Konstantin Tsiolkovsky

The Tsiolkovsky rocket equation, first published in 1903, describes how a rocket's change in velocity depends on its exhaust velocity and the ratio of its initial mass to its final mass. This equation remains a fundamental tool used by aerospace engineers to calculate fuel requirements and trajectories for space missions.

No, Tsiolkovsky was largely self-taught after losing his hearing to scarlet fever as a child, and he worked as a provincial school mathematics teacher in Kaluga, Russia. He developed his theories about spaceflight through independent reading, correspondence, and theoretical calculation, not laboratory or experimental work.

Tsiolkovsky wrote extensively about space elevators, rotating orbital habitats, and the eventual colonization of the solar system. He is frequently associated with the saying that 'Earth is the cradle of humanity, but mankind cannot stay in the cradle forever,' expressing his belief that space colonization was humanity's destiny.

Tsiolkovsky is recognized as one of the three founding fathers of modern rocketry, alongside Robert Goddard of the United States and Hermann Oberth of Germany. While Goddard built the first liquid-fueled rocket and Oberth influenced the German rocket program, Tsiolkovsky provided the earliest and most comprehensive theoretical framework for spaceflight.