Why do we love the smell of rain ?

Science is behind why many of us love the smell of rain.
The actual smell is a scent termed Petrichor which scientists have identified as the molecule Geosmin which is produced by a specific type of bacteria called Streptomyces.

When rain hits the ground or the leaves of trees and plants, Geosmin is released in the air and our sense of smell is sensitive to it particularly after new rain.

Petrichor (definition)

Petrichor originates from the Greek word petros, (stone) and ichor (the fluid that flows in the veins of the gods).

first used in "Nature of Argillaceous Odour", Isabel Joy Bear and Richard Thomas (Nature, 1964)