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Updated: Jun 21, 2026
10:29
Experimental Methodology for Estimation of Local Heat Fluxes and Burning Rates in Steady Laminar Boundary Layer Diffusion Flames
Published on: June 1, 2016
Summary
The 1966 SNAP-9A generator disintegration released plutonium-238 into the atmosphere. Analysis shows this plutonium-238 likely burned up and ablated into 10-millimicron particles during reentry.
Area of Science:
- Atmospheric chemistry
- Nuclear engineering
- Environmental science
Background:
- A 1966 event involved the disintegration of a Satellite Nuclear Auxiliary Power (SNAP-9A) generator.
- This event released plutonium-238 into the Earth's stratosphere.
- Understanding the fate of this released material is crucial for environmental and safety assessments.
Purpose of the Study:
- To determine the atmospheric fate of plutonium-238 released from the SNAP-9A generator.
- To analyze the particle size distribution of the reentry-ablated plutonium-238.
- To confirm the complete combustion and ablation hypothesis.
Main Methods:
- Analysis of stratospheric plutonium-238 inventory.
- Estimation of particle size distribution based on reentry physics.
- Comparison of estimated particle size with theoretical combustion models.
Main Results:
- The stratospheric plutonium-238 inventory is consistent with the total amount from the SNAP-9A generator.
- Evidence suggests complete burnup and ablation of pyrophoric plutonium-238 during reentry.
- The estimated arithmetic mean particle size was approximately 10 millimicrons.
Conclusions:
- The SNAP-9A generator's plutonium-238 completely burned up and ablated during atmospheric reentry.
- The resulting plutonium-238 particles are extremely small, with a mean size of 10 millimicrons.
- This finding supports the understanding of radioactive material dispersal following spaceborne generator failures.
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