Black iron sand and white glass beads mix and separate in this rotating sphere. Valves open and close the fourteen holes that connect the upper and lower chambers.

The entire sphere rotates to reset the phenomenon. Slight changes in the sand's angle of repose and feed rate effect the entire landscape as it constantly sculpts itself.

 

The Exploratorium
San Francisco, CA, USA

Rochester Museum of Science, NY

American Museum of Natural History, NY

Science Works
Ashland, OR, USA