Hermann Oberth

If there is a small rocket on top of a big one, and if the big one is jettisoned and the small one is ignited, then their speeds are added.

I refrained from writing another one, thinking to myself: Never mind, I will prove that I am able to become a greater scientist than some of you, even without the title of doctor.

The rockets can be built so powerfully that they could be capable of carrying a man aloft.

The rockets... can be built so powerfully that they could be capable of carrying a man aloft.

Our educational system is like an automobile which has strong rear lights, brightly illuminating the past. But looking forward things are barely discernible.