Yellowstone Supervolcano: American Doomsday

Imagine a modern Pompeii, a time-bomb bigger than 1,000 Hiroshima bombs, or a disaster zone 10 million times the size of Ground Zero. Sounds impossible, but is it? Beneath the Earth's surface, hidden seven miles below America’s most famous National Park, lies the ultimate threat waiting to erupt -- a phenomenon known as a supervolcano. With the potential to become the biggest n...