Thursday 17 February 2011

AA-W1: The Manhattan Project

During 1939 WWII was raging across Europe and all of the warring nations were constantly working to be one step ahead of their enemies on the battle field and in the laboratories.  One major technological advance of the time was the possibility of the use of nuclear energy for energy and weaponry.  The allied forces (the US, UK, and their allies) were worried about Nazi Germany’s potential nuclear capabilities, and rightly so.  Operation Alsos was carried out by the allied forces to discover the nuclear capabilities of the Nazi Germans.  As a result of the investigation a group of top physicists, including Albert Einstein, concluded that the Germans were capable of creating a nuclear bomb.  The Manhattan Project was then catalyzed by a letter sent by this group of physicists to American President Franklin D. Roosevelt which alerted him to this astronomically important fact. After the letter was delivered in 1939 discussions began on launching a secret project that would eventually lead to the development of an atomic weapon.  The project started as a relatively small group of researchers and grew into a nation-wide effort that employed more than 130,000 people and cost the US government over two billion dollars.  The massive effort eventually yielded many important breakthroughs in the field of nuclear physics and ultimately atomic weaponry, and ended the second world war.

Work was done in nearly forty laboratories and factories across the United States, Canada and Great Briton.  The primary goal of the scientists and the main factor in the creation of a nuclear bomb was the creation of a substantial amount of enriched uranium (U-235) which is necessary to successfully sustain a nuclear chain reaction.  U-235 must be taken out of uranium ore that contains 99% U-238, which is essentially useless for the atomic bomb.  The gathering of the U-235 was made more difficult by the fact that it is so similar in structure and weight to U-238 that it could not be extracted by any chemical methods.  A form of mechanical method of extraction had to be developed.  The necessary mechanical processes were developed by professors at the University of California at Berkley and Colombia University.  The first of which is a magnetic separation of the two forms of uranium.  The second of which was a gas centrifuge which, by spinning the particles very rapidly, pulled the heavier U-238 away from the lighter U-235 using centrifugal force.  Much of the Uranium enrichment was done at the Oak Ridge, Tennessee plant.  After the correct amount of enriched uranium was gathered all that had to be done was the “splitting of the atom”, so to speak.
“Splitting the atom” is more formally known as nuclear fission.  Nuclear fission basically involves the splitting of the nucleus of an atom into smaller parts (ie. smaller nuclei).  The way this happens is a free neutron collides with the nucleus of a U-235 atom and after the neutron is absorbed the U-235 exists as a highly unstable U-236 for a fraction of a second.  This highly unstable U-236 then explodes in a very high energy process which releases a lot of light, heat, and other energy in the form of rapidly moving neutrons.  These neutrons then are able to collide with other U-235 atoms and thus the chain reaction has begun.  This chain reaction can occur inside of a device known as a reactor, which is capable of controlling and harnessing the energy released.  But in terms of the atomic bomb all of this energy is allowed to escape in the form of a massive, bright, hot, powerful explosion.

The first test of the atomic bomb was on July 16, 1945.  The code name for the bomb was “The Gadget”.   The bomb was detonated in the early morning, still dark skies of northern New Mexico.  The blast was so hot that the ground beneath the explosion turned to glass and it was so bright that people of a near by town said that the sun rose twice that morning and a blind girl saw it 120 miles away.  The sheer power of the test instilled many different emotions in the people present and gave rise to a major moral and ethical debate about the use of such technology.  One of the bomb’s creators Isidor Rabi felt that the bomb upset the balance of nature and that humankind had become a potential detriment to nature. Robert Oppenheimer had a much deeper and morbid thought upon the sight and quoted a fragment from the Bhagavad Gita. "I am become Death, the destroyer of worlds".
Roosevelt died suddenly on April 12, 1945 and Vice President Harry Truman took the oath of office and became The President of The United States of America.  In August of 1945 orders from the Oval Office were carried out and atomic bombs Little Boy and Fat Man were dropped in the Japanese cities Hiroshima and Nagasaki, respectively.  The explosions were catastrophic.  It is estimated that around 80,000 people were instantly vaporised and the winds that resulted from the massive explosion created fire storms.  After the explosions the pilots expressed feelings of regret about having to be the ones to actually perform the act of dropping the bombs.
The bombs proved to be real juggernauts in the effort to win the war, as the effects of the blasts still live on today.  The fallout and remaining radiation from the explosion has severely damaged all aspects of life in the effected areas.  Contaminated rain water is still causing leukaemia in many populations and in severe cases there have been birth defects and physical deformities.  There is still a massive moral and ethical debate about whether it was the right thing to drop the bombs.  Nuclear security is now a top priority of many governments of leading nations around the world.  
Works Cited
http://www.mrdowling.com/706-manhattanproject.html

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