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Updated: Jul 12, 2026

06:14
Simulating Imaging of Large Scale Radio Arrays on the Lunar Surface
Published on: July 30, 2020
Radioactivity of the lunar surface
Summary
Radon and thoron gas diffusing from the Moon
Area of Science:
- Lunar science
- Radiochemistry
- Geophysics
Background:
- The lunar surface may accumulate radioactive elements.
- Radon and thoron are naturally occurring radioactive gases.
Purpose of the Study:
- To investigate the potential for a radioactive surface layer on the Moon.
- To estimate the equilibrium activity of this layer.
Main Methods:
- Modeling radon and thoron flux from the lunar surface.
- Comparing lunar flux to Earth's surface measurements.
Main Results:
- Lunar surface diffusion of radon and thoron can create a radioactive layer.
- Estimated equilibrium activity is approximately 1 microcurie per square meter.
- This activity emits alpha, beta, and gamma radiation.
Conclusions:
- The Moon's surface can become radioactive due to gas diffusion.
- The estimated activity level has implications for lunar exploration and sample analysis.
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