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Fat Man and Little Boy 1989 drama, history This film is a forgotten gem that puts a human face on one of the most intriguing sagas in modern human history. It's the story of the Manhattan Project -- the massive Allied World War II effort to build the first atom bomb, featuring two key leaders who made it happen, Gen. Leslie Groves (Paul Newman) and Dr. Robert Oppenheimer (Dwight Schultz). The title comes from the code names for the first, and thankfully only, two atomic bombs used in war.  This is a real grown up film that requires your close attention. Do not expect a deluge of advanced science and math, but rather a quick moving storyline about a fast tracked program made more intense by the urgency of world war. Some comments about the film – 1) the movie ends rather abruptly after the Trinity Test. Just as well, we all know what happened with Little Boy and Fat Man, so the movie skips the August 1945 bombing raids on Japan. 2) The movie also does not address the very successful communist spy ring operating at Los Alamo Lab. Stalin would soon have his own atomic bomb; thanks to the American communists traitors. 3) The radiation accident depicted in the film is loosely based on the real life fatal accident on August 21, 1945 of Los Alamos physicist Harry Daghlian while performing criticality experiments. Just like actor John Cusack in the movie, Daghlian was doing a hands-on test when an error caused the plutonium core to go supercritical. Daghlian reached his hand into the intense radiation zone to stop the reaction, and received a massive radiation dose. He went into a coma and died 25 days later. 4) As suggested by the film, Dr. Oppenheimer was deeply troubled by the destructive power of atomic weapons. He resigned his position at Los Alamos Lab soon after the war ended. He later refused to work on the Hydrogen Bomb project, and lost his govt. security clearance. On a personal note, I visited Los Alamos in summer 2019 and toured the excellent science museums. Do not expect to see the rustic, ranch style buildings and dirt roads presented in the film. In fact, all the original 1940’s vintage buildings were declared contaminated and unsafe. The entire town was demolished and sent to a waste disposal site. In the old photos you can see the central area surrounding Ashley Pond, and the pond is the only original landmark left in modern day Los Alamos.  Los Alamos 1940’s – Notice the roads are paved, so this photo was taken after the war. Ashley Pond seen in lower right. Photo courtesy Army Corps of Engineers  Ashley Pond, Los Alamos 2019. Photo by author To help the reader understand the historical arc of Manhattan Project I created a high level timeline, with a bare minimum of nuclear equations, to summarize the remarkable nuclear physics and chemistry discoveries from 1938 to 1945 time period. Keep in mind that the movie begins in September 1942: Key Discoveries in Nuclear Physics Preceding and During the Manhattan Project By: Ben Clark, February 10, 2020 Part 1 – Nuclear Fission Discover December 1938 Otto Hahn and Fritz Strassmann at Kaiser Wilhelm Institute, after working for years firing neutrons at uranium, realize that neutrons fired into uranium do not just produce an isotope or transuranic element, but that they also split the uranium nucleus (fission) creating elements much lower in the periodic table. There had been signs of this for a long time, but everyone had rejected it as impossible. The discovery of fission by Hahn and Strassmann rocked the physics community to its core. The fact that fission was discovered in Nazi ruled Munich yet the two top scientists were permitted to publish their discovery was a godsend for scientific endeavors outside of Germany. Question: What if the Nazis had classified the fission discovery as Top Secret? Would the Allied powers have invested so much talent and money on the urgent development of an atomic bomb? It is unlikely this question will ever be answered.  Cartoon of nuclear fission discovered by German scientists January 1939 - Otto Frisch at Birmingham Lab, UK conducts an experiment confirming Hahn and Strassmann’s fission results, and calculates the energy released follows Einstein’s Law: E = mc2. February 1939 - Bohr at Princeton Lab discovers that slow neutron (velocity< 2200 m/sec) fission in uranium is happening only in the uranium 235 isotope, not in the uranium 238 (raw uranium ore, or yellow cake, contains 99.3% U238 and 0.7% U235). The nuclear physics community becomes focused on the slow neutron fission because that is where U235 is so different from U238. The idea of isotope separation and concentration of U235 becomes of major focus of the Nuclear Chemists. There is no difference in the chemistry of the two isotopes. Some scientists still assume that isotope separation is impossible. March 1939 - Szilard/Zinn repeated the German fission experiments at Columbia, UK and discovered 2 or 3 neutrons being emitted in each fission process; thereby, providing excess neutrons for a chain reaction. This key discovery is reported to the U.S. Government, but the early contacts with the US feds don’t lead to any serious action. August 1939 - The United States government became aware of the German nuclear program in August 1939, when Albert Einstein wrote to President Roosevelt, warning "that it may become possible to set up a nuclear chain reaction in a large mass of uranium by which vast amounts of power and large quantities of new radium-like elements would be generated." Einstein also mentions the fact the Germans had seized the Czech uranium mines. A year later the Germans seize 2100 metric tons of uranium ore from Belgium. September 01, 1939 - Germany invades Poland and WW2 begins. January 1940 - Sir Henry Tizard, head of British wartime scientific research, sets up the top secret “Maud” committee to investigate possibilities of building an atomic bomb. Working in conjunction with the MAUD project, Franz Simon and his team of scientists successfully separate U235 from yellowcake using a complex and very expensive mass separation technique named the gaseous diffusion process. February-March 1940 - Otto Frisch and Rudolf Peierls working at University of Birmingham, UK focus on the fission process operating on a tiny sample of purified U235, a combination that no one had considered before mainly because of the unavailability of purified U235 until the MAUD project. Their results set the parameters for the design of an atomic weapon. The physicists had to answer two fundamental questions: How much fissile material would be required for the weapons and how much time would be needed for an effective detonation? Frisch writes, “To my amazement the amount [of material required for a bomb] was very much smaller than I had expected; it was not a matter of tons, but something like pounds.” They calculated that 80 neutron generations, taking a total of 320 millionths of a second (at four millionths of a second per generation), which would still be fast enough to precede the expansion of the bomb material and the disassembly of the super-critical mass. The Frisch/Peierls results taken together with the success of gaseous diffusion for separating U235 from natural uranium, Frisch writes, “We came to the conclusion that an atomic bomb might, after all, be possible.” Part 2 – Discovery of Plutonium Element 94 June 1940 - Vannevar Bush, electrical engineer, former administrator at MIT and head of Carnegie Institute, persuades FDR to let him start the National Defense Research Council (NDRC) to coordinate all scientific research for the US military. Bush named head of NDRC and reports directly to President FDR. February 1941 - Plutonium (Pu239) was discovered by Glenn Seaborg and his team at Berkeley Lab. Using the cyclotron at the radiation lab, the team bombards uranium metal with bursts of deuteron (H2 a heavy isotope of hydrogen) atoms. The Plutonium is produced in sufficient amounts to be isolated by chemical separation from Uranium. Seaborg writes, “Thus it is now clear that our alpha activity is due to the new element with the atomic number 94.” The US was not yet at war, but the discovery was kept top secret. March 1941 - Seaborg’s team makes another remarkable discovery. They isolated a small amount of pure Pu239 and fire slow neutrons at the sample. They record strong indications of fission – even stronger than from U235. He saw that a fissile Pu239 element, bred as a by-product in a uranium reactor, could be chemically separated using a process that was relatively easy and inexpensive as compared to the mass separation process needed for U235 (gaseous diffusion, thermal diffusion and electromagnetic). July 1941 - American scientists are briefed on the British Maud project. US and England agree to joint cooperation on nuclear physics. October 1941 - Roosevelt gives V. Bush authority to spend whatever is necessary to find if an atomic bomb can be built. Godfrey Hodgson writes in The Colonel, The Life and Wars of Henry Stimson: “The decision to build not only a bomb but the vast secret bureaucracy that would be required to create it [a bomb], was taken by the President alone.” Congress, judiciary, and cabinet knew nothing about it. This was one of the decisive moments in American history when the imperatives of world war tilted power toward the executive. December 7, 1941 - Japanese make surprise attack at Pearl Harbor, Hawaii. The USA enters WW2 as war is declared on Japan and Germany declares war on America. Early 1942 - Arthur Compton, Nobel Prize winner (1927) and Director of the Chicago Met Lab, chairs a meeting at Columbia and lays down this timetable: By July 1, 1942, determine whether a chain reaction was possible. By January 1943, to achieve the first controlled chain reaction in a reactor. By January 1944, to extract weapons grade U235 from uranium ore. By January 1945, construct the first atomic bomb. Compton stressed that since Germany had at least a two year head start in nuclear physics applied to weapons research, the Allies were in a race with Germany to build the first atomic bomb. After the war, Compton wrote, “Our project became to us more vital than life or death.” The Manhattan Project – A Timeline of Key Events The movie starts here in September 1942 The highlights listed below are included in the movie and are well presented on screen. I included a few off-camera events separately for some clarification of the overall atomic bomb project. September 1942 - Colonel Leslie R. Groves was promoted to Brigadier General and appointed Director of the Manhattan Engineer District, the secret project to build the world’s first atomic bomb. His proven record of managing complex undertakings made him a logical choice to lead the most ambitious project in American history. Groves would lead both the military and civilian staff, and be in overall charge of security.  Paul Newman as Gen. Leslie Groves. Groves always wore his West Point graduation ring. Photo courtesy of imdb October 1942 - Groves meets with Robert Oppenheimer, the University of California, Berkeley physicist, and discuss the creation of a laboratory where the bomb could be designed and tested. Groves was impressed with the breadth of Oppenheimer's knowledge. A long conversation on a train in October 1942 convinced Groves and his top deputy, Kenneth Nichols that Oppenheimer thoroughly understood the issues involved in setting up a laboratory in a remote area. These were features that Groves found lacking in other foggy headed scientists, and he knew that broad knowledge would be vital in an interdisciplinary project that would involve not just physics, but chemistry, metallurgy, ordnance, and engineering. Groves became convinced that Oppenheimer was the best and only man to run the laboratory. The FBI objected to Oppenheimer’s connections with the US communist party, but Groves personally waived the security risks and issued a Top Secret Security clearance for Oppenheimer. October 1942 - Groves and Oppenheimer inspected sites in New Mexico, where they selected a suitable location for the laboratory at Los Alamos. Soon afterwards 54,000 acres of surrounding forest and grazing land was acquired by the US govt. Construction begins. The mission of the Los Alamos Lab is to design and build the bomb. The fissile materials would be produced in Oak Ridge, TN and Hanford, WA. April 1943 - Los Alamos Lab is staffed and begins work on bomb design. August 1943 - First live test of the Los Alamos “gun-type” fission bomb, using a dummy warhead, is dropped from a bomber. Field Tests of the design is so successful that the Los Alamos team has high confidence the weapon would work using U235 without a live field test.  “Little Boy” design - U235 two-part warhead shown in red, propellant in orange January 1944 - A new department is created at Los Alamos to study implosion type bomb design. Initial tests fail due to imprecise spherical detonations. Oppenheimer staffs up the Implosion design group and fires the original group leader, Edward Teller. April - June 1944 - The Los Alamos Lab received the first sample of reactor-produced plutonium from Oak Ridge. Los Alamos scientist Emilio Segre, working with this small sample of plutonium, was able to determine that reactor-bred plutonium had a higher concentration of the isotope plutonium-240 than cyclotron-produced plutonium. Since plutonium-240 has a high spontaneous fission rate, the increased number of spontaneous neutrons meant that nuclear pre-detonation, or “fizzle”, would be the likely result of the original gun-type bomb design, code-named “Thin Man”. It was abandoned for plutonium bombs, but still suitable for U235 bombs. This discovery meant that the entire plutonium weapon design effort at Los Alamos had to be altered to a more complicated implosion device, code-named “Fat Man.” The implosion design would use a series of explosive lenses to compress a solid sphere of plutonium-239 into a high-density core, initiating a nuclear chain reaction. Before physicists at Los Alamos could test the implosion design, they needed more plutonium for experiments. July 1944 - Oppenheimer reveals Segrè's final measurements to the Los Alamos staff, and orders the design of a reliable implosion design (Fat Man) to become the new top priority of the laboratory. The building of U235 gun-type weapon (Little Boy) continues to design freeze. December 1944 - After months of failures, the first successful explosive lens test at Los Alamos establishes feasibility of building an implosion bomb (Fat Man). 
 Hanford B reactor complex build in only 11 months by DuPont Company
April 1945 -- General Groves receives the Alsos report and discovers that the German nuclear program is not a threat. The German nuclear science progress had stalled out for lack of priority. The top German scientists were only doing lab scale research projects with no real plans for developing a weapon. This, of course, is good news, but there is an interesting scene in the movie where Groves hesitates to share the Alsos Intel with the Los Alamos staff. The threat of a German A-bomb was a great motivator for his scientists especially since many were American Jews (Oppenheimer, for one) and European Jewish refugees who had an axe to grind with the brutal, anti-Jewish Nazis. This dilemma is well presented in the movie. In real life, at least one Los Alamos scientist that I know of resigned after Germany surrendered. May 1945 - Little Boy is ready for combat use, except for the U235 warhead. Germany surrenders to allies. V-E Day May 7. Movie has a fun celebration scene. June 1945 - Target Committee meets and submits a list of Japanese cities. As depicted in the movie, both Oppenheimer and Groves attend the meeting. Approval is granted for Los Alamos to field test the Fat Man bomb design with a critical mass of plutonium 239.The meeting is well presented in the film, and one of the best scenes. July 16, 1945 - The nuclear bomb test is code named “Trinity”. A remote site is selected at Alamogordo, NM (about 250 miles south of Los Alamos). The “Trinity” nuclear test is 100% successful. Oppenheimer makes triumphant return to the Los Alamos Lab. End of the movie.
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