Porque a colonização do espaço é complicada

Today, the cheapest rockets available charge a little less than $1,000 to send 1 pound of material into low-earth orbit. Sending that pound to other planets, let alone the stars, would cost vastly more. To be sure, time and expense might be reduced by building space elevators and (should the laws of physics permit) taking advantage of handy wormholes. But the lesson of Zheng He remains: Exploration of distant lands will be a short-lived venture unless it yields something really, really valuable.