The Making of the Atomic Bomb

The Making of the Atomic Bomb by Richard Rhodes is a work of nonfiction chronicling the scientists, discoveries and other events surrounding the first nuclear fission weapons.

The first part of the book discusses the web of relationships and discoveries that occurred from around the turn of the century to beginning of World War 2. The discoveries and people varied from Leo Szilard and his idea of a chain reaction, Bohr and his model of the atom and insight that atomic number should decide periodic table location, Otto Hahn and Lise Meitner and the Kaiser Wilhelm Institutes, Chaim Weizemann and Cordite, transmutation, the Mass Spectrograph, the Cyclotron, Neutrons, the difference between slow and fast Neutrons and many more discoveries, inventions and scientists. Then the book discusses how this web of relationships was able to evacuate scientists from Germany, Italy and Russia, who were or had Jewish family. In addition to simple evacuation, the Physicists outside of Germany, Italy and Russia were able locate jobs relatively quickly for the émigrés.

The second part of the book discusses the formation of the Manhattan Project itself, and touches on the developments in Germany and Japan.

Allies

The allied program was mainly a program by the US and UK. Russia was left out initially due to the migration of most scientists to the US and UK before and after Germany instituted anti-Jewish laws that prohibited Jewish civil servants. The US took the brunt of the research willingly as the UK was on the battlefront and needed technologies that could be implemented immediately, and that would not require as great of resources as an atomic program would. Towards the end of the war, however, the atomic program was kept secret from Russia via conscious decisions by Churchill and FDR. This was despite the objections by Bohr and others that doing so would create mistrust over a technology that Russia could attain rather quickly, once aware that it existed.

In the beginning the program was nothing more than individual physicists discovering interesting things about atoms, and publishing them. Leo Szilard realized how dangerous this would be if they discovered road markers on the path to an atomic weapon, published them, and Nazi Germany’s atomic program benefited. He went on a mission to get the scientists to hold a code of secrecy and submit research to the US government for safekeeping and support. Initially it wasn’t very successful in trying to reign in scientists who tended towards a free information exchange, but with the influence of other scientists who saw the real possibility of an atomic weapon, secrecy began. With the help of Einstein the group of physicists was able to alert Washington to the very real possibility of such a weapon and of its probable development by Germany. Washington responded by organizing the Advisory Committee on Uranium which was to take its ultimate form as the Manhattan Project after varied evolutions. The Manhattan Project was the secret and full scale development of the atomic weapons. It involved various locations of scientist (the main location being at Los Alamos, New Mexico) and two main factories in Oak Ridge, Tennessee, and Hanford, Washington, both of which were extraordinary undertakings to build from ground up.

The Atomic project quickly developed theories and experimental evidence about the use of Tubealloy (codename for generic Uranium), Magnesium (Codename for Uranium 235) and Copper (codename for Plutonium). It developed the egg-boiling experiment (codename for developments of a self sustained reaction in an uranium pile) into fruition with the first self sustained chain reaction observed by Fermi’s team December 2 1942.

Development of isotope separation technologies was greatly influenced by the threat of a German Atomic project, and thus economics was much secondary. To this effect a policy of parallel development occurred with five different technologies being built: a centrifuge plant, gaseous barrier diffusion plant, electromagnetic separation plant, graphite piles and heavy water piles. Ultimately they were used in conjunction with each other to maximize efficiency.

Another important aspect was Gadget development. Gadget was the term used for the bomb designs themselves. Initially two were selected as most promising, a canon-bomb (where critical mass of Uranium was completed by shooting the missing part into a sphere, triggering an explosion) and an implosion design (which had a hollow sphere of uranium crushed into a solid sphere by explosives creating a critical mass). The canon-bomb initially called the Tall Man (a reference to FDR) eventually developed into the Little Boy when new understandings allowed them to reduce the length of the cannon. The implosion design, called the Fat Man (a reference to Churchill) was the most technically problematic of the two designs, and required cutting edge technologies like an IBM computer, explosive lenses (focused and directed explosions) and the development of calculations for hydrodynamics of an implosion.

By March 3 1944 the program was in such full swing that the first atomic bomb drops were practiced by B29s at Muroc Army Air Force Base in California in order to test for needed modifications to the aircraft. This evolved in September into Paul Tibbets’ command of the project codenamed “Silverplate.” “Silverplate” was the creation of the 509^th Composite Group whose mission, unknown to even them, was to deliver the atomic bomb.

Germany

Though the prospect of Germany having an atomic bomb program was the reason that the US and UK were pursuing their own programs, there was no active intelligence program to discover the progress of a German program until the end of the war.

The German program was stifled by many problems and setbacks. Perhaps the first was the reduced number of atomic physicists, due to the Jewish laws that encouraged many Jewish Physicists to escape to the UK and US. Another was the miscalculations ruling out carbon as a moderator for a chain reaction. (Carbon was a cheaper alternative to heavy water). Without a cheap moderator the German fission program was tied to an expensive and rare resource that came from one factory in the world in Vemork, Norway. This factory was attacked several times during the war, limiting the ability of German Physicists even more.

Circa 1942, the Germans scuttled their Atomic Bomb project, as they expected a bomb to not be developed in time for the current war, and with a scarcity of resources they decided to use their resources to develop weapons that might impact the war. They did however continue their research into fission reactors as power sources to move vehicles. Ultimately at the end of the war in Europe, German physicists had just created a test reactor that Heisenberg estimated if increased by 50% in size would create a self sustaining chain reaction.

Japan

Unlike the civilian origins of the atomic programs in the UK, US and Germany, the Japanese project originated in the military via a report requested by and prepared for the director of the Aviation Technology Research Institute of the Imperial Japanese Army. In 1941, Tokutaro Hagiwara was the first to suggest a hydrogen bomb ignited by an atomic weapon. Between 1942 and 1943, the Japanese Navy convened a committee to decide whether or not to pursue atomic bomb research. During this investigation, the Navy decided to encourage the development of other technologies as an atomic bomb seemed unreachable during the war, by any of the parties. (For Japan, it would require “a tenth of the annual Japanese electrical capacity and half of the nation’s copper output” in addition to approximately ten years and finding enough uranium in the first place). At the same time, research into a fission reactor was encouraged by the Navy. Also at this time, then University of Kyoto, where Tokutaro Hagiwara taught, received funding for atomic bomb development by the Fleet Administration Center of the Navy.

Despite the Navy withdrawing from major support of an atomic weapon, the Army continued to do so. But was plagued by misunderstandings such as: Army Liason: “If uranium is to be used as an explosive, 10 kg is required. Why not use 10 kg of a conventional explosive?” Scientist: “That’s nonsense.” (pp. 582)

Ultimately the bulk of the Japanese atomic bomb project went up in flames, due to firebombing by America B-29s, which caught the wooden building which housed the gaseous thermal diffusion equipment (Japan’s method of U235 extraction) on fire.

The Making of the Atomic Bomb is packed with stories that attempt to bring life to the characters, times and events that surrounded the development of the first nuclear weapons.