One problem with spacefaring is smell. You know, old fashioned smelling astronauts cramped in a tight space. That is – if you’re not inside. When you’re inside for some time, you’ll get used to it. That leads to other questions about smell. What does a nebula smell like? How does it smell on Saturn’s moon Titan, with all its methane? And does the Moon smell of cheese?
No. The Moon smells like gunpowder. It even tastes like gunpowder. But curiously only on the Moon:
(Another possibility is that) moondust "burns" in the lunar lander’s oxygen atmosphere. "Oxygen is very reactive," notes Lofgren, "and would readily combine with the dangling chemical bonds of the moondust." The process, called oxidation, is akin to burning. Although it happens too slowly for smoke or flames, the oxidation of moondust might produce an aroma like burnt gunpowder. (Note: Burnt and unburnt gunpowder do not smell the same. Apollo astronauts were specific. Moondust smells like burnt gunpowder.)
Curiously, back on Earth, moondust has no smell. There are hundreds of pounds of moondust at the Lunar Sample Lab in Houston. There, Lofgren has held dusty moon rocks with his own hands. He’s sniffed the rocks, sniffed the air, sniffed his hands. "It does not smell like gunpowder," he says.
Were the Apollo crews imagining things? No. Lofgren and others have a better explanation: Moondust on Earth has been "pacified." All of the samples brought back by Apollo astronauts have been in contact with moist, oxygen-rich air. Any smelly chemical reactions (or evaporations) ended long ago.
(The Smell of Moondust)