high school, which was used for the management offices of the plutonium project.
* DuPont and the army co-ordinated efforts to recruit labourers from all over the country And 50,000 workers were shipped in over the next year.
* a sea of tents and wooden barracks where there was little to do and nowhere to go.
* Ground-breaking for the water-cooling plant for the 100-B pile, took place on 27 August, less than two weeks before Italy’s surrender to the Allies on 8 September.
* On 10 October, work gangs began laying the first of 390 tons of structural steel, 17,400 cubic yards of concrete, 50,000 concrete blocks and 71,000 concrete bricks.
* That was just to make the 40 foot windowless building the pile sat in.
* Groves had a hard time getting Du Pont on board.
* Apparently they had copped some PR flack after WWI for war profiteering.
* founded in July 1802 as a gunpowder mill by French-American chemist and industrialist Éleuthère Irénée du Pont.
* using capital raised in France and gunpowder machinery imported from France.
* The company was started at the Eleutherian Mills, on the Brandywine Creek, near Wilmington, Delaware, two years after he and his family left France to escape the French Revolution and religious persecutions against Huguenot Protestants.
* The company began as a manufacturer of gunpowder, as du Pont noticed that the industry in North America was lagging behind Europe.
* The company grew quickly, and by the mid-19th century had become the largest supplier of gunpowder to the United States military, supplying half the powder used by the Union Army during the American Civil War.
* They went on to develop nylon, Teflon, Mylar, Kevlar, and Lycra among other things.
* Eventually they agreed to help Groves build and operate his plutonium pile for costs plus one dolllar.
* The scientists at Hanford were from The Metallurgical Laboratory (or Met Lab) – a scientific laboratory at the University of Chicago that was established in February 1942 to study plutonium.
* But getting plutonium to go fissile was a different process than uranium.
* The problem was with the firing mechanism.
* Essentially, to detonate an atomic bomb, all you need to do is put together a critical mass which will then explode spontaneously.
* Putting it together must be done rapidly, otherwise predetonation would only produce a small explosion, which would blow the bomb apart before the optimal mass was achieved.
* One way to do this was to use a gun to fire a fissionable projectile into a fissionable target.
* This might work with uranium, but would work with plutonium only if absolute purification of plutonium could be achieved.
* Unable to purify the plutonium sufficiently, bomb designers came up with the idea of using high explosives to compress a sphere of plutonium into a supercritical mass, releasing neutrons and causing a chain reaction.
* However, no one yet knew exactly how much plutonium would be needed.
* Would Hanford be able to produce enough?
* As they tested the plutonium approach later in 1944, they couldn’t get it to create a chain reaction.
* It would start off okay but then the reaction would taper off.
* They eventually figured out it was something they called ‘xenon poisoning’.
* The chain reaction would produce the element xenon, which would then start absorbing neutrons faster than the pile could create them, slowing down the chain reaction.
* On Christmas Day in 1944, the figured out the solution was just increasing the number of tubes containing irradiated uranium slugs.
* By the end of January 1945, they had produced enough plutonium nitrate to send it to Los Alamos.
* Colonel Franklin T. Matthias from Groves’s staff then carried the first small batch of plutonium nitrate by train from Portland to Los Angeles, where he turned it over to a security courier from Los Alamos.
* It arrived there on 2 February.
* After that, small subcritical batches in metal containers within wooden crates were despatched by Army ambulance, in convoy, via Boise, Salt Lake City, Grand Junction and Pueblo to Los Alamos, New Mexico.
* It was also known, theoretically, that it would be possible to create a fusion, or hydrogen, bomb.
* Just as when heavy nuclei break up, or fission, energy is given off, so when light nuclei are forced together by immense temperatures and pressures, they fuse, giving off energy.
* The fusion of hydrogen atoms, producing helium, is the energy that powers the sun.
* If it could be made, a thermonuclear, or fusion, device would be considerably more powerful than either a uranium or plutonium device, though it would need a fission bomb as a detonator.
* Research on the hydrogen bomb – or the Super, as it was called at Los Alamos – was always a distant second in priority, but Oppenheimer thought that it was too important to ignore.
* After considerable deliberation, he gave Edward Teller permission to devote himself to the Super.
* At Los Alamos, Oppenheimer had put together a stellar team of the country’s leading physcists.
* As well as a few British physicists.
* One member of the British contingent was the Soviet agent Klaus Fuchs, who had been passing nuclear information to the Russians since 1942 and continued doing so until 1949 when he was caught and convicted of espionage.
* The problem with the plutonium implosion method was to achieve symmetrical implosions.
* The high-explosive shell would melt the metal core, so it was difficult to compress the material uniformly without some of it squirting out of the side.
* One of they physicists The problem he found was to achieve symmetrical implosions. The high-explosive shell would melt the metal core, so it was difficult to compress the material uniformly without some of it squirting out of the side. Parsons mocked: ‘To my mind he is gradually working up to what I shall refer to as the Beer-Can Experiment. As soon as he gets his explosives properly organized, we will see this done. The point to watch for is whether he can blow in a beer can without splattering the beer.’ called it the Beer-Can Experiment.
* “As soon as he gets his explosives properly organized, we will see this done. The point to watch for is whether he can blow in a beer can without splattering the beer.”
* John Von Neumann and Teller worked out that if you could squeeze a hollow shell of plutonium into a solid ball, you could put together a critical mass much quicker than you could firing it from a gun.
* it would be possible to squeeze a solid subcritical sphere of plutonium to such unearthly densities that it would detonate.
* This would avoid the problems of compressing hollow shells.
* The high speed of the compression would prevent predetonation; the plutonium would not have to be so pure and you would need less of it.
* In other words, you could make a more reliable bomb more quickly.
* It would also be smaller, and therefore much easier to fit in a plane.

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