A pair of Swiss pilots began their attempt to become the first to fly around the world in a solar-powered plane. Andre Borschberg and Bertand Piccard took off Sunday from Abu Dhabi in the Solar Impulse 2 on a trip that will see them hit every continent and cross both the Pacific and Atlantic oceans over the next five months. The aircraft plans to stop at different points around the world for both maintenance and a campaign initiative about clean technologies. The plane uses 17,000 solar cells on its wings as well lithium-ion batteries to fly at night. The first stop is Muscat, Oman.