Earth's magnetic field has been sending Earth's air to the Moon for ages
Scientists just found out that Earth's magnetic field has been helping guide bits of our atmosphere—like water and nitrogen—all the way to the Moon for billions of years.
They figured this out by taking a fresh look at Apollo mission soil samples and realized these elements aren't just from solar wind; some actually come straight from Earth.
How does this happen?
When the Moon swings behind Earth into a zone called the magnetotail (think: Earth's magnetic "shadow"), particles from our upper atmosphere get swept up by magnetic field lines and land on the lunar surface.
Simulations show that today's Earth—with its strong magnetic field—matches what scientists found in those old Moon rocks best.
Why should you care?
Lunar soil basically holds a time capsule of Earth's ancient air.
This could help us understand our planet's past climate, give clues about life on Mars, or even guide future missions looking for water and other essentials on the Moon.