There are more living creatures in a shovel-full of dirt than human beings on the planet, yet more is known about the dark side of the moon than about soil. The Smithsonian and the Soil Science Society of America are out to change that.

An exhibit named “Dig It! The Secrets of Soil” is open through Jan. 3, 2010 at the Smithsonian’s National Museum of Natural History. It reveals the complex world of soil and how this hidden ecosystem supports nearly every form of life on Earth. Following its stay in Washington, D.C., the exhibit will travel to 10 museums around the nation through 2013. For more on the exhibit, go to