Trinity Test

Uses of Plutonium. The fissile isotope Pu had its first use in fission weapons, beginning with the Trinity test at Alamogordo, New Mexico, on July 16, 1945, followed soon thereafter by the "Litde Boy" bomb dropped on Nagasaki on August 9, 1945. Its weapons use was extended as triggers for thermonuclear weapons. This isotope is produced in and consumed as fuel in breeder reactors. The short-Hved isotope Tu has been used in radioisotope electrical generators in unmanned space sateUites, lunar and interplanetary spaceships, heart pacemakers, and (as Tu—Be alloy) neutron sources (23). 

The rest is history - history that transformed the twentieth century, history that divides one kind of world from another. Oppenheimer, Szilard, Bohr, Fermi, and the others knew that this was indeed the significance of their quest, and for the most part they were as exhilarated by the challenge as they were dismayed by the goal. At the Trinity test of July 1945, when the first nuclear bomb was exploded in the Nevada desert, Oppenheimer recalled words from the Hindu scripture Bhagavad Gita Now I am become death, the destroyer of worlds. To the US military, on the other hand, this was just a bomb - albeit one powerful enough to cow the Japanese emperor into submission and end the murderous war in the Pacific. 

The surprise of the morning was perhaps Marshall s idea for an opening to Moscow He raised the question whether it might be desirable to invite two prominent Russian scientists to witness the [Trinity] test. Groves must have winced after the years of secrecy, after the thousands of numb man-hours of security work, that would be a renunciation worthy of Bohr himself. 

Parsons prepared to show a motion picture of the Trinity test. The projector refused to start. Then it started abruptly and began chewing up leader. Parsons told the projectionist to shut the machine off and improvised. He described the shot in the Jornada del Muerto how far away the light had been seen, how far away the explosion had been heard, the effects of the blast wave, the formation of the mushroom cloud. He did not iden-... 

A Figure 21.17 The Trinity test for the atom bomb deveioped during Worid War ii. The first human-made nuclear explosion took place on July 16, 1945, on the Alamogordo test range in New Mexico. 

The Trinity test of the first atomic bomb in the desert near Alamogordo, NM. [Photo credit US Department of Energy.)... 

Trinity Test Site. Reprinted from Vincent C. Jones, Manhattan The Amy and the Atomic Bomb (Wadungton, D.C. U.S. Government Printing Office, 1985). 

The success of the Trinity test meant that a second type of atomic bomb could be readied for use against Japan. In addition to the uranium gun model, which was not tested prior to being used in combat, the plutonium implosion device detonated at Trinity now figured in American Far Eastern strategy. In the end Little Boy, the untested uranium bomb, was dropped first at Hiroshima on August 6, 1945, while the plutonium weapon Fat Man followed three days later at Nagasaki on August 9. 

Translation Groves thought the plutonium weapon would be as powerful as the uraniiun device and that the Trinity test could be seen as far away as 250 miles and the noise heard for fifty miles. Initial measurements taken at the Alamogordo site suggested a yield in excess of 5,000 tons of TNT. Truman went back to the bargaining table with a new card in his hand. 

Grove s report at great length with Churchill. The British prime minister was elated and said that he now understood why Truman had been so forceful with Stalin the previous day, especially in his opposition to Russian designs on Eastern Europe and Germany. Churchill then told Truman that the bomb could lead to Japanese surrender without an invasion and eliminate the necessity for Russian military help. He recormnended that the President continue to take a hard line with Stalin. Truman and his advisors shared Churchill s views. The success of the Trinity test stiffened Truman s resolve, and he refused to accede to Stalin s new demands for concessions in Turkey and the Mediterranean. 

See Ibid., pp. 668-78, for more on the Trinity test and the responses of those present. 

Groves sends Stimson a report on the Trinity test. 

Hansen, Wayne R., and John C. Rodgers. Radiological Simvey and Evaluation of Fallout Area from the Trinity Test Chupadera Mesa and White Sands Missile Range, New Mexico. Los Alamos National Laboratory, Los Alamos, N.M., 1985. LA 10256, MS UCll. 

Tessmer, Carl F., and Daniel Brown. Carcinoma of the Skin in Bovine Exposed to Radioactive Fallout. Journal of the American Medical Association 170 (1962) 210-14. [A report of an animal exposed to radioactive fallout on the range near Alamogordo in July 1945 following the detonation of the first atomic bomb at the Trinity test site.]... 

Highlights There are not many published examples of analysis of postdetonation debris. The reported results from the 1945 Trinity test show that information on the core and constituents of the device can be derived from advanced analytical techniques, with repercussions for nuclear forensics analysis. 

Michael Light, One Hundred Suns (2003). 006 Trinity test, 16 July 1945... 

ALAMOGORDO BOMBING AND GUNNERY RANGE, NEW MEXICO. See TRINITY TEST SITE. 

BIG BROTHER. While attending the Potsdam Conference in July 1945, U.S. president Harry S. Truman received a top-secret message signaling the successful test conducted at the Trinity Test Site on 16 July. The coded message read in part Doctor was just returned most enthusiastic and confident that the little boy is as husky as his big brother. Truman knew that little boy referred to Little Boy, the bomb that was to be dropped on Japan. He correctly deduced that big brother referred to Gadget, the device used in the Trinity test. 

GADGET. The first successful detonation of a nuclear device took place at 5 29 45 a.m. Mountain War Time, 16 July 1945, at the Trinity Test Site, New Mexico. The spherically shaped device, about six feet in diameter, weighed five tons but exploded with a blast of about 20,000 tons TNT-equivalent (20 kilotons). Scientists working on the Manhattan Project had named the device Gadget. It was an implosion device, with plutonium as the nuclear explosive. One similar in design, nicknamed Fat Man, would be dropped over Nagasaki, Japan, on 9 August 1945. See also BIG BROTHER LITTLE BOY. 

JUMBO. U.S. plans for the 1945 Trinity test of the implosion-type nuclear device called for two explosions. The first would be a conventional explosion involving TNT, which would implode a subcritical mass of plutonium. If the implosion worked as designed, a second explosion would occur within a fraction of a second when critical mass was attained and a chain reaction occurred. If the implosion failed to achieve the desired chain reaction, however, the blast of TNT would throw the plutonium into the air and over the countryside. Because plutonium was both precious and toxic, those designing the Trinity test wanted to safeguard against such a loss. The solution was Jumbo, designed to contain the force of the TNT blast and secure the plutonium in the event the intended chain reaction failed. 

Steel tower 800 feet from the zero point. The blast vaporized the tower, but Jumbo survived. Although damaged in some follow-on testing, Jumbo remains at the Trinity Test Site as a National Historical Landmark accessible to the public. 

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