We Can Go There: How Did We Miss This?

Have you ever wondered why NASA and other space agencies have been telling us that moving payloads outside Earth orbit is so hard? The short answer is the rocket equation. The long answer is that space propulsion was focused on two major methods, carrying the fuel with the payload, or collecting propulsive energy from a remote source. Every serious space project since we've gone to space has done one or the other, either carrying all the required fuel away from Earth orbit in one mass, or r...