The idea of interplanetary travel is very old, but it is only during the past fifty years or so those astronautics have become a really practicable possibility. The Russian pioneer K. E. Tsiolkovsky suggested using rockets for space research as early as 1903 since rockets function by reaction motors and do not depend on a surrounding atmospheric medium.
He also suggested liquid propellants because solid propellants were too weak and hard to control. In 1926, the first modern type liquid-propellant rocket was sent up by R. H. Goddard in America. In Germany, intensive research was undertaken, culminating in the liquid-propellant V2 rocket, which bombarded England during the Second World War.
After the war, serious work on the future development of rocket travel continued in the U.S.S.R. and the United States. Before the Americans were ready to send up their first orbital satellite, Sinik was sent up by the Soviet Union In 1961, Russia took the world again by surprise by launching the first man into space—Yuri Gargarin, who completed a circuit of the Earth in free fall.
Who Is The First Astronaut In The World?
Yuri Alekseyevich Gagarin is the first astronaut in the world.