Some people, in all seriousness, say that humans

will be living in space within the next hundred or so

years. Planet Earth will be crowded, dirty and lack of 【S1】__

resources. A sort of exodus (移居) of mankind will

begin.

Spaceships will be assembled so that they revolve

around the earth. Some may orbit around Mars. These

space stations will be serviced by space buses. We saw

the first space bus launch in April 1981. This was 【S2】__

"Columbia", it made several orbits around the earth and 【S3】__

then returned, landing on a huge dry lake bed in

California. "Columbia" will be used again. Previous

spaceships have been abandoned, only the nose cone

being used to bring the crews back to earth. 【S4】__

Upon established, each space station will generate 【S5】__

its own atmosphere and have its own agriculture. It will

need to rotation to provide an artificial gravity; people 【S6】__

will be forced inwards from the centre by centrifugal 【S7】__

(离心力) force.

The moon and Mars could become new sources of

new materials. Driving through space will no longer 【S8】__

need Earth fuel—the energy would come from the

sun. This energy would be converted from electricity to 【S9】__

work magnetic rockets.

That all sounds quite fantastically but, with the 【S10】__

rapid development of modern technology, who knows

about what the future holds？

【S1】