Warfighters have plenty of eyes in the sky, with a massive drone fleet and a satellite network that can spot their locations on the ground. But satellites are only helpful when they’re overhead, and battlefield situations can’t wait for orbital physics. To solve this problem, DARPA wants a swarm of cheap satellites nestled between the big ones up above and the aerial drones down below.
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.