Author: Dr. Tony Phillips
What is moondust made of? Almost half is silicon dioxide glass created by meteoroids hitting the moon. These impacts, which have been going on for billions of years, fuse topsoil into glass and shatter the same into tiny pieces. Moondust is also rich in iron, calcium and magnesium bound up in minerals such as olivine and pyroxene. It's nothing like gunpowder.
So why the smell? No one knows.
ISS astronaut Don Pettit, who has never been to the moon but has an interest in space smells, offers one possibility:
"Picture yourself in a desert on Earth," he says. "What do you smell? Nothing, until it rains. The air is suddenly filled with sweet, peaty odors." Water evaporating from the ground carries molecules to your nose that have been trapped in dry soil for months.
Maybe something similar happens on the moon.
NASA plans to send people back to the moon in 2018, and they'll stay much longer than Apollo astronauts did. The next generation will have more time and better tools to tackle the mystery.
We've only just begun to smell the moondust.
Read more: NASA Apollo Chronicles