scientists.
Nonetheless, by 1944 sufficient progress had been made to
persuade the scientists that their efforts might succeed.
A test of the
plutonium implosion device was necessary to determine if it would work and
what its effects would be.
Led by Dr. J. Robert Oppenheimer, Manhattan
Project scientists at Los Alamos Laboratory (later to become the Los Alamos
National Laboratory) were "to make preparations for a field test in which
blast, earth shock, neutron and gamma radiation would be studied and complete
photographic records made of the explosion and any atmospheric phenomena
connected with the explosion" (1: 13,14).
The planned firing date for the TRINITY device was originally 4 July
1945.
On 14 June 1945, Dr. Oppenheimer changed the test date to no earlier
than 13 July and no later than 23 July.
On 30 June, the earliest firing date
was moved to 16 July, even though better weather was forecast for 18 and 19
July.
The TRINITY test organization adjusted the schedule because the Allied
conference in Potsdam, Germany, was about to begin and the President needed
the results of the test as soon as possible (1: 26).
‘
On 6 August 1945, 3 weeks after the detonation of TRINITY, the first
uranium-fueled nuclear bomb, a gun-type weapon code named LITTLE BOY, was
detonated over Hiroshima.
On 9 August, FAT MAN, a plutonium-fueled implosion
weapon with the same design as the TRINITY device, was detonated over another
Japanese city, Nagasaki.
Two days later, the Japanese Government informed the
United States of its decision to surrender.
On 2 September 1945, Japan
officially surrendered to the Allied Governments, thereby bringing World War
II to an end (1: 11).
4.1.2
TRINITY Test Operations.
From 16 July 1945 through 1946, about 1,000 military and civilian
personnel took part in Project TRINITY or visited the test site.
All
participants, civilian as well as military, were under the authority of the
MED.
Project activities included scientific studies.
Military exercises were
not conducted at TRINITY (1: 1).
The Los Alamos Laboratory, which was staffed and administered by the
University of California (under contract to the MED), conducted diagnostic
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