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英语新闻:我们为什么要移民火星?

2015-05-15    来源:普特英语听力    【      美国外教 在线口语培训

英语新闻:我们为什么要移民火星?

【相关阅读】
人类对火星的探索早在50年前就开始了,当前也有不少观测、探索火星的实验项目正在进行。在这一过程中,人类对火星的认识不断加深。科学家推测,几十亿年前的火星极可能很像今天的地球,有很厚的大气层,有水、有海洋,甚至有生命。然而,由于火星的地心引力太小,导致大气分子不断逃离,火星才变得像现在这样又冷又干,远古的生命也随之消失或隐藏到地下。此外,火星的大气层里已被证实存有少量甲烷,其来源至今还是个谜,它可能来自于化学反应,或由细菌产生——如果是后者,便是火星存在生命的有力证据。

我们从未在地球以外的星球发现过生命。假如火星上真有生命存在,火星生命有可能是几十亿年前较温暖时期生命的后裔,它们的化学生理基因是否和地球生命一样呢?火星生命的发源期应该和地球差不多,地球生命经过几十亿年激烈的竞争和进化,远古的原始生命已被淘汰殆尽。而火星由于气候的变化,进化终止而古老的生命形式得以保存,这将是火星给我们研究生命起源的宝贵资料。在未掌握发掘、保护火星生命的方法之前,千万不要破坏了这份宝藏。从长远看,寻找宜居星球是一种趋势,火星移民只是一个开始,仅就这个计划而言,要解决的问题还很多。

After careful selection, the global migration of Mars, 'Mars One' program, has selected 100 people as a shortlist from 500 volunteers. What makes the one-way trip so attractive, with no prospects of a return to Earth? Let's talk about Mars itself.

There is water on Mars. Due to low temperatures, water on Mars is in the form of ice beneath the surface. If the ice were to melt, there is enough water to cover the entire surface of Mars to a depth of 11 meters. Life cannot survive without water, and Mars therefore possesses this basic prerequisite in abundance.

Scientists speculate that billions of years ago, Mars was most probably like Earth, with a very thick atmosphere, water, ocean and even life. However, low gravity resulted in the loss of atmospheric molecules and therefore Mars become cold and dry and then life disappeared or hid underground.


In addition, a small amount of methane in the atmosphere of Mars has been confirmed, but its origin remains a mystery; it may come from a chemical reaction, or from bacteria - and if the latter, it means that life exists on Mars.

Technically, the biggest problem faced by the program is not technical, but the physical and psychological problems. Currently, flying to Mars from Earth takes about eight months. Such a long journey will bring a lot of problems to the migrants, such as muscle atrophy or osteoporosis caused by weight loss. In addition, more cosmic rays radiation may cause cancer, while psychological diseases may result from living in a confined space for a long time.

Furthermore, even if we successfully reach Mars, building a permanent base is also a challenge. Since the number of immigrants will be limited, most of the labor will rely on robots. Besides farming, food and finding water, the most urgent issue is how to produce oxygen.

So, should we migrate to Mars?

Earth's population is growing, and one possible solution is to allow some people to emigrate to other planets. If Earth were to collide with an asteroid, humanity will be destroyed, as happened with the extinction of the dinosaurs 70 million years ago.


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