By this stage, Facebook’s plan to bring internet to the whole world with a fleet of drones and lasers is pretty well documented: what’s a little vague has been the details, until now. Speaking at the Social Good Summit in New York, Yael Maguire, the engineering director at Facebook Connectivity Lab, spilled a few details. The ‘unmanned planes’ will be about the size of a 747, but far lighter, and solar-powered. In theory, that combination of huge wingspan will let the ‘planes’ fly more or less indefinitely, at high altitudes – 60,000 feet or more, in order to stay above the weather, and other aircraft.