While you're just about to head to bed, over in Abu Dhabi the Solar Impulse team will attempt to fly around the world, powered by solar energy alone. While the plane takes off today in March, it won't likely return until late July, early August. The route will take in the sights of India, China, NYC and er, Phoenix, with final stops in Southern Europe and Africa before coming to land, finally. Watch the livestream take-off right after the break.
Pilots Bertrand Piccard and Andre Borschberg will split duties of flying the Solar Impulse 2: a plane that's wider than Boeing 747, but weights only 2.3 tonnes: naturally, weight's important when you're being powered by solar. Across the wingspan, the team has installed 17,000 solar cells, while high-capacity lithium batteries on board will power the flight in the night-time. (Each leg will take several days and nights to complete.)
Update: Takeoff's been delayed as the team runs through some last-minute technical checks. It looks brutally early in Abu Dhabi: presumably the team needs to maximize the sunlight that the plane can pick up.