Summary: The first plane to fly day and night on solar power took off Friday from Moffett Field in California, headed across the U.S. Two pilots will take turns flying 20-hour stretches apiece on the 5-leg trip, ending at New York's JFK Airport in early July. The Solar Impulse HB-SIA aircraft has the wingspan of a jumbo jet but the weight of a car, and will travel about 40 miles an hour.
