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VOA慢速英语2012 EXPLORATIONS - A Vacuum Cleaner for Destroying Space Junk

时间:2012-04-05 05:55:34

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(单词翻译)

EXPLORATIONS - A Vacuum Cleaner for Destroying Space Junk

 
JIM TEDDER1: I’m Jim Tedder.
CHRISTOPHER CRUISE2: And I’m Christpher Cruise with EXPLORATIONS in VOA Special English. Today, we tell about an effort to destroy unused spacecraft and other objects floating high above the Earth. We also have news about SETI -- the Search for Extraterrestrial Intelligence.
(MUSIC)
JIM TEDDER: It just may be the world’s most costly3 vacuum cleaner. The price of CleanSpace One is eleven million dollars. But yet, it has a big job to do. Recently, researchers in Switzerland announced plans to build this new cleaning device. The researchers work at the Federal Institute of Technology in Lausanne.
CleanSpace One will not be for use in homes or businesses. It will be shot into space to help remove the thousands of pieces of space junk floating around up there.
CHRISTOPHER CRUISE: Last year, we reported on the problem of space junk. Over time, many unused spacecraft have hit each other far above the Earth. Big pieces break into thousands of small pieces. Sometimes they fall back into the atmosphere and burn up. But when they do not, it creates big problems.
Scientists fear that if something is not done to remove these objects, it may soon become too dangerous to send people and machines into space. There is a large chance that they might crash into some of this junk. So that is why the Swiss researchers are developing the new device.
JIM TEDDER: CleanSpace One is not really a vacuum cleaner. It will not be used to take away space junk. But scientists plan to move it close to an old satellite that is no longer being used. Then a claw-like instrument will seize the satellite, and force it back through the atmosphere. There, the satellite will be destroyed by the heat of friction4 with the air.
Researchers say that all they need to do is slow down the speed of some of these unwanted objects. Once these items begin to move more slowly, they will fall back to Earth. There is little chance that they will fall through the atmosphere and harm the people or things below. Some space junk has returned to Earth, but it usually causes no harm as it falls into the ocean.
CHRISTOPHER CRUISE: The American space agency NASA and scientific organizations in other countries know that space junk is a serious problem. They are tracking the movement of over twenty thousand unwanted items circling the Earth. Some people have suggested using lasers to push the items into a lower and slower orbit.
NASA recently gave money to a South Carolina company that hopes to make a device called Eddy5. That is the short name for ElectroDynamic Debris6 Eliminator. Eddy would work like the Swiss space cleaner. But it would use a net to catch an old satellite like a fish before sending it back through the atmosphere.
JIM TEDDER: John L. Junkins is an aerospace7 engineer with Texas A and M University. He says we need to remove five or six large space objects each year to stop what he calls the cascading8 effect. That is what happens when large objects, some as big as a bus, crash together. When they break apart, they create thousands of smaller parts that continue floating around the Earth. Professor Junkins says we would need to remove ten large pieces of space junk each year to stop the damage they might cause.
(MUSIC)
CHRISTOPHER CRUISE: While some scientists are watching things circling the Earth, others are searching the sky for something that is not made by humans. SETI -- the search for extraterrestrial intelligence -- is back on the job. But the question is: for how long? SETI has been searching the stars for nearly thirty years. But its scientists say the group has never had enough money. Last year, SETI suspended operations for a time. But the general public and some very wealthy people have given enough money to re-start the project.
JIM TEDDER: In February, SETI scientists began asking the public to help them with their research. The scientists are using a website to re-direct radio signals over the Internet. They have asked the public to use home computers, and their ears, to search for anything unusual. They hope the human brain can find things that their automated9 equipment cannot.
SETI’s telescopes and computers examine many different radio frequencies every day. But they ignore some frequencies because there are just too many radio signals in the air at any one time. The scientists hope that home computers will find an unusual sound “hidden” within sounds made by the technologies we use every day. In other words, they think that an alien radio signal might be covered up by the powerful signal of a local radio station.
CHRISTOPHER CRUISE: Much of SETI’s work involves the Allen Telescope Array10 -- over forty radio telescopes located in northeastern California. Scientists there point the circular antennas11 at an area of the sky called Cygnus. They are hoping to hear some signal or noise that is being sent into space by intelligent life. They hope to answer perhaps the biggest scientific question: are we alone in the universe? The area of the sky being searched seems large. But it really is a small part of the whole universe.
JIM TEDDER: For many years, researchers thought our solar system, the sun with Earth and the other planets, was a very special place. But that has changed. Researchers now believe there are billions of stars like our sun with planets orbiting around them. They also think that many of these planets are able to support life as we know it.
Long before SETI, an astronomer12 named Frank Drake began searching the skies for radio signals. In nineteen sixty, he worked at the National Radio Astronomy13 Observatory14 in West Virginia. He is almost sure that we are not alone. Using a mathematical model he created, he estimates that there are ten thousand places in our part of the universe where life exists.
(MUSIC)
CHRISTOPHER CRUISE: After looking at millions of stars and listening to radio noise for many years, have scientists ever found anything that suggests there is intelligent alien life? The answer is: maybe. It happened one night in nineteen seventy-seven. A large radio telescope in Ohio heard something that made the scientists say, “Wow.”
The telescope was connected to a computer and a printer. The gathered information usually showed a series of low numbers, ones, twos, and threes. That meant that all the device was hearing was low level "background” noise, similar to the sound you hear when you set your radio between stations. But suddenly, something surprising happened. For a little over one minute, the noise level rose to a level thirty times what was usually heard. For seventy-two seconds, it appeared to some that our distant space brothers and sisters had finally said, “Hello.” When Jerry Ehman, a SETI scientist saw what the printer had produced, he drew a circle on the page in red ink and wrote, “Wow.”
JIM TEDDER: But just as suddenly as the signal had started, it stopped. And it has never been found again. So, what was it? What might it have been? Those questions have been on the mind of Robert Gray for years. He is an astronomer who recently finished work on a book called “The Elusive15 Wow.” He says that the information gathered in Ohio in nineteen seventy-seven looks exactly like a radio signal. He also says it is not likely that an airplane or a satellite was the cause.
Mr. Gray found that the “Wow” signal was very close to the number of vibrations16 per second of hydrogen when it gives off light. Hydrogen is the most common element in the universe. So some scientists think an intelligent alien would use its “glow frequency” as a radio signal. But why did the signal suddenly appear and then just as quickly disappear?
CHRISTOPHER CRUISE: Robert Gray calls that the “lighthouse effect.” If you were on a ship at sea and saw a lighthouse beam in the distance, it would appear to come and go across the night sky. It would not stay in one place. Mr. Gray says that might describe what aliens would do. They would sweep a radio signal to different parts of the sky, rather than just send it to one place. That way it might be seen, or heard, by more telescopes in many different places.
Mr. Gray thinks that in a hundred years, scientists will have far better equipment to examine the distant stars. We might be able to look at the entire known universe at one time instead of just examining such a small part of it. That should increase the chances that we will hear from our distant neighbors -- if they are out there.
(MUSIC)
CHRISTOPHER CRUISE: I’m Christopher Cruise.
JIM TEDDER: And I’m Jim Tedder. 

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1 tedder 2833afc4f8252d8dc9f8cd73b24db55d     
n.(干草)翻晒者,翻晒机
参考例句:
  • Jim Tedder has more. 吉姆?特德将给我们做更多的介绍。 来自互联网
  • Jim Tedder tells us more. 吉姆?泰德给我们带来更详细的报道。 来自互联网
2 cruise 2nhzw     
v.巡航,航游,缓慢巡行;n.海上航游
参考例句:
  • They went on a cruise to Tenerife.他们乘船去特纳利夫岛。
  • She wants to cruise the canals of France in a barge.她想乘驳船游览法国的运河。
3 costly 7zXxh     
adj.昂贵的,价值高的,豪华的
参考例句:
  • It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
  • This dictionary is very useful,only it is a bit costly.这本词典很有用,左不过贵了些。
4 friction JQMzr     
n.摩擦,摩擦力
参考例句:
  • When Joan returned to work,the friction between them increased.琼回来工作后,他们之间的摩擦加剧了。
  • Friction acts on moving bodies and brings them to a stop.摩擦力作用于运动着的物体,并使其停止。
5 eddy 6kxzZ     
n.漩涡,涡流
参考例句:
  • The motor car disappeared in eddy of dust.汽车在一片扬尘的涡流中不见了。
  • In Taylor's picture,the eddy is the basic element of turbulence.在泰勒的描述里,旋涡是湍流的基本要素。
6 debris debris     
n.瓦砾堆,废墟,碎片
参考例句:
  • After the bombing there was a lot of debris everywhere.轰炸之后到处瓦砾成堆。
  • Bacteria sticks to food debris in the teeth,causing decay.细菌附着在牙缝中的食物残渣上,导致蛀牙。
7 aerospace CK2yf     
adj.航空的,宇宙航行的
参考例句:
  • The world's entire aerospace industry is feeling the chill winds of recession.全世界的航空航天工业都感受到了经济衰退的寒意。
  • Edward Murphy was an aerospace engineer for the US Army.爱德华·墨菲是一名美军的航宇工程师。
8 cascading 45d94545b0f0e2da398740dd24a26bfe     
流注( cascade的现在分词 ); 大量落下; 大量垂悬; 梯流
参考例句:
  • First of all, cascading menus are to be avoided at all costs. 首先,无论如何都要避免使用级联菜单。 来自About Face 3交互设计精髓
  • Her sounds began cascading gently. 他的声音开始缓缓地低落下来。
9 automated fybzf9     
a.自动化的
参考例句:
  • The entire manufacturing process has been automated. 整个生产过程已自动化。
  • Automated Highway System (AHS) is recently regarded as one subsystem of Intelligent Transport System (ITS). 近年来自动公路系统(Automated Highway System,AHS),作为智能运输系统的子系统之一越来越受到重视。
10 array ivez6     
n.展示,排列,盛装;vt.排列,打扮
参考例句:
  • He was unable to escape the array of facts.他无法躲避一连串的事实。
  • She puts on her finest array.她穿上最漂亮的衣服。
11 antennas 69d2181fbb4566604480c825f4e01d29     
[生] 触角,触须(antenna的复数形式)
参考例句:
  • Marconi tied several antennas to kites. 马可尼在风筝上系了几根天线。 来自超越目标英语 第3册
  • Radio astronomy today is armed with the largest antennas in the world. 射电天文学拥有世界上最大的天线。
12 astronomer DOEyh     
n.天文学家
参考例句:
  • A new star attracted the notice of the astronomer.新发现的一颗星引起了那位天文学家的注意。
  • He is reputed to have been a good astronomer.他以一个优秀的天文学者闻名于世。
13 astronomy hOQyf     
n.天文学
参考例句:
  • Mathematics is connected with astronomy.数学与天文学有联系。
  • Astronomy is an abstract subject.天文学是一门深奥的学科。
14 observatory hRgzP     
n.天文台,气象台,瞭望台,观测台
参考例句:
  • Guy's house was close to the observatory.盖伊的房子离天文台很近。
  • Officials from Greenwich Observatory have the clock checked twice a day.格林威治天文台的职员们每天对大钟检查两次。
15 elusive d8vyH     
adj.难以表达(捉摸)的;令人困惑的;逃避的
参考例句:
  • Try to catch the elusive charm of the original in translation.翻译时设法把握住原文中难以捉摸的风韵。
  • Interpol have searched all the corners of the earth for the elusive hijackers.国际刑警组织已在世界各地搜查在逃的飞机劫持者。
16 vibrations d94a4ca3e6fa6302ae79121ffdf03b40     
n.摆动( vibration的名词复数 );震动;感受;(偏离平衡位置的)一次性往复振动
参考例句:
  • We could feel the vibrations from the trucks passing outside. 我们可以感到外面卡车经过时的颤动。
  • I am drawn to that girl; I get good vibrations from her. 我被那女孩吸引住了,她使我产生良好的感觉。 来自《简明英汉词典》

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