Researchers at Solar Impulse in Lausanne, Switzerland, are designing a solar-powered, single-pilot aircraft they hope will circumnavigate the globe in 2010.

In order to generate enough electricity from photovoltaic panels on the tops of its wings, the craft will need a wingspan of 80 meters -- about that of the new superjumbo Airbus A380 jet; at the same time, however, its weight can't exceed 2,000 kilograms.

Meeting these constraints requires pushing the limits of materials and design and superoptimizing electrical components, batteries, and power management systems. Leading the plane's development is the Swiss adventurer Bertrand Piccard; in 1999, he and a partner became the first people to fly nonstop around the world in a balloon.