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Mars

美式拼写

Scientists who study Mars have laid down the program that they can follow. To begin with, they will have to find out whether life has ever existed on the planet Mars in the past. Secondly they will have to make a reliable map of its surface. And finally, they will have to make a list of the gases. Above all, they will have to discover how much nitrogen it possesses, since nitrogen is 4/5 of the air we breathe. They are surprisingly optimistic about raising the temperature on Mars and believe it could be done in 200 years. It would take a bit longer, though, to transform the atmosphere so that human beings could live there. Scientists estimate that this will take 100,000 years.
研究火星的科学家列出了他们能做的项目。首先，他们要看看过去火星上到底有没有生命存在过。然后，他们需要一张可靠的火星表面地图。最后，他们还需要一张气体清单，尤其是需要看看火星上有多少氮气，毕竟氮气占我们吸入气体的五分之四。科学家们对提高火星温度表示非常乐观，认为能在200年之内做到。不过想要把大气层变成人类可以生存的状态还需要更久。科学家估计，这将需要10万年。