Dirt

Dig into soil science and get the dirt on everything from mushrooms to meteorites.

Exploratorium physicist and Mars expert Paul Doherty pilots a tour of extraterrestrial dirt found as far away as Titan, Saturn's largest moon, and as near as your own home. Fellow staff scientist Bryce Johnson steers us through San Francisco Bay's sediments and Exploratorium biologist Karen Kalumuck reveals the creeping, crawling world inside a rotting log. And in an edible approach to our theme, mushroom farmers from Back to the Roots share secrets to growing gourmet mushrooms from coffee grounds.

Dirt also features compost demonstrations, urban farming explorations, special films, and an exhibition of historic color photographs documenting the end of the Dust Bowl era.