Step 1: Intensive reading.
Try to answer the question below while you’re reading:
Question: Which life forms are most likely to develop on a distant planet?
Vocabulary:
astronomy n .天文学
particle n .微粒，粒子
relative adj .相对的
Jupiter n .木星
infinitely adv .无限地，无穷地
blot v .遮暗
solar adj .太阳系的
analyse v .分析
Venus n .金星
bacteria n .细菌
Mars n .火星
oxygen n .氧气
orbit n .运行轨道
realm n .领域
astronomical adj .天文学的
endeavour n .努力
generate v .产生
Passage:
Recent developments in astronomy have made it possible to detect planets in our own
Milky Way and in other galaxies. This is a major achievement because, in relative
terms, planets are very small and do not emit light. Finding planets is proving hard
enough, but finding life on them will prove infinitely more difficult. The first question
to answer is whether a planet can actually support life. In our own solar system, for
example, Venus is far too hot and Mars is far too cold to support life. Only the Earth
provides ideal conditions, and even here it has taken more than four billion years for
plant and animal life to evolve.
天文学方面的最新发展使得我们能够在银河系和其他星系发现行星。这是一个重
要的成就，因为相对来说，行星很小，而且也不发光。寻找行星证明相当困难，
但是要在行星上发现生命会变得无比艰难。第一个需要解答的问题是一颗行星是
否有能够维持生命的条件。举例来说，在我们的太阳系里，对于生命来说，金星
的温度太高，而火星的温度则太低。只有地球提供了理想的条件，而即使在这里，
植物和动物的进化也用了 40 亿年的时间。
Whether a planet can support life depends on the size and brightness of its star, that is
its 'sun'. Imagine a star up to twenty times larger, brighter and hotter than our own sun.
A planet would have to be a very long way from it to be capable of supporting life.
Alternatively, if the star were small, the life supporting planet would have to have a
close orbit round it and also provide the perfect conditions for life forms to develop.
But how would we find such a planet? At present, there is no telescope in existence
that is capable of detecting the presence of life. The development of such a telescope
will be one of the great astronomical projects of the twenty-first century.
一颗行星是否能够维持生命取决于它的恒星—— 即它的“太阳”—— 的大小和亮
度。设想一下，一颗恒星比我们的太阳还要大，还要亮，还要热 20 倍，那么一
颗行星为了维持生命就要离它的恒星非常远。反之，如果恒星很小，维持生命的
行星就要在离恒星很近的轨道上运行，而且要有极好的条件才能使生命得以发展。
但是，我们如何才能找到这样一颗行星呢？现在，没有一台现存的望远镜可以发
现生命的存在。而开发这样一台望远镜将会是 21 世纪天文学的一个重要的研究
课题。
Notes:
1 Milky Way，银河。
2 Whether a planet can support life depends on…，一颗行星是否能支持生命取决
于……。在这句话中，以 whether 引导的名词性从句作句子的主语。
3 up to，直到。
It is impossible to look for life on another planet using earth-based telescopes. Our
own warm atmosphere and the heat generated by the telescope would make it
impossible to detect objects as small as planets. Even a telescope in orbit round the
earth, like the very successful Hubble telescope, would not be suitable because of the
dust particles in our solar system. A telescope would have to be as far away as the
planet Jupiter to look for life in outer space, because the dust becomes thinner the
further we travel towards the outer edges of our own solar system. Once we detected a
planet, we would have to find a way of blotting out the light from its star, so that we
would be able to 'see' the planet properly and analyse its atmosphere. In the first
instance, we would be looking for plant life, rather than 'little green men'. The life
forms most likely to develop on a planet would be bacteria. It is bacteria that have
generated the oxygen we breathe on earth. For most of the earth's history they have
been the only form of life on our planet. As Earth-dwellers, we always cherish the
hope that we will be visited by little green men and that we will be able to
communicate with them. But this hope is always in the realms of science fiction. If we
were able to discover lowly forms of life like bacteria on another planet, it would
completely change our view of ourselves. As Daniel Goldin of NASA observed,
'Finding life elsewhere would change everything. No human endeavour or thought
would be unchanged by it. '
使用放置在地球上的望远镜是无法观察到其他行星上的生命的。地球周围温暖的
大气层和望远镜散出的热量使得我们根本不可能找到像行星那么小的物体。即使
是一台放置在围绕地球的轨道上的望远镜—— 如非常成功的哈勃望远镜——也
因为太阳系中的尘埃微粒而无法胜任。望远镜要放置在木星那样遥远的行星上才
有可能在外层空间搜寻生命，因为我们越是接近太阳系的边缘，尘埃就越稀薄。
一旦我们找到这样一颗行星，我们就要想办法将它的恒星射过来的光线遮暗，这
样我们就能彻底“看见”这颗行星，并分析它的大气层。首先我们要寻找植物，而
不是那种“小绿人”。在行星上最容易生存下来的是细菌。正是细菌生产出我们在
地球上呼吸的氧气。在地球发展的大部分进程中，细菌是地球上唯一的生命形式。
作为地球上的居民，我们总存有这样的希望：小绿人来拜访我们，而我们可以和
他们交流。但是，这种希望总是只在科幻小说中存在。如果我们能够在另一颗行
星上找到诸如细菌那种低等生命，那么这个发现将彻底改变我们对我们自已的看
法。正如美国国家航空和宇宙航空局的丹尼尔 ·戈尔丁指出的：“在其他地方发现
生命会改变一切。任何人类的努力和想法都会发生变化。”
Notes:
4 earth-based telescopes，放置在地球上的望远镜。
5 in the realms of science fiction，在科幻小说中存在。
6 NASA，这是国家航空和宇宙航空局的首字母缩写（也可作 N.A.S.A.或
Nasa）。这个组织建于 1958 年，负责组织美国的航空宇航研究。它的巨大成功
之一便是 1969 年 7 月 21 日把一个人（内尔·阿姆斯特朗，乘“阿波罗 11”号宇宙
飞船）送上了月球。
55.2【阅读理解】From the earth: Greetings
Step 2: Comprehension questions.
1 What has made it possible to detect planets in our own Milky Way? (Recent
developments in astronomy.)
2 Why is this a major achievement? (Because planets are relatively very small and do
not emit light.)
3 Is finding planets proving hard? (Yes, it is.)
4 Will it prove more difficult to find life on distant planets? (Yes, it will)
5 In our own solar system, why can't Venus support life? (Because it is far too hot.)
6 And what about Mars? (It is far too cold.)
7 How long has it taken for life to evolve on earth? (More than four billion years.)
8 Whether a planet can support life depends on two things. What are they? (The size
and brightness of its star or ‘sun'.)
9 Is there any telescope in existence at present capable of detecting the presence of
life? (No, there isn't)
10 Will such a telescope be developed in the twenty-first century? (Possibly.)
11 Is it possible to look for life on other planets with earth-based telescopes? (No, it
isn't.)
12 Wouldn't the Hubble telescope be suitable, either? (No, it wouldn't.)
13 How far away would a telescope have to be? (As far away as the planet Jupiter.)
14 Why would we have to blot out the light from a planet's star? (To be able to see the
planet properly.)
15 Which life forms would be most likely to develop on another planet? (Bacteria.)
16 What have bacteria done on earth? (They have generated the oxygen we breathe.)
17 What does the writer think of the idea of our being visited by little green men? He
thinks it's science fiction.)
18 If we were to discover life on another planet, what would it do to our view of
ourselves? (It would completely change it.)
55.3【拓展写作】From the earth: Greetings
Step 3: Composition
Write a composition in about 300 words on the following:
• Extraterrestrials.
Key to composition
Plan and ideas for composition
Title: Extraterrestrials
Introduction: Remember ‘ET’? Ideas about extraterrestrials
Development: But creatures with incredible intelligence and no form? How to deal
with them? Not benevolent? Stories of extraterrestrials/aliens landing —have
scientists studied them? Extraterrestrials helping scientists? Stories just rumours?
Conclusion: Extraterrestrials out there in space? Perhaps one day we'll know: change
our view of everything
Composition
Do you remember ET in the film ET, the Extraterrestrial? If you do, you will
know that the common picture of extraterrestrials is that they will look rather
strange—for instance, they might have big eyes and funny feet and be a strange
colour—but they will still somehow look like living creatures from earth. At the same
time, of course, we believe that they will probably have incredible powers —like ET's
power to heal injuries and to come alive again. Many science-fiction stories and films
have shown aliens or extraterrestrials like this. They may somehow look like strange
earth creatures, therefore, but they are benevolent.
But what if extraterrestrials —beings from other planets —are creatures with
incredible intelligence and with no form, that is, with no body form like earthly
creatures? They might be almost ‘living thoughts’. How would we greet them? How
would we deal with them? And what if they are not benevolent? In other words, what
if they really want to take over the earth?
There are stories that extraterrestrials or aliens have already crashed on earth in
spacecraft (flying saucers) and that scientists have studied them. There are even more
fantastic stories that scientists are already learning from extraterrestrials new
knowledge which will help us build incredible spacecraft to fly to other planets and
beyond. Stories like that must surely be just rumours.
Perhaps one day we will know if there really are extraterrestrials out there in
space, and if there are, we will know what they look like and what they think of us.
Will they really be little green men? Or will they be giants? Or perhaps they will be so
small that we can hardly see them? Will they be friendly? Or will they want to take
over the earth? Who knows? One thing is certain. If we were ever to discover that
there are extraterrestrials out there, the discovery would completely change our view
of the universe and ourselves.
(329 words)
课外练习：
1 Why are planets in other solar systems so much more difficult to detect than stars?
(a) Because of the dust particles in our own solar system.
(b) Because of the limitations of earth-based telescopes.
(c) Because even the Hubble is not powerful enough to see beyond the Milky Way.
(d) Because planets are small and dark, and stars are large and radiant.
2 What do we know about the kind of planet, other than our own, that might be able to
support life?
(a) It will orbit closely round its star.
(b) It will be at least four billion years old.
(c) Its distance from its star will be such that it has a moderate temperature.
(d It will have an atmosphere capable of supporting bacteria.
3 A telescope capable of finding life on other planets would have to be .
(a) far enough from the centre of our solar system not to be affected by dust
(b) infinitely more powerful than even the very successful Hubble
(c) orbiting in a different solar system a long way away from our own
(d) on the planet Jupiter, on the edge of our solar system
4 It has become possible recent developments in astronomy to …
(a) caused by
(b) through
(c) as regards
(d) for
5 Venus is far too hot and Mars is too cold there to be any life.
(a) than
(b) whether
(c) for
(d) nor
6 A planet would have to be a very long way from .
(a) so big a star
(b) such big star
(c) a like star
(d) a star as this
7 At present, the telescope that is capable of detecting life.
(a) does not exist
(b) no exist
(c) cannot exist
(d) won't exist
8 in human endeavour or thought would be unchanged.
(a) All things
(b) Everything
(c) Nothing
(d) None
9 Imagine a star twenty times larger than our own sun.
(a) as much as
(b) as well as
(c) such as
(d) as if
10 The oxygen we breathe on earth has been by bacteria.
(a) manufactured
(b) fabricated
(c) produced
(d) given being
11 As Earth-dwellers, we that we will be visited by little green men.
(a) like to know
(b) fondly dream
(c) love to expect
(d) profoundly believe
12 No human endeavour or thought would be by it.
(a) unaltered
(b) ineffective
(c) unchallenged
(d) unchecked
答案：1b 2c 3a 4b 5c 6a 7a 8c 9a 10c 11b 12a