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DOE OSTI · 1814876

When the Moon had a magnetosphere

Green, James·Draper, David·Boardsen, Scott·Dong, Chaunfei
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Abstract

Apollo lunar samples reveal that the Moon generated its own global magnetosphere, lasting from ~4.25 to ~2.5 billion years (Ga) ago. At peak lunar magnetic intensity (4 Ga ago), the Moon was volcanically active, likely generating a very tenuous atmosphere, and, it is believed, was at a geocentric distance of ~18 Earth radii (R E ). Solar storms strip a planet’s atmosphere over time, and only a strong magnetosphere would be able to provide maximum protection. We present simplified magnetic dipole field modeling confined within a paraboloidal-shaped magnetopause to show how the expected Earth-Moon coupled magnetospheres provide a substantial buffer from the expected intense solar wind, reducing Earth’s atmospheric loss to space.

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Green, James, Draper, David, Boardsen, Scott, Dong, Chaunfei. 2020-10-14. When the Moon had a magnetosphere. https://doi.org/10.1126/sciadv.abc0865

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