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USGS · 70021905

Estimated solar wind-implanted helium-3 distribution on the Moon

J. R. Johnson·T. D. Swindle·P. G. Lucey
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Abstract

Among the solar wind-implanted volatiles present in the lunar regolith, ³He is possibly the most valuable resource because of its potential as a fusion fuel. The abundance of ³He in the lunar regolith at a given location depends on surface maturity, the amount of solar wind fluence, and titanium content, because ilmenite (FeTiO 3 ) retains helium much better than other major lunar minerals. Surface maturity and TiO 2 maps from Clementine multispectral data sets are combined here with a solar wind fluence model to produce a ³He abundance map of the Moon. Comparison of the predicted ³He values to landing site observations shows good correlation. The highest ³He abundances occur in the farside maria (due to greater solar wind fluence received) and in higher TiO 2 nearside mare regions.

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J. R. Johnson, T. D. Swindle, P. G. Lucey. 1999. Estimated solar wind-implanted helium-3 distribution on the Moon. https://doi.org/10.1029/1998gl900305

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