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新概念第四冊(cè)Lesson37課文翻譯及學(xué)習(xí)筆記
【課文】
First listen and then answer the following question.
聽錄音，然后回答以下問題。
What is the most important factor, both in government or business, for keeping running costs low?
If a nation is essentially disunited, it is left to the government to hold it together. This increases the expense of government, and reduces correspondingly the amount of economic resources that could be used for developing the country. And it should not be forgotten how small those resources are in a poor and backward country. Where the cost of government is high, resources for development are correspondingly low.
This may be illustrated by comparing the position of a nation with that of a private business enterprise. An enterprise has to incur certain costs and expenses in order to stay in business. For our purposes, we are concerned only with one kind of cost -- the cost of managing and administering the business. Such administrative overheads in a business are analogous to the cost of government in a nation. The administrative overheads of a business are low to the extent that everyone working in the business can be trusted to behave in a way that best promotes the interests of the firm. If they can each be trusted to take such responsibilities. and to exercise such initiative as falls within their sphere, then administrative overheads will be low. It will be low because it will be necessary to have only one man looking after each job, without having another man to check upon what he is doing, keep him in line, and report on him to someone else. But if no one can be trusted to act in a loyal and responsible manner towards his job, then the business will require armies of administrators, checkers, and foremen and administrative overheads will rise correspondingly. As administrative overheads rise, so the earnings of the business after meeting he expense of administration, will fall; and the business will have less money to distribute as dividends or invest directly in its future progress and development.
It is precisely the same with a nation. To the extent that the people can be relied upon to behave in a loyal and responsible manner, the government does not require armies of police and civil servants to keep them in order. But if a nation is disunited, the government cannot be sure that the actions of the people will be in the interests of the nation; and it will have to watch, check, and control the people accordingly. A disunited nation therefore has to incur unduly high costs of government.
RAYMOND FROST The Backward Society
【New words and expressions 生詞和短語(yǔ)】
hub n. (活動(dòng)的)中心
disunited adj. 分裂的
correspondingly adv. 相應(yīng)地
backward adj. 落后的
incur v. 承擔(dān)
administer v. 管理
adminstrative adj. 行政管理的
analogous adj. 類似的
overheads n. 一般費(fèi)用
initiative n. 主動(dòng)，積極性
checker n. 檢查人員
foreman n. 監(jiān)工
dividend n. 紅利
unduly adv. 過度地
【課文注釋】
1.disunited adj. 分裂的
例句：Moreover, when the employees are disunited, unhappiness is bound to set in.
更何況大家都不團(tuán)結(jié)時(shí)，不愉快事件頻頻。
You are wretched, disunited individuals.
你們?cè)阃噶�，分崩離析了。
disunite vt. 使分離, 使不和
例句：The issue disunited the party members.
該問題在黨員中造成分裂。
2.correspondingly adv. 相應(yīng)地
例句：The language correspondingly became stiffer.
講話的語(yǔ)言也相應(yīng)地變得更加強(qiáng)硬。
3.economic resources 經(jīng)濟(jì)資源
4.backward adj. 向后的, 落后的
例句：He took a backward step and ran away.
他向后退了一步,跑了。
This part of the country is still backward.
這個(gè)國(guó)家的這個(gè)地區(qū)仍很落后。
【詞義辨析】
back, backward, hind, behind 這些詞均有“在后，向后”之意。
back: 作為副詞或形容詞時(shí)，強(qiáng)調(diào)所修飾物的位置以及動(dòng)作運(yùn)動(dòng)方向。
backward: 可用于人或物，指向后的，落后的或遲鈍的。
hind: 指成對(duì)并且分前后的東西的“后面的”。
behind: 指一物同它物相對(duì)的位置或場(chǎng)所。
5.stay in business 維持營(yíng)業(yè)
6.be analogous to 與...相似
例句：The human heart is analogous to a pump.
人的心臟和泵類似。
7.initiative
n.
①主動(dòng)權(quán)，主動(dòng)性
例句：In the economic trend of the new era, having the initiative is the key.
在新時(shí)期的經(jīng)濟(jì)大潮中，擁有主動(dòng)權(quán)是關(guān)鍵。
I put it all down to her hard work and initiative.
我把這一切歸因于她工作又勤奮又主動(dòng)。
② 首創(chuàng)精神
例句：It is innovation plus initiative that has kept it thriving.
創(chuàng)新與進(jìn)取精神使得它蓬勃發(fā)展。
adj.
�、賱�(chuàng)始的
例句：The articles of incorporation usually name the initial directors.
通常情況下，公司的組織章程應(yīng)記載創(chuàng)始董事的姓名。
②初步的
例句：The panel's initial findings have now been made public.
這個(gè)委員會(huì)的初步調(diào)查結(jié)果已經(jīng)公布于眾。
�、圩园l(fā)的
例句：She took an initiative part in the Wildlife Conservation Society.
他們自發(fā)牽制住了敵人。
8. as falls within their sphere 屬于他們分內(nèi)的。
9.keep someone in line 控制住某人
例句：It's difficult to keep a group of young children in line.
讓小孩都老老實(shí)實(shí)的可真不易.
【反義詞】
out of line
例句：Don't get out of line at dinner or you will be punished.
晚飯時(shí)給我老實(shí)點(diǎn)要不我就收拾你.
10.keep them in order 管理他們
11.in the interests of 符合......的利益
例句：We work in the interests of the people.
我們是為人民群眾的利益而工作。
12.unduly adv. 過度地，不適當(dāng)?shù)?/p>
例句：An eccentric person, especially one who is unduly zealous.
異人古怪的人，尤指過分狂熱的人
【參考譯文】
如果一個(gè)國(guó)家實(shí)際上處于分裂狀態(tài)，使之聯(lián)合起來就是政府的事了。這樣的一來就增加了政府的開支，從而相應(yīng)地減少了可以用來發(fā)展國(guó)家的那部分經(jīng)濟(jì)資源。不應(yīng)忘記，在一個(gè)貧窮落后的國(guó)家里，那部分財(cái)力是很有限的。凡是政府管理費(fèi)用高的地方，用于發(fā)展國(guó)家經(jīng)濟(jì)的資金就會(huì)相應(yīng)地減少。
把國(guó)家的狀況同私人企業(yè)的狀況加以比較，就可以看清這個(gè)問題。一個(gè)企業(yè)為了繼續(xù)經(jīng)營(yíng)，不得不支出一定的費(fèi)用和開銷。就我們的目的而言，我們只關(guān)心一種費(fèi)用 -- 企業(yè)行政管理費(fèi)。一家企業(yè)的行政管理開支類似于一個(gè)國(guó)家的政府管理所用的開支。如果企業(yè)中的每個(gè)人都在真誠(chéng)地為提高企業(yè)利潤(rùn)而工作，那么企業(yè)的管理費(fèi)用就會(huì)降低到相應(yīng)的程度。如果企業(yè)的每個(gè)人都信得過，人人都認(rèn)真負(fù)責(zé)，在各自的工作范圍內(nèi)發(fā)揮主動(dòng)性，行政管理費(fèi)用就會(huì)降低。行政管理費(fèi)用降低的原因是：每項(xiàng)工作只需要一個(gè)人去完成，用不著另外再有一個(gè)人檢查工作。督促他遵守章程，或向有關(guān)人士匯報(bào)他的工作。但是，如果企業(yè)中誰(shuí)也不可信賴會(huì)對(duì)工作盡忠守職，那么企業(yè)就會(huì)需要大批的管理人員、檢查人員和帶班人員，管理費(fèi)用就會(huì)相應(yīng)地增加。管理費(fèi)用增加了，那么在扣除管理費(fèi)用后，企業(yè)的收入就降低了。因此用于分紅的金額或直接用于將來開拓和發(fā)展的投資就相應(yīng)地減少了。
一個(gè)國(guó)家的情況也完全相同。如果人民忠于職守，舉止規(guī)矩，能受到政府的信賴，那么政府就不需要大批的警察和文職人員去促使人民遵紀(jì)守法。但是，如果一個(gè)國(guó)家處于分裂狀態(tài)，政府不能相信人民的行動(dòng)有利于國(guó)家，那么政府就不得不對(duì)人民進(jìn)行監(jiān)督、檢查和控制。因此，一個(gè)處于分裂的國(guó)家必須要支付過高的行政管理費(fèi)用。
新概念第四冊(cè)Lesson38課文翻譯及學(xué)習(xí)筆記
【課文】
First listen and then answer the following question.
聽錄音，然后回答以下問題。
What does this text describe?
Contamination of water supplies is usually due to poor sanitation close to water sources, sewage disposal into the sources themselves, leakage of sewage into distribution systems or contamination with industrial or farm waste. Even if a piped water supply is safe at its source, it is not always safe by the time it reaches the tap. Intermittent tap-water supplies should be regarded as particularly suspect.
Travellers on short trips to areas with water supplies of uncertain quality should avoid drinking tap-water, or untreated water from any other source. It is best to keep to hot drinks, bottled or canned drinks of well-known brand names -- international standards of water treatment are usually followed at bottling plants. Carbonated drinks are acidic, and slightly safer. Make sure that all bottles are opened in your presence, and that their rims are clean and dry.
Boiling is always a good way of treating water. Some hotels supply boiled water on request and this can be used for drinking, or for brushing teeth. Portable boiling elements that can boil small quantities of water are useful when the right voltage of electricity is available. Refuse politely any cold drink from an unknown source.
Ice is only as safe as the water from which it is made, and should not be put in drinks unless it is known to be safe. Drink can be cooled by placing them on ice rather than adding ice to them.
Alcohol may be a medical disinfectant, but should not be relied upon to sterilize water. Ethanol is more effective at a concentration of 50-70 per cent; below 20 per cent, its bactericidal action is negligible. Spirits labelled 95 proof contain only about 47 per cent alcohol. Beware of methylated alcohol, which is very poisonous, and should never be added to drinking water.
If no other safe water supply can be obtained, tap water that is too hot to touch can be left to cool and is generally safe to drink. Those planning a trip to remote areas, or intending to live in countries where drinking water is not readily available, should know about the various possible methods for making water safe.
RICHARD DAWOOD Travellers' Health
【New words and expressions 生詞和短語(yǔ)】
contamination n. 污染
sanitation n. 衛(wèi)生，衛(wèi)生設(shè)備
sewage n. 污水
leakage n. 泄漏
intermittent adj. 間歇的，斷斷續(xù)續(xù)的
carbonated adj. 碳化的，碳酸的
acidic adj. 酸的，酸性的
alcohol n. 酒精
disinfectant n. 消毒劑
sterilize v. 消毒
ethanol n. 乙醇
bactericidal adj. 殺菌的
negligible adj. 可以忽略的，微不足道的
methylated adj. 加入甲醇的
【課文注釋】
1.be due to 因?yàn)? 由于
例句：His success was due to his industry and thrift.
他取得成功是由于他的勤儉。
Mr.Black bowed out of politics due to poor health.
布萊克先生由于健康不佳而退出政治生涯。
2.Intermittent adj. 間歇的, 斷斷續(xù)續(xù)的
例句：They saw the intermittent flashes from a lighthouse.
他們看見了燈塔發(fā)出一閃一滅的光。
There was intermittent debate about.
有過斷斷續(xù)續(xù)的辯論。
【詞形變化】
adv. intermittently
n. intermittence
3.untreated water 未經(jīng)處理的水
4.keep to 在本句意思為“局限于”
�、賵�(jiān)持
例句：Keeping to a strict diet is a question of mind over matter.
堅(jiān)持某一規(guī)定飲食，是毅力能否戰(zhàn)勝物質(zhì)誘惑的問題。
�、谧袷�
例句：In England traffic must keep to the left.
在英國(guó)，車輛必須靠左行駛。
You have to keep to your promise.
你得遵守諾言。
5.international standards 國(guó)際標(biāo)準(zhǔn)
6.portable adj. 輕便的, 手提式的
例句：The portable device easily knocks down.
這種輕便裝置容易拆卸。
The new portable computers are going like hot cakes.
新的便攜式計(jì)算機(jī)賣得很快。
7.voltage n. 電壓
8.Ice is only as safe as the water from which it is made 冰塊只是當(dāng)制造冰塊的水安全時(shí)才是安全的。
9.sterilize vt. 殺菌
例句：A dentist sterilizes his instruments.
牙科醫(yī)生給他的器具消毒。
10.concentration 濃度
例句：Titanium is useful at low concentration only.
鈦只在低濃度時(shí)起作用。
11.bactericidal action 殺菌能力
12.negligible adj. 可以忽略的, 微不足道的
例句：Details are negligible as far as I know.
我認(rèn)為這些細(xì)節(jié)完全可以忽略。
His knowledge of geography is negligible.
他的地理知識(shí)少得可憐。
【詞義辨析】
marginal, minor, negligible, minimal 這些形容詞均含“不重要的、次要的”之意。
marginal : 指處于邊緣，幅度、范圍小，故價(jià)值或重要性不大。
minor : 多指與別的比較后顯得不重要，或指較少、較小。
negligible : 指數(shù)量小，不重要，微不足道或可忽略不計(jì)。
minimal : 指少、低或小。
13.spirits 強(qiáng)度
14.remote areas 偏遠(yuǎn)地區(qū)
remote adj. 遙遠(yuǎn)的, 偏僻的, 遠(yuǎn)程的
例句：Mail comes to this remote village only once a week.
郵車每周只到這個(gè)偏僻的村莊。
【詞義辨析】
distant, far, remote 這些形容詞都含有“遠(yuǎn)的”之意。
distant: 語(yǔ)意強(qiáng)，強(qiáng)調(diào)距離。
far: 除特殊情況外，側(cè)重長(zhǎng)距離。也可用作引申意義。
remote: 側(cè)重指偏離中心地帶。
15.know about 知道......情況，了解
例句：I happened to know about him.
我正好了解一些他的情況。
I feel that I know about the value of my own work.
我覺得我知道自己工作的價(jià)值。
【參考譯文】
水源的污染通常是由于接近水源的地方衛(wèi)生條件太差而造成的：污水排入水源，污水滲入給水系統(tǒng)或工農(nóng)業(yè)污水造成污染。即使管道供水系統(tǒng)在水源處安全的，等水到達(dá)龍頭時(shí)就不一定總是安全的了。斷斷續(xù)續(xù)的水管應(yīng)該被視為是非�？梢傻�。
短途旅行到水質(zhì)不保險(xiǎn)的地區(qū)時(shí)，應(yīng)避免飲用水龍頭的水或未經(jīng)處理任何其他來源的水。好僅飲用開水，瓶裝或罐裝水 -- 裝瓶廠通常遵循國(guó)際水處理的標(biāo)準(zhǔn)。碳酸飲料是酸性的，就更安全一些。確保瓶子是當(dāng)你面開啟的，瓶口清潔干燥。
燒開一直是水處理的一種好辦法。有的酒店根據(jù)要求可提供開水，這些開水可用于飲用和刷牙。如果有相配的電壓，可以煮少量水的便攜式熱水裝置是有用的。應(yīng)謝絕任何不明來源的冷飲。
冰塊只有當(dāng)制造冰塊的水安全時(shí)才是保險(xiǎn)的，只有知道冰塊安全時(shí)才能加入飲料。可以把飲料置于冰塊之上來冷卻，而不是把冰塊加進(jìn)飲料之中。
酒精可能是醫(yī)學(xué)上的消毒劑，但決不可用來消毒飲用水。乙醇的濃度為50%至70%時(shí)比較有效，濃度低于20%時(shí)，殺菌能力基本上就不存在了。強(qiáng)度標(biāo)為95的酒中含有47%的酒精。要提防甲基化酒精，那是劇毒的，永遠(yuǎn)不能摻入飲用水。
如果沒有其他安全的飲用水，水管中流出的燙手的水可以留下來冷卻。這種水一般是安全的。那些計(jì)劃去偏遠(yuǎn)地區(qū)旅行，或在飲用水不現(xiàn)成的國(guó)家居住的人，應(yīng)該知道如何使水適于飲用的各種辦法。
新概念第四冊(cè)Lesson39課文翻譯及學(xué)習(xí)筆記
【課文】
First listen and then answer the following question.
聽錄音，然后回答以下問題。
What does the 'uniquely rational way' for us to communicate with other intelligent beings in space depend on?
We must conclude from the work of those who have studied the origin of life, that given a planet only approximately like our own, life is almost certain to start. Of all the planets in our solar system, we ware now pretty certain the Earth is the only one on which life can survive. Mars is too dry and poor in oxygen, Venus far too hot, and so is Mercury, and the outer planets have temperatures near absolute zero and hydrogen-dominated atmospheres. But other suns, start as the astronomers call them, are bound to have planets like our own, and as is the number of stars in the universe is so vast, this possibility becomes virtual certainty. There are one hundred thousand million starts in our own Milky Way alone, and then there are three thousand million other Milky Ways, or galaxies, in the universe. So the number of the stars that we know exist is now estimated at about 300 million million million.
Although perhaps only 1 per cent of the life that has started somewhere will develop into highly complex and intelligent patterns, so vast is the number of planets, that intelligent life is bound to be a natural part of the universe.
If then we are so certain that other intelligent life exists in the universe, why have we had no visitors from outer space yet? First of all, they may have come to this planet of ours thousands or millions of years ago, and found our then prevailing primitive state completely uninteresting to their own advanced knowledge. Professor Ronald Bracewell, a leading American radio astronomer, argued in Nature that such a superior civilization, on a visit to our own solar system, may have left an automatic messenger behind to await the possible awakening of an advanced civilization. Such a messenger, receiving our radio and television signals, might well re-transmit them back to its home-planet, although what impression any other civilization would thus get from us is best left unsaid.
But here we come up against the most difficult of all obstacles to contact with people on other planets -- the astronomical distances which separate us. As a reasonable guess, they might, on an average, be 100 light years away. (A light year is the distance which light travels at 186,000 miles per second in one year, namely 6 million million miles.) Radio waves also travel at the speed of light, and assuming such an automatic messenger picked up our first broadcasts of the 1920's, the message to its home planet is barely halfway there. Similarly, our own present primitive chemical rockets, though good enough to orbit men, have no chance of transporting us to the nearest other star, four light years away, let alone distances of tens or hundreds of light years.
Fortunately, there is a 'uniquely rational way' for us to communicate with other intelligent beings, as Walter Sullivan has put it in his excellent book, We Are not Alone. This depends on the precise radio frequency of the 21-cm wavelength, or 1420 megacycles per second. It is the natural frequency of emission of the hydrogen atoms in space and was discovered by us in 1951; it must be known to any kind of radio astronomer in the universe.
Once the existence of this wave-length had been discovered, it was not long before its use as the uniquely recognizable broadcasting frequency for interstellar communication was suggested. Without something of this kind, searching for intelligences on other planets would be like trying to meet a friend in London without a pre-arranged rendezvous and absurdly wandering the streets in the hope of a chance encounter.
ANTHONY MICHAELIS Are There Strangers in Space? from The Weekend Telegraph
【New words and expressions 生詞和短語(yǔ)】
Mercury n. 水星
hydrogen n. 氫氣
prevailing adj. 普遍的
radio astronomer 射電天方學(xué)家
uniquely adv. 地
rational adj. 合理的
radio frequency 無(wú)線電頻率
cm n. 厘米
megacycle n. 兆周
emission n. 散發(fā)
intersteller adj.星際的
rendezvous n. 約會(huì)地點(diǎn)
【課文注釋】
1.that given a planet only approximately like our own, life is almost certain to start 這是一個(gè)賓語(yǔ)從句，作動(dòng)詞conclude的賓語(yǔ)，其中g(shù)iven a planet...our own,過去分詞短語(yǔ)作條件狀語(yǔ)，given與if的意思相近，這個(gè)過去分詞短語(yǔ)可譯成“如果一個(gè)行星與我們所在的行星大致相同的話”。
2.life is almost certain to start 那幾乎肯定會(huì)產(chǎn)生生命。
3.be bound to 必然, 必定
例句：You are bound to feel tired after a long walk.
長(zhǎng)時(shí)間步行后你必然會(huì)感到疲勞。
He's bound to notice your mistake.
他必定會(huì)覺察到你的錯(cuò)誤。
4.prevailing adj. 盛行很廣的, 普遍的
例句：Your price is out of line with the prevailing international market.
你方價(jià)格與現(xiàn)行世界市場(chǎng)行情不一致。
He wore his hair in the prevailing fashion.
他的頭發(fā)梳的是當(dāng)時(shí)盛行的發(fā)型。
5.is best left unsaid 好不去說(它)
6.come up against 遇到，突然(或意外)，碰到(困難、反對(duì)等)
例句：He often came up against the problem of money.
他那時(shí)常常碰到錢的問題。
We expect to come up against a lot of opposition to the scheme.
我們預(yù)計(jì)這個(gè)計(jì)劃要遭到很多人反對(duì)。
7.reasonable adj.
�、俸侠淼�,
例句：The management took all reasonable safety precautions.
管理部門采取了一切合理的安全措施。
All you need is reasonable doubt.
你所需要的是合理懷疑。
②通情達(dá)理的,
例句：You are fortunate to have such a reasonable father.
你有這樣一位通情達(dá)理的父親，真是幸運(yùn)。
�、酃竭m度的
例句：At first sight their demands seemed reasonable.
乍看之下,他們的要求似乎公平合理。
8.emission n.
�、偕l(fā)
例句：In addition, wetland soils are known for methane emission, a greenhouse gas.
此外,濕地散發(fā)沼氣這種溫室氣體,是人所共知的。
②發(fā)行
例句：The limitless emission of foreign currencies has an serious influence on the
country's economy.
外匯的無(wú)限制發(fā)行嚴(yán)重影響了該國(guó)的經(jīng)濟(jì)。
�、叟欧�
例句：Emission of smoke from chimneys is an offense.
在這里排放煙霧是違法的事情。
9.absurdly wandering the streets in the hope of a chance encounter 荒唐得在街上
游逛，以期碰巧遇上一樣。
10.absurdly
例句：For there was never proud man thought so absurdly well of himself, as the lover
doth of the person loved; and therefore it was well said, That it is impossible to
love, and to be wise.
因?yàn)樯踔硫湴恋娜耍哺试冈谇槿嗣媲白暂p自賤。所以古人說得好：“就是神在
愛情中也難保持聰明。”
11.wander v. 漫步，閑逛，徘徊
例句：I like to wander in the park after dinner.
我喜歡晚飯后在公園里閑逛。
The boy was wandering around.
男孩在那周圍徘徊。
He likes to wander over the countryside.
他喜歡在鄉(xiāng)間漫步。
The river wanders through some beautiful country.
這條河蜿蜒曲折地流經(jīng)一些風(fēng)景秀麗的鄉(xiāng)村。
12.encounter
�、賜.意外的相見, 邂逅, 遭遇
例句：If both participate, it may be an actual encounter of bodiless consciousness.
如果是雙向的，這會(huì)是一個(gè)真實(shí)的與靈魂的相見。
②v. 遇到，偶然碰到，遭遇
例句：Otherwise, we will encounter grave difficulties.
否則便將遇到極大的困難。
I encountered an old friend at Rome.
我在羅馬邂逅了一個(gè)老朋友。
Don't be afraid to encounter risks.
不要害怕遭遇危險(xiǎn)。
【參考譯文】
根據(jù)研究生命起源的人們所作的工作，我們必然會(huì)得出這樣的結(jié)論：如果設(shè)想有一顆行星和我們地球的情況基本相似，那幾乎肯定會(huì)產(chǎn)生生命。我們目前可以肯定的是，在我們太陽(yáng)系的所有行星中，地球是生命能存在的行星。火星太干燥又缺氧，金星太熱，水星也一樣。除此之外，太陽(yáng)系的其他行星的溫度都接近絕對(duì)零度，并圍繞著以氫氣為主的大氣層。但是，其他的太陽(yáng)，既天文學(xué)家所說的恒星，肯定會(huì)有像我們地球一樣的行星。因?yàn)橛钪嬷泻阈堑臄?shù)目極其龐大，所以存在著產(chǎn)生生命星球的這種可能性是肯定無(wú)疑的。僅我們的銀河系就有1000億顆星，況且在宇宙中還有30億個(gè)天河，即銀河系。因此，我們所知道的現(xiàn)有恒星數(shù)目估計(jì)約有30億X1000億顆。
雖然在已經(jīng)產(chǎn)生生命的某個(gè)地方，可能只有1%會(huì)發(fā)展成高度復(fù)雜有智力的生命形態(tài)，但是行星的數(shù)目是那么龐大，有智力的生命必然是宇宙的自然組成部分。
既然我們?nèi)绱藞?jiān)信宇宙中存在著其他有智力的生命，那么我們?yōu)槭裁催�未見到外層空間來訪的客人呢?首先，他們可能在幾千年前或幾百年前已來過我們地球，并且發(fā)現(xiàn)我們地球那時(shí)普遍存在著的原始狀態(tài)同他們的先進(jìn)的知識(shí)相比是索然無(wú)味的。美國(guó)一位重要的射電天文學(xué)家羅納德.布雷斯韋爾教授在《自然》雜志上提出了這樣的觀點(diǎn)：假如有如此高級(jí)文明生命訪問了我們的太陽(yáng)系，很可能會(huì)在離開太陽(yáng)系時(shí)留下自動(dòng)化信號(hào)裝置，等待先進(jìn)文明的覺醒。這種自動(dòng)化信息裝置，在接收到我們的無(wú)線電和電視信號(hào)后，完全有可能把這些信號(hào)發(fā)回到原來的行星。至于其他文明行星對(duì)我們地球會(huì)有什么印象，還是不說為好。
然而，在和外星人聯(lián)系中我們遇到的大困難是分隔我們的天文距離。據(jù)合理推算，外星人離我們平均距離也有100光年之遠(yuǎn)(1光年是光以每秒186，000英里的速度在一年內(nèi)走的距離即6萬(wàn)億英里)。無(wú)線電波也是以光速傳播的。假定外星人的這種自動(dòng)化信息裝置接收了我們二十世紀(jì)二十年代的第廣播信號(hào)，那么這個(gè)信號(hào)在發(fā)回到原來的行星途中剛剛走了一半路程。同樣，我們目前使用的原始化學(xué)火箭，雖然把人送入軌道，但尚不能把我們送到離我們近、相距4光年的其他星球上去，更不用說幾十光年或幾百光年遠(yuǎn)的地方了。
幸運(yùn)的是，有一種我們可以和其他智力生命通迅聯(lián)系的“合理的方法”，正如活爾特.沙利方在其杰作《我們并不孤獨(dú)》中闡述的。這種通迅聯(lián)系要靠21厘米波段，即每秒1420兆周的精確無(wú)線電頻率。這個(gè)頻率是空間氫原子釋放的自然頻率，是在1951年被人類發(fā)現(xiàn)的。這個(gè)頻率是宇宙中任何射電天文學(xué)家都應(yīng)該熟悉的。
一旦這種波長(zhǎng)的實(shí)際存在被發(fā)現(xiàn)，提出把它作為星際間可辨認(rèn)的廣播頻率就為期不遠(yuǎn)了。沒有這手段，要想尋覓其他星球上的智力生命，就如同去倫敦見一位朋友，事先未約定地點(diǎn)，而荒唐地在街上游逛，以期待碰巧遇上一樣。
