SpaceX has helped reconceive the notion of a space program, showing that what was long viewed as a government function can be capably handled by a company. It dispatched the first privately funded liquid-fueled rocket to reach orbit. It’s the first private company to send a spacecraft to the International Space Station. And it’s the first organization of any type to land a first-stage orbital-capable rocket. Founder Elon Musk, who has said he wants to retire and die on Mars (presumably a long time from now), has said he keeps SpaceX private to prevent public investors from steering it in the wrong direction in pursuit of short-term profit. Perhaps its most improbable achievement so far: SpaceX is already profitable.