SOFIA is a Boeing 747SP extensively modified to carry a 45,000-pound (20 metric ton), 98.4-inch (2.5-meter) diameter infrared telescope assembly. SOFIA will fly at altitudes up to 45,000 feet (13.7 km) - above more than 99 percent of the Earth's water vapor - to capture infrared images and spectra not possible by even the largest ground-based telescopes. On Monday, May 21, 2007, NASA dedicated a unique astronomy aircraft to pioneering aviator Charles Lindbergh on the 80th anniversary of his historic transatlantic flight.