Dust is a fascinating substance. Our bodies are always shedding dust from our skin, hair, and nails, leaving little bits of DNA wherever we roam. Dust floats unseen through the air around us. It's light. It's hard to see unless it lands on a contrasting surface or crosses the path of a ray of sunshine. It can travel far and wide.

Earth collects more than 100 tons of cosmic dust a day. A speck of it might be in your rug. The unseen dust deeply embedded in our homes over many years becomes an archive of every "geochemical" substance that's ever entered our home.

All of history is recorded in the dust we create: the pollution we make, the fires we start, the chemicals we use, the volcanos that erupt. Scientists can learn about the Roman Empire through the dust that has been compressed each year for thousands of years into layers of ice sheets in Greenland.

Today, we talk about the science and politics of dust. We also talk to a cleaning expert who will take your questions about dust and an artist who makes dust bunnies--bunnies sculptures from dust.