The Smell of Rain

Researchers at MIT might have found where the distinctive smell that frequently accompanies the first rain after a long period of warm, dry weather -also called petrichor - comes from.
When a raindrop hits a porous surface, it traps tiny air bubbles at the point of contact, which then float to the surface in a fizz of aerosols. The researchers suspect that in natural environments, aerosols may carry aromatic elements (along with bacteria and viruses stored in soil) and release that distinctive smell.

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