The Solar Impulse, a solar-powered single person plane that uses 12,000 solar cells to achieve flight, is in the middle of its first 24 hour flight attempt. If successful, it could pave the way for using solar energy as a viable energy source for long distance flights. The plane, which has had three other successful test flights before, will hit a max altitude of 27,900 feet. Let’s hope it makes it. Best of all, you can watch a live webcast of its flight here.