1. THE AGE OF THE
ATOM
Essential Questions:
What was the Manhattan Project?
1.
What was the Potsdam Declaration?
2.
How did events of the bombing of Hiroshima
3.
and Nagasaki occur?
When and how did the Second World War end?
4.
2. Manhattan Project
Project to develop first nuclear weapon
during WWII
Involved United States, United Kingdom,
and Canada
Under control of the U.S. Army Corps of
Engineers
Scientific research was directed by
American J. Robert Oppenheimer
Since 1930s officials feared Nazi Germany
was also investigating nuclear weapons
The Project eventually employed more
than 130,000 people and cost nearly $2
billion dollars ($24 billion in 2008 dollars)
3. Potsdam Declaration
July 26, Truman and the allied
leaders issue The Potsdam
Declaration
Outlined terms of surrender for Japan
Presented as an ultimatum and
stated that without a surrender, the
Allies would attack Japan
The atomic bomb was not mentioned
On July 28, Japan rejected the
ultimatum
Truman now had to make the biggest
decision of the war: whether to use
the bomb
In the end, Truman made the
decision to drop the atomic bombs on
Japan:
Bring about a quick resolution of the
war
4. Hiroshima
Hiroshima was the primary target of the
first mission on August 6, 1945
B-29 Enola Gay, was piloted by Colonel
Paul Tibbets
Enola Gay was named after Tibbets'
mother
Little Boy (the bomb) was released at
8:15am
Took fifty-seven seconds to fall from
the aircraft
It detonated 1,900 feet above the city
The radius of total destruction was one
mile, with fires across 4 square miles
70,000 to 80,000 people, or about 30% of
the population, were killed immediately
The residents of Hiroshima were given no
notice of the atomic bomb
5. Nagasaki
August 9, 1945; B-29 Bockscar was
launched
Its primary target was Kokura; Nagasaki
was the secondary target
Bockscar arrived at the rendezvous and
the two other B-29s it was to meet weren’t
there
Bockscar circled for 40 minutes and
finally flew on alone
By the time they reached Kokura a half
hour later, a 70% cloud cover obscured the
city
Prevented visual attack required by
orders
They moved on to Nagasaki
At 11:01am, Bockscar visually sighted the
6. There were more…
The United States expected to
have another atomic bomb ready
for use in the third week of
August
Three more were scheduled to
be ready by September
A further three were to be ready
in October
There was already discussion in
the War Department about
conserving the bombs (and
future bombs) in production until
Operation Downfall
The codename given to the
projected invasion of Japan
7. The Aftermath
Immediate effects of the blast
at Hiroshima killed
approximately 70,000 people
Estimates of total deaths by
the end of 1945 from burns,
radiation, and disease, range
from 90,000 to 140,000
Others died of long term
effects from the blast, such as
cancer
Some estimates state up to
200,000 had died by 1950
due to cancer
8. Japan Surrenders
August 15, 1945, Japanese Emperor
Hirohito announced Japan would accept
the Potsdam terms
Was broadcast to the Japanese people
over the radio
The Emperor then advised the Allies via
the Swiss diplomatic mission in
Washington, D.C.
The formal Japanese signing of the
surrender took place on board the
battleship USS Missouri in Tokyo Bay
Japan was the last Axis Power to
surrender
V-J Day marked the official end of the war
in the Pacific
The Second World War was over
