2006年VOA标准英语-US Shuttle Astronauts Test Orbital Repair Metho

By David McAlary
Washington
12 July 2006
 

Astronaut Mike Fossum (on arm)installs the International Space Station's railcar-like mobile transporter  
  
U.S. space shuttle astronauts are on their third spacewalk since Saturday, this time to practice methods of inspecting and repairing the vehicle's fragile shell in orbit. 

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The spacewalk is part of the U.S. space agency NASA's three-year effort to prevent the loss of another shuttle following the Columbia accident in 2003.  It has developed tools astronauts could use in orbit to inspect and fix the ceramic¹ tile and reinforced carbon skin that protects a shuttle against the searing heat of re-entry into Earth's atmosphere.

Columbia burned up when gases superheated by re-entry friction² entered a hole in its wing.  The puncture³ occurred at launch when hard foam⁴ insulation⁵ broke away from the external fuel tank.  Columbia's crew had no way of knowing about or filling the hole in space and perished as a result.

On today's spacewalk outside the shuttle Discovery, astronauts Piers⁶ Sellers and Mike Fossum are testing two techniques that NASA hopes would avoid such a catastrophe⁷.

"Our number one goal is to never have to use them," Ceccacci says.

Tony Ceccacci is the lead flight director for Discovery, which is docked at the International Space Station on a resupply mission. 

He says one new tool the spacewalkers are evaluating is a heat-sensing infrared⁸ camera designed to detect invisible damage to the reinforced carbon panels that cover the leading edges of shuttle wings.  The camera can record subtle temperature differences that would indicate the presence of a crack.

"Their hope is this is another sensor⁹ that will help us detect damage and minimize the impacts that we have to a mission," Ceccacci says.

Astronauts Fossum and Sellers are also testing a way to patch cracks.  They are using caulking¹⁰ guns and putty knives to apply a black paste the consistency¹¹ of peanut butter to samples of damaged wing panels.  Ceccacci says it is expected to seal cracks up to 10 centimeters long, but not large holes.

"I do not think that is going to repair every piece of damage or everything that we would see on the vehicle, but it may give us an idea that at least I have something in my toolbox that I can use," Ceccacci says.

NASA has already equipped the robot arms on shuttles with a boom extension that holds a camera and sensors¹² to inspect the underside of the orbiters during a flight.  Astronauts Fossum and Sellers bounced around on it during their first spacewalk Saturday and found it stable enough to use as a platform on which to make orbital repairs.  

NASA says if Discovery's mission is successful, it will launch another shuttle next month to resume space station construction for the first time since Columbia's demise¹³.  

1 ceramic   

n.制陶业，陶器，陶瓷工艺

参考例句：

• The order for ceramic tiles has been booked in.瓷砖的订单已登记下来了。
• Some ceramic works of art are shown in this exhibition.这次展览会上展出了一些陶瓷艺术品。

2 friction   

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。

3 puncture   

n.刺孔，穿孔；v.刺穿，刺破

参考例句：

• Failure did not puncture my confidence.失败并没有挫伤我的信心。
• My bicycle had a puncture and needed patching up.我的自行车胎扎了个洞，需要修补。

4 foam   

v./n.泡沫，起泡沫

参考例句：

• The glass of beer was mostly foam.这杯啤酒大部分是泡沫。
• The surface of the water is full of foam.水面都是泡沫。

5 insulation   

n.隔离；绝缘；隔热

参考例句：

• Please examine the insulation of the electric wires in my house.请检查一下我屋子里电线的绝缘情况。
• It is always difficult to assure good insulation between the electric leads.要保证两个电触头之间有良好的绝缘总是很困难的。

6 piers   

n.水上平台( pier的名词复数 )；（常设有娱乐场所的）突堤；柱子；墙墩

参考例句：

• Most road bridges have piers rising out of the vally. 很多公路桥的桥墩是从河谷里建造起来的。 来自辞典例句
• At these piers coasters and landing-craft would be able to discharge at all states of tide. 沿岸航行的海船和登陆艇，不论潮汐如何涨落，都能在这种码头上卸载。 来自辞典例句

7 catastrophe   

n.大灾难，大祸

参考例句：

• I owe it to you that I survived the catastrophe.亏得你我才大难不死。
• This is a catastrophe beyond human control.这是一场人类无法控制的灾难。

8 infrared   

adj./n.红外线(的)

参考例句：

• Infrared is widely used in industry and medical science.红外线广泛应用于工业和医学科学。
• Infrared radiation has wavelengths longer than those of visible light.红外辐射的波长比可见光的波长长。

9 sensor   

n.传感器，探测设备，感觉器（官）

参考例句：

• The temperature sensor is enclosed in a protective well.温度传感器密封在保护套管中。
• He plugged the sensor into a outlet.他把传感器插进电源插座。

10 caulking   

n.堵缝；敛缝；捻缝；压紧v.堵（船的）缝( caulk的现在分词 )；泥…的缝；填塞；使不漏水

参考例句：

• Plumbers caulk joints in pipe with lead,string or a caulking compound. 管子工用铅、绳子或专用填隙材料使管子的接头不漏水。 来自辞典例句
• Older windows and doors require maintenance -- scraping, painting and caulking. 旧门窗需要一系列维护，诸如，刮磨，上漆，勾缝。 来自互联网

11 consistency   

n.一贯性，前后一致，稳定性；(液体的)浓度

参考例句：

• Your behaviour lacks consistency.你的行为缺乏一贯性。
• We appreciate the consistency and stability in China and in Chinese politics.我们赞赏中国及其政策的连续性和稳定性。

12 sensors   

n.传感器，灵敏元件( sensor的名词复数 )

参考例句：

• There were more than 2000 sensors here. 这里装有两千多个灵敏元件。 来自《简明英汉词典》
• Significant changes have been noted where sensors were exposed to trichloride. 当传感器暴露在三氯化物中时，有很大变化。 来自辞典例句

13 demise   

n.死亡；v.让渡，遗赠，转让

参考例句：

• He praised the union's aims but predicted its early demise.他赞扬协会的目标，但预期这一协会很快会消亡。
• The war brought about the industry's sudden demise.战争道致这个行业就这么突然垮了。