Summary:
- The Moon has been absorbing small amounts of Earth's atmosphere for billions of years, according to new research.
- This process, called "atmospheric sputtering," occurs when atoms and molecules from Earth's upper atmosphere are knocked off by high-energy particles from the Sun and get pulled into the Moon's gravity.
- The Moon's absorption of Earth's atmosphere is a very slow process, but over time it has led to the buildup of certain elements on the lunar surface, which could provide clues about the history of our planet's atmosphere.