Program facilitator Stefan Knutson of Hudson, Wis., lower left, explains the inside-out perspective of the world inside the Earth Balloon at the 77th annual Festival of Nations at St. Paul RiverCentre in St. Paul. The Teflon balloon, one of 10 in the country built by Twin Cities-based Earth Adventure, teaches viewers about earth science, the environment and geography. Approximately 3,000 composite images taken in the year 2000 were combined to depict the surface of the planet.