A solar-powered plane took off this morning for what will be the first exclusively sun-fueled cross-country flight. The Solar Impulse left a California airfield at 6am, and should ultimately land in Washington by mid-June, with five stops along the way, the Washington Post reports. It's the first solar-powered plane that can fly at night, but it comes with some daunting limitations: Its engines only put out 10 horsepower, it cruises at just 43mph, and it can't fly through clouds or take off or land in windy conditions.
The pilot, meanwhile, will be performing an impressive feat himself. The cockpit isn't pressurized or temperature-controlled, and it's the size of, in pilot and project co-founder Andre Borschberg's words, a "bad economy seat." Borschberg relies on meditation and advanced breathing techniques to endure the extreme heat and cold and stay focused; the plane's other pilot, co-founder Bertrand Piccard, uses self-hypnosis. (Read more Solar Impulse stories.)