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politics1953

1953 U.S. nuclear test

April 25, 1953

The Simon test produced unexpected radioactive fallout that contaminated New York's Capital District and was suppressed by the AEC for decades.

Quick Facts

Year
1953
Category
politics

Key Facts

Test date
25 April 1953, 04:30 local time
Yield
43 kilotons
Detonation height
300 feet (91 m tower)
Fallout impact area
Washington and Rensselaer counties, New York
Radiation anomaly
Hundreds of thousands of times above normal
Disclosure agent
Congressman Samuel S. Stratton

By the Numbers

25
Test date
43kilotons
Yield
300feet (91 m tower)
Detonation height

Location

Map of Mercury, United StatesMap of Mercury, United StatesMercury, United States

Cause → Event → Consequence

Cause

As part of Operation Upshot–Knothole, the United States detonated the Simon device to test the TX-17/24 thermonuclear weapon design at the Nevada Test Site. The mushroom cloud's radioactive material failed to disperse normally, remaining concentrated as it drifted eastward across the country over several days.

Event

On 25 April 1953, a 43-kiloton nuclear device was detonated on a 300-foot tower at Nevada Test Site Area 1. The radioactive cloud traveled east and, days later, was swept into a severe thunderstorm over New York's Capital District, depositing concentrated fallout primarily over Washington and Rensselaer counties.

Consequence

Students at Rensselaer Polytechnic Institute in Troy, New York detected radiation levels hundreds of thousands of times above normal. Professor Herbert Clark reported findings to the Atomic Energy Commission, which dismissed and then suppressed the information under threat of arrest for treason. The incident remained concealed for decades until Congressman Samuel S. Stratton exposed it.

Timeline Context

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