We Know What Other Planets Smell Like, And It's Not All Pleasant
You've probably thought about how it would look and feel to walk on other planets in our solar system, but we bet you've never thought about how it would smell. Luckily, scientists have. The answer? Not like roses, that's for sure.
How Do They Know?
Astronomers have a good idea of how other planets would smell based on their composition. A lot of sulfur in the atmosphere, like that of Venus or Mars? The air probably stinks like rotten eggs. Jupiter actually has multiple layers with slightly different smells—the outer layers have a lot of ammonia, so they'd smell like window cleaner, while the inner layers smell like bitter almonds due to their hydrogen cyanide content. We know what you're thinking: what does Uranus smell like? Sorry to ruin the joke, but it wouldn't really have a smell. Its atmosphere is made up of mostly hydrogen and helium, which aren't very smelly.
What We've Really Smelled
For some astronomical bodies, we don't have to guess. We've been to the moon, for example, so we have astronauts who can attest that moon dust smells like gunpowder (they didn't smell it during moonwalks, of course, but the dust was clingy enough to get everywhere inside the spacecraft). Strangely, its makeup isn't anything like gunpowder: it's mainly silicon dioxide, and it's also rich in iron, calcium and magnesium. But don't take our word for it; there's audio from lunar missions about the explosive smell. "I wish I could send you some," said Apollo 17 astronaut Gene Cernan. "It's amazing stuff...it smells like spent gunpowder."