VOA标准英语2010-Expanding the Search for Extraterrestrial

Radio telescopes are not enough, says SETI scientist

Art Chimes | Washington, DC 16 April 2010

When the search for extra-terrestrial life began a half-century ago, it was assumed that technological¹ civilizations would broadcast more and more signals into space. But that assumption could be wrong.

Related Links
"The Eerie² Silence" (publisher's website)

"After 50 years of silence ... I'm trying to urge the SETI community to change their tactics a bit." — Paul Davies

 

Fifty years ago this week, a young Cornell University scientist named Frank Drake pointed³ a radio telescope at a distant star, hoping to hear transmissions from an alien civilization.

After a half-century, the search for extra-terrestrial intelligence, or SETI, has pretty much come up empty. But a leader in the SETI community says maybe we're looking in the wrong way.

New approach

When the search began, a half-century ago, it seemed sensible to assume that as technological civilization increased on a planet, more and more signals would be broadcast into space. It was just a matter of knowing where and how to tune⁴ in.

Now, it seems sensible to assume that that assumption could be wrong. Television and radio transmitters on Earth may soon go dark, replaced by cable, fiber⁵, satellites, and the Internet.

 

'The Eerie Silence,' reviews the search for alien life and suggests ways to broaden the quest.

So Arizona State University physicist⁶ and astrobiologist Paul Davies says we might not be hearing alien civilizations because they have transcended⁷ their broadcasting stage. And, as for sending a message aimed at us, Davies says they probably don't even know we're here.

'10,000 communicating civilizations in the galaxy⁸'

"Even an optimist⁹ like Frank Drake estimates that there would be no more than about 10,000 communicating civilizations in the galaxy, which means that the nearest one is likely to be about 1,000 light years away," he said in a VOA interview.

"Now, if you're on a star about 1,000 light years away, you see earth as it was 1,000 years ago. There were no radio telescopes. There was no radio technology here. It would make no point in those aliens sending messages our way at this particular time."

Eerie silence

Davies is the author of a new book, "The Eerie Silence," which reviews the search for alien life and suggests ways to broaden the quest.

He's not against the radio telescope surveys that have been the mainstay of SETI for the past 50 years, but he says maybe we're looking for the wrong thing.

"We could look for beacons," he suggests. "It could be that there are alien civilizations that have simply created something a little bit like a lighthouse that sweeps the plane of the galaxy, goes bleep, and it's there to attract attention, or it's a monument, or an aesthetic¹⁰ symbol or even a religious symbol. Who knows?  And that's a different type of search. I'm trying to urge the SETI community to change their tactics a bit."

Changing tactics

Or maybe, instead of a radio signal, an alien civilization sent us something physical. Science fiction writer Arthur C. Clarke described an object left on the moon to let aliens know when humans were able to travel in space. Davies says maybe aliens have sent a probe to orbit the Sun.

A more intriguing¹¹ possibility is that our genetic¹² makeup¹³ includes a signal encoded by aliens in our DNA¹⁴ that might have been left hundreds of millions of years ago.

"We have genes¹⁵ inside our body that go back three billion years, largely unchanged. So if you can somehow upload a message into DNA of terrestrial organisms, it could last a very, very long time, indeed."

Paul Davies admits some of his ideas may be "fanciful."

"But they illustrate¹⁶ what I want to try to do in this book, which is to just broaden the thinking to get away from this traditional sort of radio search. That should carry on, of course. But in addition, we need some new thinking. After 50 years of silence, I think the time has come to take stock and say, maybe we should mobilize all of the sciences to look for anything fishy¹⁷, anything weird¹⁸, any anomaly, both in our own little corner of the universe here on Earth and in the solar system, and far out across the galaxy." 

University of Arizona scientist Paul Davies' new book, "The Eerie Silence," advocates an expanded search for extra-terrestrial intelligence.

 

1 technological   

adj.技术的；工艺的

参考例句：

• A successful company must keep up with the pace of technological change.一家成功的公司必须得跟上技术变革的步伐。
• Today,the pace of life is increasing with technological advancements.当今， 随着科技进步，生活节奏不断增快。

2 eerie   

adj.怪诞的；奇异的；可怕的；胆怯的

参考例句：

• It's eerie to walk through a dark wood at night.夜晚在漆黑的森林中行走很是恐怖。
• I walked down the eerie dark path.我走在那条漆黑恐怖的小路上。

3 pointed   

adj.尖的，直截了当的

参考例句：

• He gave me a very sharp pointed pencil.他给我一支削得非常尖的铅笔。
• She wished to show Mrs.John Dashwood by this pointed invitation to her brother.她想通过对达茨伍德夫人提出直截了当的邀请向她的哥哥表示出来。

4 tune   

n.调子；和谐，协调；v.调音，调节，调整

参考例句：

• He'd written a tune,and played it to us on the piano.他写了一段曲子，并在钢琴上弹给我们听。
• The boy beat out a tune on a tin can.那男孩在易拉罐上敲出一首曲子。

5 fiber   

n.纤维，纤维质

参考例句：

• The basic structural unit of yarn is the fiber.纤维是纱的基本结构单元。
• The material must be free of fiber clumps.这种材料必须无纤维块。

6 physicist   

n.物理学家，研究物理学的人

参考例句：

• He is a physicist of the first rank.他是一流的物理学家。
• The successful physicist never puts on airs.这位卓有成就的物理学家从不摆架子。

7 transcended   

超出或超越（经验、信念、描写能力等）的范围( transcend的过去式和过去分词 )； 优于或胜过…

参考例句：

• He wanted assurance that he had transcended what was inherently ambiguous. 他要证明，他已经超越了本来就是混淆不清的事情。
• It transcended site to speak to universal human concerns. 它超越了场所的局限，表达了人类共同的心声。

8 galaxy   

n.星系；银河系；一群(杰出或著名的人物)

参考例句：

• The earth is one of the planets in the Galaxy.地球是银河系中的星球之一。
• The company has a galaxy of talent.该公司拥有一批优秀的人才。

9 optimist   

n.乐观的人，乐观主义者

参考例句：

• We are optimist and realist.我们是乐观主义者，又是现实主义者。
• Peter,ever the optimist,said things were bound to improve.一向乐观的皮特说，事情必定是会好转的。

10 aesthetic   

adj.美学的，审美的，有美感

参考例句：

• My aesthetic standards are quite different from his.我的审美标准与他的大不相同。
• The professor advanced a new aesthetic theory.那位教授提出了新的美学理论。

11 intriguing   

adj.有趣的；迷人的v.搞阴谋诡计(intrigue的现在分词)；激起…的好奇心

参考例句：

• These discoveries raise intriguing questions. 这些发现带来了非常有趣的问题。
• It all sounds very intriguing. 这些听起来都很有趣。 来自《简明英汉词典》

12 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

13 makeup   

n.组织；性格；化装品

参考例句：

• Those who failed the exam take a makeup exam.这次考试不及格的人必须参加补考。
• Do you think her beauty could makeup for her stupidity?你认为她的美丽能弥补她的愚蠢吗？

14 DNA   

(缩)deoxyribonucleic acid 脱氧核糖核酸

参考例句：

• DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
• Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

15 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪

16 illustrate   

v.举例说明，阐明；图解，加插图

参考例句：

• The company's bank statements illustrate its success.这家公司的银行报表说明了它的成功。
• This diagram will illustrate what I mean.这个图表可说明我的意思。

17 fishy   

adj. 值得怀疑的

参考例句：

• It all sounds very fishy to me.所有这些在我听起来都很可疑。
• There was definitely something fishy going on.肯定当时有可疑的事情在进行中。

18 weird   

adj.古怪的，离奇的；怪诞的，神秘而可怕的

参考例句：

• From his weird behaviour,he seems a bit of an oddity.从他不寻常的行为看来，他好像有点怪。
• His weird clothes really gas me.他的怪衣裳简直笑死人。