Krafft Ehricke not only helped pioneer some of the earliest modern, liquid-propellant rockets, but also lived to develop workhorse boosters for the space age and concepts for lunar mining and planetary exploration now in the works. He envisioned the Moon as a stepping-stone, a role it played in several ways throughout humanity’s development starting long ago. He had a clever way of stating the profoundly obvious.

Ehricke’s life-span saw astounding human achievements: harnessing amazing new energy sources, traveling hundreds of times faster than ever before, probing scales millions of times larger and thousands of times smaller than imagined before, and transforming the Moon and planets from dreamlands to mapped worlds. We once ascribed romantic notions to the Moon; now we see how alien worlds differ from Earth and distant worlds of our imagination.