Earth's Ionosphere May Have Been Seeding the Moon With Water

Researchers at the University of Alaska Fairbanks Geophysical Institute suggest hydrogen and oxygen ions escaping Earth's ionosphere reach the Moon via the magnetotail and may bond into water in lunar soil. A 2022 study estimated up to 3,500 cubic kilometers of terrestrial-derived water-related material could have accumulated in lunar polar soil.

• The Moon spends about five days a month inside Earth's magnetotail
• Estimate: up to 3,500 cubic km of water-related material at the poles
• Model assumes roughly 1% of escaping material reaches the Moon
• Confirmation requires isotopic analysis of lunar soil samples