Elon Musk's work and Germany's contribution

Everyone knows Elon Musk – hardly anyone knows Hermann Oberth. Musk's high-flying rocket plans are based on the physicist's considerations: it was Oberth who, 100 years ago, was the first to calculate properly how a rocket can work with his book "The Rocket to the Planetary Spaces". Experts speak of the "father of space travel" and an "epochal discovery".

Without the foundations laid at that time, the space company SpaceX of founder Elon Musk would probably not be able to work on the gigantic rocket-spaceship system "Starship", which is supposed to bring people to Mars and the moon. Musk had announced that there would be a test flight at the beginning of the year – but it is currently unclear whether and when this will happen.

Stimulated by reading Jules Verne's lunar novels and his own astronomical observations, Hermann Julius Oberth had already worked on his first rocket plans as a high school student, as is known at the Museum and Archive for Space History in Oberth's place of residence, Feucht, in Franconia. In 1922, while studying physics in Munich, Göttingen and Heidelberg, he wrote the manuscript for his first work.

At that time, space travel played a role primarily in utopian novels, says museum director Karlheinz Rohrwild. "Oberth brought that to the level of possibility." The basic requirements are still the same: "Everything in the book is still relevant today."

Oberth cleared up two prejudices that were widespread at the time, explains Joachim Block, honorary professor at the TU Braunschweig and former head of several locations of the German Aerospace Center (DLR). On the one hand, it was assumed that rockets could not repel themselves anywhere in a vacuum and therefore could not fly.

On the other hand, according to Block, there was no fuel in the imagination at the time that could muster enough energy to maneuver its own weight out of the earth's gravitational field - let alone ballast like a rocket. "Oberth made it clear that a large part of the fuel does not even have to leave the gravitational field."

As anyone can see with rocket launches, a massive fireball is created while still on the ground. If rockets are built in several parts - so-called stages - which are gradually dropped, the mass to be transported into space becomes smaller and smaller. Oberth imagined liquid oxygen and spirit as fuel – the liquid rocket was designed.

The first stage of technological development was thus reached, as Block emphasizes. "The scientific breakthrough." In his book, Oberth also described possible application scenarios, as Michael Zuber from the Space Museum says. In today's terms, for example, it was about earth observation and climate measurement, communication between colonies and the mother country, but also about espionage purposes.

However, when Oberth wanted to do his doctorate with “The Rocket to the Planetary Spaces”, he failed in Germany. "His dissertation on the cosmic rocket was rejected by the University of Heidelberg as too fantastic," says the inventors' gallery of the German Patent and Trademark Office. Museum director Rohrwild says: There simply wasn't a professor back then who could have accepted the doctoral thesis based on the nature of his subjects.

Oberth moved back to Transylvania, in what is now Romania, to his wife and children. He completed his teacher training at the University of Cluj-Napoca – with part of the rejected dissertation as his thesis. Rohrwild describes the fact that the Munich publishing house Oldenbourg published “The rocket to the planetary spaces” in July 1923 as a courageous step. The book did not initially sell well.

But the young Wernher von Braun gets his hands on it. Paid for with savings, as Bernd Ruland's biography "Wernher von Braun - my life for space travel" says. "To my great surprise, the book was packed with math."

According to this, von Braun hardly understood anything, had just stayed behind because of his inability to do mathematics. "I then took the Oberth book to my mathematics teacher and asked him what I had to do to understand the content. He simply said to me: 'My dear friend, you have to learn mathematics first!'"

So he sat down on his pants and a few years later understood at least half of the book. Today, von Braun is considered the pioneer of rocket weapons under the Nazis in World War II.

Rohrwild and Zuber are convinced that it was not Oberth's intention to develop his approaches to weapons. He served as a soldier in World War I and as a medical student at the time as an assistant doctor in the hospital. Oberth was also never really political, and a trip to the NPD in the 1960s was more of a slip-up.

In 1928, as a scientific advisor to director Fritz Lang, Oberth was given the opportunity to undertake practical rocket tests during the production of the film "A Woman in the Moon". At times he took a leave of absence and worked in Switzerland, Germany, Italy and the USA. Because he invested a lot of his own money in his research, it drove him to the brink of ruin. "Actually a drama," says Rohrwild.

Again and again Oberth ended up in Feucht, where he was a sought-after expert until the 1970s – until the space race between the USA and the Soviet Union ended. After that it was quiet around him until his death in 1989. But many awards such as the Federal Cross of Merit honored his work.

Rohrwild explains that hardly a layman knows his name today with the very showdown of the great powers, each of which would have put their own national heroes on the space throne: the Russians Konstantin Ziolkowski, the Americans Robert Goddard. Germany had nothing to report on the subject in the post-war period.

An analysis from the National Air and Space Museum in Washington in 1996 also concluded that Oberth was the real father of space travel. Incidentally, he is also present at Musk's rocket factory SpaceX: A few years ago, she tweeted a photo of the sign on one of her conference rooms - named after Hermann Julius Oberth.