Fact #50
September 3, 2026That Amazing “Rain Smell” Has a Name — Petrichor
That earthy smell you notice when rain hits dry ground is called petrichor. Australian scientists Isabel Joy Bear and Richard Thomas coined the word in 1964, combining Greek words associated with stone and the mythical blood of the gods. The scent isn’t actually the smell of water. Rain helps release aromatic compounds that have accumulated in soil and on rocks. One important contributor is geosmin, an earthy-smelling chemical made by soil-dwelling bacteria. Raindrops can launch tiny aerosol droplets carrying these compounds into the air, where your nose picks them up.
Mini Facts
1
“Petrichor” was coined in 1964 in a scientific paper published in Nature.
2
The smell is often especially noticeable when rain arrives after a long dry spell.
3
Light and moderate rain can produce more scent-carrying aerosols than heavy rain.
4
Geosmin also contributes to the familiar earthy flavor of beets.