A plane powered by the sun took off from Abu Dhabi on Monday for an unprecedented attempt at the first flight around the world, seeking to prove that flying is possible without using fossil fuel.

Solar Impulse 2 took off just after dawn on Monday and will have stopovers in India, Myanmar and China before crossing the Pacific Ocean and flying across the United States and southern Europe to arrive back in Abu Dhabi.

On its five-month journey of 35,000 km (22,000 miles), the engines will be powered only by solar energy. The two Swiss pilots will take turns at the controls in the tiny cabin for five consecutive days and nights in the air.

The plane, which has the weight of a family car (2,300 kg, 5,100 pounds) and a wingspan equal to that of the largest passenger airliners, will return by late July. Its journey will span approximately 25 flight days at speeds between 50 and 100 km (30 to 60 miles) per hour.