What happens after a SpaceX rocket drops off its payload? For Tom Mueller—SpaceX’s very first employee and the genius behind the Merlin engine—the answer is the foundation of a new multi-billion dollar empire. Forbes Reporter John Hyatt went inside the Los Angeles factory of Impulse Space to see how Mueller is solving the trillion dollar space economy's biggest bottleneck: the last mile. Discover why the man who helped Elon Musk conquer orbit is building a "taxi service for the cosmos," and why