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Mars

zero，其他數(shù)字用阿拉伯?dāng)?shù)字

美式拼寫

Science fiction writers have often imagined human beings going to live on Mars. But these days, scientists are taking the idea seriously. It has a great deal to recommend it, since it might solve the problem of overcrowding on the earth. But obviously, it would not be worth making the effort unless people could live there naturally. If the atmosphere were like that of the earth, this might be possible. But in fact it is mostly carbon dioxide. Apart from that, there are other problems to be overcome. For example, the temperature would have to be raised from 60 degrees below zero to 15 degrees above it.
科幻作家經(jīng)?；孟肴祟愒诨鹦巧仙?。但如今，科學(xué)家開始認(rèn)真看待這個問題了。這是非常值得推薦的，畢竟這有可能解決地球現(xiàn)在人口過多的問題。不過很顯然，除非人們能自然地住在那兒，不然就不值得為之努力了。如果火星大氣層和地球大氣層相類似，那么這就是有可能的?？墒鞘聦嵣匣鹦谴髿鈱踊径际嵌趸?。除此以外，還有其他需要克服的問題。比如，那兒的溫度能從零下60度一直到零上15度。