The molecules that give eggs, vinegar and nail polish remover their distinctive odor are also found in clouds of interstellar dust, says an article in the Wall Street Journal.
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Some folks had earlier said space smells like hot metal and seared meats.
Astronaut Thomas Jones said it “carries a distinct odor of ozone, a faint acrid smell…a little like gunpowder, sulfurous.”
Tony Antonelli, another space-walker, said space “definitely has a smell that’s different than anything else.”
A gentleman named Don Pettit was a bit more verbose on the topic: “Each time, when I repressed the airlock, opened the hatch and welcomed two tired workers inside, a peculiar odor tickled my olfactory senses,” Pettit recalled. “At first I couldn’t quite place it. It must have come from the air ducts that re-pressed the compartment. Then I noticed that this smell was on their suit, helmet, gloves, and tools. It was more pronounced on fabrics than on metal or plastic surfaces.” He concluded: it is hard to describe this smell; The best description I can come up with is metallic; a rather pleasant sweet metallic sensation. It reminded me of pleasant sweet smelling welding fumes. That is the smell of space.”