Question

It just may be the world’s most costly vacuum cleaner (吸尘器). The price of CleanSpace One is eleven million dollars. But yet, it has a big job to do. Recently, researchers in Switzerland said they planned to build this new cleaning machine.

CleanSpace One will not be for use in homes or businesses. It will be shot into space to help remove thousands of pieces of space junk floating around up there.

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 (大气层) 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 hit some of this junk. So that is why the Swiss researchers are developing the new machine.

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 catch the satellite, and force it back through the atmosphere. There, the satellite will be destroyed by the heat of friction (摩擦) with the air.

Researchers say that all they need to do is slow down the speed of some of these unwanted objects. Once they begin to move more slowly, they will fall back to the Earth. There is little chance that they will fall through the atmosphere and harm the people or things below.

1.Space junk is created when ____________.

A. unused spacecraft hit each other

B. people in space throw away rubbish

C. a new spaceship is sent up

D. an old spaceship creates friction with the air

2.What’s the danger of space junk?

A. It will pollute space.    B. It will hurt people on the Earth.

C. It will hit a spaceship.    D. It will burn in the atmosphere.

3.Unwanted objects will fall back to the Earth when _______ .

A. they are made to move slowly    B. they meet other objects in space

C. they are not used for years    D. they are near the atmosphere

Answer

1.A

2.C

3.A

【解析】本文讲述是如何销毁未使用的航天飞机和其他漂浮在地球上空的物体——太空垃圾。

1.A

细节理解题。根据第三段提到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 (大气层) and burn up. But when they do not, it creates big problems.随着时间的推移，许多未使用的航天飞机在地球上空互相撞击。大型碎块分解成数千快小型碎块，有时他们会回到大气层中并自然销毁，但在这个过程中将会造成大问题。故选A。

2.C

推理判断题。根据第四段提到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 hit some of this junk.科学家们担心，如果不能消除这些物体，发射载人航天飞机或卫星进入太空变得十分危险。他们将有很大机会撞击到一些太空垃圾。故选C。

3.A

细节理解题。根据最后一段提到Once they begin to move more slowly, they will fall back to the Earth. There is little chance that they will fall through the atmosphere and harm the people or things below.一旦这些东西开始缓慢移动，他们将回落到地球。有很小的几率，他们将降落并穿过大气层，伤害大气层下面的人或物体。根据句意可知选A。