Saturday, February 13, 2010

The Nuclear Age

The late 1800’s and early 1900’s were an exciting time in the world of science. Many long-standing beliefs were shattered and the knowledge gained by scientists went up tremendously. New theories and new discoveries were constantly pushing the boundaries of science and a whole collective of contemporary scientists were behind this. The discoveries and theories which had been worked on were perfected and brought to light in 1945 when the atomic bomb was perfected and two atomic bombs were detonated over Japan. The work of creating the atomic bomb was the result of years of scientific work in a perfect marriage with political forces.

Isaac Newton’s theories were for hundreds of years held as dogma in the world of physics. In 1896 one discovery which helped lead to the atomic bomb and a complete change in the direction of physics was made by Henri Becquerel when he accidentally discovered radioactivity which he found while working with uranium. At the time awareness what constituted the makeup of an atom would make huge strides in 1897 when the electron was discovered by J.J. Thomson. In 1905 relatively unknown Albert Einstein published his theory of relativity which led to major changes in the outlook of the science world with the new understanding of the relationship between matter and energy. This theory changed the course of physics at a time when it was thought by most scientists that most critical areas of knowledge were already known and there was just a few more areas of knowledge on which to expand. Other key discoveries were soon to come including in 1911 when Ernest Rutherford discovered the nucleus of the atom. In 1913 Niels Bohr published the theory of atomic structure which described electrons orbiting the nucleus of an atom. In 1919 Ernest Rutherford became the first person ever to artificially create a nuclear reaction when he changed nitrogen into oxygen. In 1920 Rutherford would first issue the idea of the neutron which was later proven to exist in 1932 by James Chadwick. The neutron being proved to exist was the final puzzle in knowing the atom. In 1929 American Ernest Lawrence created the cyclotron which sped up how protons could be hurled at atomic nuclei; this tool would be of major use during later nuclear experiments. In the same year of 1932, John Cockroft and Ernest Walton became the first to split the atom. In 1934 Italian scientist Enrico Fermi irradiated uranium with neutrons and thought he had found new transuranic elements. In reality what Fermi had done was produce the world’s first nuclear fission and provide further proof of Einstein’s theory of relativity of the relationship between matter and energy, but no knew that until later when in 1938 German scientists Otto Hahn and Fritz Strassman conducted a similar experiment and sent their results to Lise Meltner who confirmed nuclear fission. Nuclear fission had the capacity to unleash large amounts of energy and for the world political scene in 1939 which was a world that was on the brink of war, these developments held major possibilities for military power.
Germany in the early 1900’s was a hotbed of scientific activity. Several of the top scientists in the world at the time were of German origin or lived in Germany including Leo Szilard, Albert Einstein, Klaus Fuchs and other top scientists. Germany was also a pioneer in coordinating scientific work along with military work. German scientists developed several chemicals in a well coordinated effort during World War 1. Many of the top German scientists though were Jews, and Germany was a hotbed of anti-Semitic thought. The anti-Semitic sentiments in Germany would reach a crescendo in 1933 when Adolf Hitler and the Nazis rose to power in Germany. Persecution was soon to follow for Jews and several top Jewish scientists would leave the country after the Nazis took power. Hitler in his first years in power took steps to rearm Germany and prepare Germany for war. In 1939 work started on a German project to build an atomic weapon. In that same year Jewish scientists Albert Einstein and Leo Szilard sent a letter to American President Franklin Roosevelt advising him of the German work to build a nuclear weapon, and advised him to start working on such a project. This would eventually be the catalyst for the top secret Manhattan Project.

In 1939 Europe when Germany invaded Poland, Europe erupted into the Second World War. This war which also raged across the Pacific was the first war to feature wide scale bombing of cities and featured the heaviest use of aircraft in any war up to that time. The United States was not in the war at the time but was a strong backer of Great Britain in the war, who were making plans on building a nuclear weapon of their own. As a result of the letter of Szilard and Einstein, American President Franklin Roosevelt created a uranium committee to conduct experiments of uranium. This committee would recommend government funding of isotope separation research as well as funding research Fermi and Szilard were doing at Columbia University on nuclear chain reactions. In 1940 in Britain, Otto Frisch and Rudolf Peierls created a memorandum that for the first time had a theoretical viewpoint of how an atomic bomb would work with the use of uranium 235. This memorandum also suggested that the bomb could be used similarly to the other bombs which were of use at the time. In 1940 plutonium was also produced for the first time ever which would be a key component in the first nuclear bomb.

In 1941 things would kick into overdrive for the effort to build a nuclear weapon. On December 6, 1941 President Roosevelt authorized the creation of the Manhattan Engineering District later to be known as the Manhattan Project. The next day on December 7, 1941 Japan attacked Pearl Harbor and the United States was officially drawn into World War II. On December 11, 1941 Germany declared war on the United States. The United States and Great Britain would become Allies not just on the battlefield but also in sharing scientific information. Scientific work in the U.S. continued on atomic research in 1942 at different sites but without a central leadership until September of 1942 when Leslie Groves was put in charge of the Manhattan Engineering District now called the Manhattan Project. The Manhattan Project was now placed under the control of the U.S. Army. The goal of the project was now to speed up process in creating a bomb as soon as possible to be used in World War II. The hope was to have a bomb ready for use by 1945. J. Robert Oppenheimer was appointed as scientific director of the project. The project was then to be headquartered from Los Alamos, New Mexico with most of the work in to building the actual bomb conducted from there as well as sites located in other parts of the country. During that same year of 1942, Enrico Fermi and Leo Szilard who had been working on a nuclear pile in Chicago, managed successfully complete the world’s first working nuclear reactor. The pile technology would be later used as the prototype for the first regular nuclear reactor in Hanford, Washington in order to produce plutonium. At the same time the decision was made to heavily expand uranium production which would be headquartered in Oak Ridge, Tennessee. In July 1943 experiments would begin at Los Alamos and shortly after Niels Bohr and Enrico Fermi would also become added to the Los Alamos team.

In 1944-45 things were moving fast on both the war front and the Manhattan Project. The German army was now taking heavy losses and many German cities and research facilities were becoming lost by Allied bombs. But, the United States suffered a huge blow in April 1945 when President Franklin Roosevelt died. Vice President Harry Truman became president and found out about the Manhattan Project which was so top secret that even he had no knowledge of it. In May 1945 Germany would surrender and end the European theater of World War II. The war picture was now focused solely on Japan in the Pacific Theater. The United States had taken an island by island approach in the war with Japan that proved to be effective but at the same time had cost many American lives. The only thing left for the U.S. to win the war was a full scale invasion of Japan that was estimated to cost perhaps one million American lives. At this same time the atomic bomb was coming to fruition and the bomb was ready to be tested. The decision had been made in 1944 that the bomb would work best as an implosion device and to solely focus on using a plutonium bomb rather than uranium. The feeling was that a uranium based bomb was so sure to work that it was better to focus on the more difficult plutonium bomb. The plutonium bomb was designed to use explosives to bring the nuclear core to criticality. There were a wide range of predictions leading up to the days of the eventual testing of the bomb, among them fears that a nuclear explosion could ignite the atmosphere. On July 16, 1945 the time was finally right for a nuclear weapon to be tested. The test was a complete success and the bomb exploded had an explosive force of 18.6 kilotons. The nuclear weapon and all the research that Szilard, Bohr, Fermi and several others had worked on for the past years had finally come to fruition and a nuclear weapon was finally ready to be used in warfare against other human beings.
The atomic weapons created by scientists were a tremendous success. Their use in war led to the deaths of hundreds of thousands of people and leveled two Japanese cities. But, the success of the weapons showed how scientists could build on the work of earlier scientists and lead to fantastic results. It also showed that with science working hand in hand with the government the possibilities for science to reach were endless.

References
Rhodes, Richard. The Making of the Atomic Bomb. Simon & Schuster Paperbacks, 1986.
http://www.3rd1000.com [cited December 12, 2009] Available at http://www.3rd1000.com/nuclear/cruc18.htm
http://www.atomicarchive.com [cited December 12, 2009] Available at http://www.atomicarchive.com/Timeline/Timeline.shtml
http://www.atomicarchive.com [cited December 12, 2009] Available at http://www.atomicarchive.com/History/mp/index.shtml

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