How did gravity help Apollo 13

A brief history of space travel

Verne's vision hits a nerve in the technology-loving century of dawning industrialization. And that's no wonder: where the white spots on the earthly map continue to melt, the boundless curiosity and the urge to discover Homo sapiens seek new extraterrestrial goals - which must also be achieved through technical progress.

Hermann Oberth is also convinced of this. Born in Transylvania in 1894, he devoured Verne's "From Earth to the Moon" at the age of eleven. Oberth soon found out that a cannon was not suitable for transporting people to the moon: The travelers would not survive the pressure caused by the enormous acceleration. His way out is a machine that generates its own propulsion according to the recoil principle - in short: the rocket.

It starts comparatively slowly and only accelerates to top speed at the edge of the atmosphere. This protects the crew and reduces air friction that slows down the aircraft. Like the Russian Konstantin Ziolkowski (1857–1935) - like Oberth a passionate Jules Verne reader - he formulated the "basic rocket equation" and thus contributed to laying the scientific and technical foundations of space travel.

Independently of each other, the two pioneers of space travel also developed the principle of the step rocket: During the flight, the rocket quickly becomes lighter due to the consumption of heavy fuel and can thus continue to increase its speed. When a step is burned out, the empty shell is blasted off to reduce the weight further - this is the only way to achieve speeds of 28,000 kilometers per hour to overcome the force of gravity. The actual space capsule is just the tiny "tip of the iceberg" of the rocket, which is made up of 90 percent fuel, 9 percent rocket body and only 1 percent payload.

Oberth's book “The Rocket for Planetary Spaces” from 1923 summarizes the fundamentals of space physics and makes them understandable to a wide audience. However, the first liquid rocket ignited Robert Hutchings Goddard in Massachusetts in 1926. Oberth's first rocket motor for liquid fuels burns three years later. Young technicians and other rocket enthusiasts, including the student Wernher von Braun, help him with further experimental work on the “cone nozzle”.

He later became the technical director of the first rocket test center in Berlin-Kummersdorf and then in Peenemünde. From 1939 onwards, “Unit 4” was developed under his direction. Under the name "V2", the first functioning liquid rocket in the world is intended to secure victory for Nazi Germany as a "miracle weapon". After the defeat, the USA secured various rockets, construction plans and the know-how of Wernher von Braun and other German rocket scientists. For the most part, the Soviets go away empty-handed - nevertheless, space travel will start ten years later in what is now Kazakhstan.