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Mars

zero，其他数字用阿拉伯数字

美式拼写

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.
科幻作家经常幻想人类在火星上生活。但如今，科学家开始认真看待这个问题了。这是非常值得推荐的，毕竟这有可能解决地球现在人口过多的问题。不过很显然，除非人们能自然地住在那儿，不然就不值得为之努力了。如果火星大气层和地球大气层相类似，那么这就是有可能的。可是事实上火星大气层基本都是二氧化碳。除此以外，还有其他需要克服的问题。比如，那儿的温度能从零下60度一直到零上15度。