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皖北矿务局总医院修眉多少钱排名活动蚌埠东方美莱坞整形美容医院吸脂手术怎么样

2017年12月11日 23:29:21
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I work on the night shift. 我上夜班。night shift:夜班, 夜班工人 /201701/474170怀远县做眼袋手术多少钱Text Are we humans alone in the universe? Or is there intelligent life on other planets? These questions are not new. What is new, however, is the scientific attempt to discover whether or not other planets beyond our own have given birth to advanced civilizations. In the following article, the author describes the scientific means now available for investigating this possibility and discusses how probable it is that we are not alone in the universe. THE QUEST FOR EXTRATERRESTRIAL INTELLIGENCE Carl Sagan Through all of our history we have pondered the stars and mused whether humanity is unique or if, somewhere else in the dark of the night sky, there are other beings who contemplate and wonder as we do, fellow thinkers in the cosmos. Such beings might view themselves and the universe differently. Somewhere else there might be very exotic biologies and technologies and societies. In a cosmic setting vast and old beyond ordinary human understanding, we are a little lonely; and we ponder the ultimate significance, if any, of our tiny but exquisite blue planet. The search for extraterrestrial intelligence is the search for a generally acceptable cosmic context for the human species. In the deepest sense, the search for extraterrestrial intelligence is a search for ourselves. In the last few years -- in one-millionth the lifetime of our species on this planet -- we have achieved an extraordinary technological capability which enables us to seek out unimaginably distant civilizations even if they are no more advanced than we. That capability is called radio astronomy and involves single radio telescopes, collections or arrays of radio telescopes, sensitive radio detectors, advanced computers for processing received date, and the imagination and skill of dedicated scientists. Radio astronomy has in the last decade opened a new window on the physical universe. It may also, if we are wise enough to make the effort, cast a profound light on the biological universe. Some scientists working on the question of extraterrestrial intelligence, myself among them, have attempted to estimate the number of advanced technical civilizations -- defined operationally as societies capable of radio astronomy -- in the Milky Way Galaxy. Such estimates are little better than guesses. They require assigning numerical values to quantities such as the numbers and ages of stars; the abundance of planetary systems and the likelihood of the origin of life, which we know less well; and the probability of the evolution of intelligent life and the lifetime of technical civilizations, about which we know very little indeed. When we do the arithmetic, the sorts of numbers we come up with are, characteristically, around a million technical civilizations. A million civilizations is a breathtakingly large number, and it is exhilarating to imagine the diversity, lifestyles and commerce of those million worlds. But the Milky Way Galaxy contains some 250 billion stars, and even with a million civilizations, less than one star in 200,000 would have a planet inhabited by an advanced civilization. Since we have little idea which stars are likely candidates, we will have to examine a very large number of them. Such considerations suggest that the quest for extraterrestrial intelligence may require a significant effort. Despite claims about ancient astronauts and unidentified flying objects, there is no firm evidence for past visitation of the Earth by other civilizations. We are restricted to remote signaling and, of the long-distance techniques available to our technology, radio is by far the best. Radio telescopes are relatively inexpensive; radio signals travel at the speed of light, faster than which nothing can go; and the use of radio for communication is not a short-sighted or anthropocentric activity. Radio represents a large part of the electromagnetic spectrum and any technical civilization anywhere in the Galaxy will have discovered radio early -- just as in the last few centuries we have explored the entire electromagnetic spectrum from short gamma rays to very long radio waves. Advanced civilizations might very well use some other means of communication with their peers. But if they wish to communicate with backward or emerging civilizations, there are only a few obvious methods, the chief of which is radio. The first serious attempt to listen for possible radio signals from other civilizations was carried out at the National Radio Astronomy Observatory in Greenbank, West Virginia, in 1959 and 1960. It was organized by Frank Drake, now at Cornel University, and was called Project Ozma, after the princess of the Land of Oz, a place very exotic, very distant and very difficult to reach. Drake examined two nearby stars for a few weeks with negative results. Positive results would have been astonishing because as we have seen, even rather optimistic estimates of the number of technical civilizations in the Galaxy imply that several hundred thousand stars must be examined in order to achieve success by random stellar selection. Since Project Ozma, there have been six or eight other such programs, all at a rather modest level, in the ed States, Canada and the Soviet Union. All results have been negative. The total number of individual stars examined to date in this way is less than a thousand. We have performed something like one tenth of one percent of the required effort. However, there are signs that much more serious efforts may be mustered in the reasonably near future. Besides, hand in hand with the recent spectacular advances in radio technology, there has been a dramatic increase in the scientific and public respectability of the entire subject of extraterrestrial life. A clear sign of the new attitude is the Viking missions to Mars, which are to a significant extent dedicated to the search for life on another planet. But along with the burgeoning dedication to a serious search, a slightly negative note has emerged which is nevertheless very interesting. A few scientists have lately asked a curious question: If extraterrestrial intelligence is abundant, why have we not aly seen its manifestations? Skeptics also ask why there is no clear evidence of extraterrestrial visits to Earth. We have aly launched slow and modest interstellar spacecraft. A society more advance than ours should be able to ply the spaces between the stars conveniently if not effortlessly. Over millions of years such societies should have established colonies, which might themselves launch interstellar expeditions. Why are they not here? The temptation is to deduce that there are at most a few advanced extraterrestrial civilizations -- either because statistically we are one of the first technical civilizations to have emerged or because it is the fate of all such civilizations to destroy themselves before they are much further along than we. It seems to me that such despair is quite premature. All such arguments depend on our correctly surmising the intentions of beings far more advanced than ourselves, and when examined more closely I think these arguments reveal a range of interesting human conceits. Why do we expect that it will be easy to recognize the manifestations of very advanced civilizations? Is our situation not closer to that of members of an isolated society in the Amazon basin, say, who lack the tools to detect the powerful international radio and television traffic that is all around them? Also, there is a wide range of incompletely understood phenomena in astronomy. Might the modulation of pulsars or the energy source of quasars, for example, have a technological origin? Or perhaps there is a galactic ethic of noninterference with backward or emerging civilizations. Perhaps there is a waiting time before contact is considered appropriate, so as to give us a fair opportunity to destroy ourselves first, if we are so inclined. Perhaps all societies significantly more advanced than our own have achieved an effective personal immortality and lose the motivation for interstellar gallivanting, which may, for all we know, be a typical urge only of adolescent civilizations. Perhaps mature civilizations do not wish to pollute the cosmos. There is a very long list of such "perhapses," few of which we are in a position to evaluate with any degree of assurance. The question of extraterrestrial civilizations seems to me entirely open. Personally, I think it far more difficult to understand a universe in which we are the only technological civilization, or one of a very few, than to conceive of a cosmos brining over with intelligent life. Many aspects of the problem are, fortunately, amenable to experimental verification. We can search for planets of other stars, seek simple forms of life on such nearby planets as Mars, and perform more extensive laboratory studies on the chemistry of the origin of life. We can investigate more deeply the evolution of organisms and societies. The problem cries out for a long-term, open-minded, systematic search, with nature as the only arbitor of what is or is not likely .New Words quest n. search extraterrestrial a. (coming from) outside the earth ponder v. think about slowly and carefully muse v. think deeply, forgetting about the world around one contemplate v. look at or think about intently; have in mind as a possibility or plan exotic a. not native; fascinating because strange or different 外国的;异国情调的 biology n. the scientific study of living things; animal and plant life, as of a given area 生物学;一个地区的生物 cosmic a. of the universe, esp. the heavens as distinguished from the earth 宇宙的 exquisite a. extremely beautiful or pleasant, esp. in a delicate or refined way acceptable a. good enough; satisfactory extraordinary a. very remarkable; exceptional unimaginably a. in an unimaginable manner; inconceivably astronomy n. the scientific study of the stars, planets, and other natural objects in space 天文学 array n. collection; an impressive display of numerous persons or objects 列阵 detector n. an instrument for discovering the presence of sth. dedicated vt. devoted dedicate vt. set apart for a special use or purpose operationally ad. in respect to operation operational a. galaxy n. any of the large groups of stars which make up the universe 星系 the Milky Way Galaxy 系 assign vt. fix; decide on quantity n. an amount or number abundance n. a great quantity; plenty planetary a. of a planet; having sth. to do with planets likelihood n. the degree to which sth. can reasonably be expected to happen; probability probability n. the condition of being likely to happen characteristically ad. in a characteristic manner characteristic n. a special feature or quality that makes sb. or sth. different from others a. showing a special feature or identity breathtakingly ad. astonishingly exhilarating a. very exciting; causing happiness diversity n. difference; variety diverse a. lifestyle n. a way of living commerce n. the buying and selling of goods; trade 商业 candidate n. a person or thing that is regarded as being suitable for a particular purpose or as being likely to do or be a particular thing Article/200802/26346蚌山区妇幼保健人民中医院激光去红血丝多少钱Bedtime Prayers   Julie was saying her bedtime prayers. "Please God," she said, "Make Naples the capital of Italy. Make Naples the capital of Italy."   Her mother interrupted and said, "Julie, why do you want God to make Naples the capital of Italy?"   And Julie replied, "Because that’s what I put in my geography exam!"   睡前祷告词   朱莉叶在做睡前祷告。“祷告上帝,”她说,“让那不勒斯成为意大利的首都吧。让那不勒斯成为意大利的首都吧。”   妈妈打断她说:“朱莉叶,你为什么求上帝让那不勒斯成为意大利的首都呢?”   朱莉叶回答说:“因为我在地理考卷上是这么写的。”   NOTE   bedtime prayers睡前祷告   Make Naples the capital of Italy让那不勒斯成为意大利的首都吧   Make + do sth是使什么什么怎么样的意思 Article/200802/26490台湾籍旅美老师今天交给我们的句子是:The second most common cause of fatigue comes from lack of physical activity and a poor diet. Study after study finds that adults who began light exercise a few times a week reported more energy after six weeks. People who exercise more regularly also report sleeping better. Even though studies show that they aren#39;t sleeping any longer.导致疲劳的第二常见原因便是动得不够和饮食不当。从多项研究中接连发现:若让成年人开始每周做几次的轻度运动,在持续6周后,他们明显变得更有精神,而较常规律运动的人也表示他们睡得比较好,即使研究显示:这些人的睡眠时间并没有比较长。学习重点:1.fatigue 疲劳、劳累fatigue (n.) 疲劳、劳累2.activity 活动activity (n.) 活动active (adj.) 活跃的3.diet 饮食、食物diet (n.) 饮食、食物4.regularly 有规律的regularly (adj.) 有规律的regular (adj.) 规则的 /201706/515153宿州市第一人民医院瘦腿针多少钱

蚌埠抽脂蚌埠哪家整形医院做双眼皮好的每天一个生活口语话题,一段地道的举例回答,并附有详细的词汇,发音及用法讲解。讲解材料选自当今最先进最有效的英语原版教材,更加贴近生活。每天坚持听讲解,并根据问题练习,给自己一个地道输入和输出的机会,你也可以张口自信说英语。主题:What does your name mean?Well, my last name is Zhang. That’s what I get from my dad. And my first name is Weijie. Wei means uniqueness, and Jie is the name of a very wise woman in ancient China. My granddad gave me this name, hoping that I could grow up to be a talented and special woman.Uniqueness: 唯一Wise:聪明Ancient:古代Talented:有才华的 /201612/485928Is there any other business?还有别的事吗?讲解:这句话的语气不是很友好,所以要慎用。 /201506/381444淮南市第一人民医院激光祛太田痣多少钱台湾籍旅美老师今天交给我们的句子是:The 2016 election has proven to be one of the most unexpected and divided elections in recent history. But outside of the ed States, there seems to be less of a divide over the two candidates, and more of a surprise at the overall state of affairs in the ed States.2016年美国总统大选的结果是美国近几次总统选举中最出乎意料、也最分歧的一场选举。但在美国之外的其他国家,对这两位总统候选人的看法似乎较无异议,反而是对美国整体局势较为讶异。学习重点:1.election 选举election (n.) 选举elect (v.) 选举2.proven 被明的proven (adj.) 被明的prove (v.) 明proof (n.) 据3.divide 分、划分divide (v.) 分、划分4.recent 最近的recent (adj.) 最近的recently (adv.) 最近decent (adj.) 正派的5.candidate 候选人candidate (n.) 候选人6.affair 事件、风流韵事affair (n.) 事件、风流韵事fair (adj.) 公正的 /201611/477082蚌埠市治疗青春痘多少钱

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