Biogenic Oxygen on the Moon Could Hold Secrets to Earth's Past: Lunar orbiting data show that terrestrial oxygen rains down periodically on the Moon, enticing researchers with an opportunity to study Earth's ancient atmosphere.

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Biogenic Oxygen on the Moon Could Hold Secrets to Earth's Past: Lunar orbiting data show that terrestrial oxygen rains down periodically on the Moon, enticing researchers with an opportunity to study Earth's ancient atmosphere.