space travel是什么意思

Space travel
, is a wonderful word! I believe that many people are very want to experience personally once, but expensive fee restrictions in the world the number of tourists, only a minority of people and astronaut can space travel. Common people can think, but to the continuous progress of science and technology in the future, I hope one day we can all to space travel, can even live in space, give the earth reduced pressure, for human find new living environment. That is, I believe by the earth into space by China to the United States is as convenient, people can like space travel, but now we can see.请加分采纳!

C.about
这本书是关于太空旅行的

Space travel bets on a dream. To design and build a spacecraft for space travel, you need to be able to figure out how big to make it, how heavy it can be, how fast it will have to go, how much fuel it needs and so forth. For that, you need a theory of how objects move in space and how to make the calculations. Over a period of nearly three centuries (from 1600 to 1900), three brilliant men - Johannes Kepler, Isaac Newton and Konstantin Tsiolkovsky, who said "the Earth is the cradle of mankind - one cannot remain in the cradle forever", worked out almost all the theories of space flight.



By 1951 space travel plans had become more grandiose. Famed rocket scientist Wernher von Braun predicted that a successful Mars mission could be accomplished with as few as 46 rockets in a round trip that would take three years. In a later interview with TIME, von Braun affirmed, "Man belongs wherever he wants to go - and he'll do plenty well when he gets there."



The space age began in 1957 when the Soviet Union launched Sputnik 1, the world's first man-made satellite. Also in 1957, Sputnik 2 was launched carrying Laika, a dog that was the first animal to orbit the Earth. In 1961, Yuri Gagarin became the first person to pilot a spacecraft. In 1963, the United States and the Soviet Union started a race to see who could put a man on the Moon first. In March of 1965, Alexei Leonov of the Soviet Union left his spacecraft to become the first person to walk in space. On July 20, 1969, the United States won when Neil Armstrong and Buzz Aldrin landed on the Moon's surface. The two superpowers have also put space stations into orbit around the Earth. These space structures serve as both a home and a laboratory for space travelers. The United States created and launched the first reusable manned spacecraft, the Space Shuttle, in 1981.

太空旅行

Space travel bets on a dream. To design and build a spacecraft for space travel, you need to be able to figure out how big to make it, how heavy it can be, how fast it will have to go, how much fuel it needs and so forth. For that, you need a theory of how objects move in space and how to make the calculations. Over a period of nearly three centuries (from 1600 to 1900), three brilliant men - Johannes Kepler, Isaac Newton and Konstantin Tsiolkovsky, who said "the Earth is the cradle of mankind - one cannot remain in the cradle forever", worked out almost all the theories of space flight.
By 1951 space travel plans had become more grandiose. Famed rocket scientist Wernher von Braun predicted that a successful Mars mission could be accomplished with as few as 46 rockets in a round trip that would take three years. In a later interview with TIME, von Braun affirmed, "Man belongs wherever he wants to go - and he'll do plenty well when he gets there."
The space age began in 1957 when the Soviet Union launched Sputnik 1, the world's first man-made satellite. Also in 1957, Sputnik 2 was launched carrying Laika, a dog that was the first animal to orbit the Earth. In 1961, Yuri Gagarin became the first person to pilot a spacecraft. In 1963, the United States and the Soviet Union started a race to see who could put a man on the Moon first. In March of 1965, Alexei Leonov of the Soviet Union left his spacecraft to become the first person to walk in space. On July 20, 1969, the United States won when Neil Armstrong and Buzz Aldrin landed on the Moon's surface. The two superpowers have also put space stations into orbit around the Earth. These space structures serve as both a home and a laboratory for space travelers. The United States created and launched the first reusable manned spacecraft, the Space Shuttle, in 1981.