The journey took a very long time—505 days to fly 26,000 miles (42,000 km) at an average speed of about 45 mph (70 kph)—but pilots Bertrand Piccard and Andre Borschberg successfully landed the Solar Impulse 2 aircraft in Abu Dhabi on Tuesday, after flying around the world using only the power of the Sun. Solar Impulse 2 is a solar-powered aircraft equipped with more than 17,000 solar cells that weighs only 2.4 tons with a wingspan of 235 ft (72 m). Technical challenges, poor flying conditions, and a delicate aircraft all contributed to the slow pace. Gathered here are images from the record-setting circumnavigation, undertaken to help focus the world’s efforts to develop renewable energy sources.