Hovering landers or drones look as though they’re suspended in the air, because you can’t see the vortices caused by the propellers or the heat emitted by the thruster, or whatever mechanism enables the hovering. Well, here you can. And it proves that the act of hovering is anything but delicate.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.