Ever since space travel began, there has been exactly one way to reach the heavens: rocket engines. But now an entirely new approach is set to launch-a strategy that fights the unyielding pull of gravity with the gentle push of sunlight. The anticipated December blastoff of the Cosmos 1 spacecraft from a Russian submarine will debut the age of solar sailing.
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.