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For centuries people dreamed of going into space．This dream began to seem possible when high-flying rockets were built in the early 1900s.
In 1903 a Russian teacher named Konstantin Tsiolkovsky figured out how to use rockets for space travel．His plan was the first one in rocket science to use correct scientific calculation．About 30 years later, a U.S．scientist named Robert Goddard built the first rockets that could reach high altitudes．During World War II, German scientists built large rockets that could travel very far and carry dangerous explosives．After the war, scientists from Germany went to the United States and the Soviet Union to help those countries build space rockets.
These two countries were soon racing to get to space first．Each of these countries wanted to prove that it was stronger and more advanced than the other one．Both countries also had powerful bombs．People in the United States were worried when the Soviets were first to launch a space satellite, which was called Sputnik．The Soviets were also first to send a person into space．Yury Gagarin orbited the earth in the Vostok I spaceship in 1961.
The US government set a goal for its space program to be the first country to put a person on the Moon．The U.S．space program built a series of Apollo spaceship．These vehicles were powered by huge Saturn 5 rockets．In 1969 Apollo II took three men to the moon successfully．Nell Armstrong became the first person to walk on the Moon.
The Soviets may have lost the race to fly people to the Moon, but they built the first space station in 1971．The United States also built a space station．The space stations allowed people to live and work in space．Then the Soviet Union and the United States cooperated to hook two spaceships together in space．This action ended the "space race"．Today a much larger space station, built by several countries together, orbits Earth.
Another new way to go to space is by space shuttle．A space shuttle, first made in the United States in 1981, looks like an airplane．Astronauts who fly spaceships have used shuttles to help put satellites into space.
| History of space travel | ||
| Time | Events | Information concerned |
| Early 1900s | High-flying rockets were built. | It made the ancient dream of going to space possible to come （1） |
| 1903 | Konstantin Tsiolkovsky （2） out a way to use rockets for space travel. | He planned to put correct scientific calculation to use in rocket science. |
| Around （3） | Robert Goddard built new rockets. | The rockets could fly very （4） in the sky. |
| During and after World War II | German scientists built large rockets that could travel very far and carry dangerous explosives. | Germany was ahead of all the other countries in building space rockets and later it （5） the Soviet Union and the United States |
| The Soviet Union and the United States competed to get to space first. | The Soviet Union became the （6） of the competition when it launched the first satellite and sent the first astronaut into space. | |
| 1969 | The United States was （7） in putting a person on the moon. | In one way, it （8） the Soviet Union by becoming the first country to fly people to the moon. |
| 1970s | The Soviets built the first space station and was soon followed by Americans．And they finally ended the "space race" by （9） | Astronauts can live and work in space stations. |
| 1980s-- | Space shuttles are used as new vehicles for space （10） . | Shuttles are also used to help put satellites into space. |