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Clarification of Johnston Island Nuclear Tests
Kathleen M Thiessen1, Steven L Simon2
1Oak Ridge Center for Risk Analysis, Inc., 102 Donner Drive, Oak Ridge, TN 37830.
Health Physics
|April 28, 2025
Summary
US nuclear weapons testing at Johnston Island included 16 launches from 1958-1962. Four failed launches caused local contamination but are often excluded from official nuclear test lists.
Area of Science:
- Nuclear Science
- Environmental Science
- History of Science
Background:
- US nuclear weapons testing conducted at Johnston Island in 1958 and 1962.
- Official records of nuclear tests primarily include events with successful detonations.
- Previous summaries have inaccurately conflated failed launches with successful nuclear tests.
Purpose of the Study:
- To clarify the distinction between successful nuclear tests and failed launches at Johnston Island.
- To correct the misconception that all launches resulted in nuclear detonations.
- To provide an accurate record of all 16 nuclear device launches from Johnston Island.
Main Methods:
- Reviewing historical records of US nuclear weapons launches from Johnston Island.
- Analyzing data on successful launches with nuclear detonations.
- Identifying and documenting failed launches, including those causing local contamination.
Main Results:
- A total of 16 nuclear devices were launched from Johnston Island between 1958 and 1962.
- Twelve launches resulted in successful high-altitude nuclear detonations.
- Four launches failed, resulting in aborted tests, with three causing significant local contamination.
Conclusions:
- Failed launches without detonations are often omitted from official nuclear test lists.
- Three of the four failed launches at Johnston Island caused notable local contamination.
- Accurate documentation of all launches is crucial for understanding the full scope of nuclear activities and their environmental impact.
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