I do not know what I seem to the world, but to myself I appear to have been like a boy playing upon the seashore and diverting myself by now and then finding a smoother pebble or prettier shell than ordinary, while the great ocean of truth lay before me all undiscovered.
Isaac Newton, English philosopher and physicist, 1727
To set foot on the soil of the asteroids, to lift by hand a rock from the Moon, to observe Mars from a distance of several tens of kilometers, to land on its satellite or even on its surface, what can be more fantastic? From the moment of using rocket devices a new great era will begin in astronomy: the epoch of the more intensive study of the firmament.
Konstantin E. Tsiolkovsky, Father of Russian Astronautics, 1896