英语听力：自然百科 地球力场 Earth's Force Field—18

 Earth's magnetic field has reversed thousands of times since its formation 4.5 billion years ago. And scientists now believe that the next reversal is imminent¹. The race is on to predicting exactly when it will occur. In 2010, the European Space Agency will launch SWARM². Its mission is to generate accurate, up-to-the-minute maps of the Earth's magnetosphere and anticipate its future activity. Professor Nils Olsen of the Danish National Space Center is working on the mission. 

 

 

 

“Then you’ve had exciting idea behind SWARM is that we have three satellites. We have higher satellite at an altitude of 530 kilometers and we have a pair of satellites at an altitude of about 400 kilometers.”

 

 

 

These identical satellites are equipped with new generation magnetometers. These will detect minute variations and field strength as well as identifying any new areas where the poles are reversing. 

 

 

 

“I think it's amazing that we can take magnetic measurements by the satellites flying at a few hundred kilometers, and say something about the deepness into the earth how the molten iron moves at a depth of about 3,000 kilometers. Is that amazing?” 

 

 

 

Scientists hope these satellites will help them predict when the magnetic poles are about to switch. They might even save lives. 

 

 

 

“I think that in the next decade or two, we can develop a science to forecast where the Earth's magnetic field is headed, and use that then as a planning tool; use that as a planning tool for people who fly satellites; as a planning tool for people who fly manned spaceflight and develop the technologies necessary to deal with, but say, an impending³ reversal.”

 

1 imminent   

adj.即将发生的，临近的，逼近的

参考例句：

• The black clounds show that a storm is imminent.乌云预示暴风雨即将来临。
• The country is in imminent danger.国难当头。

2 swarm   

n.(昆虫)等一大群；vi.成群飞舞；蜂拥而入

参考例句：

• There is a swarm of bees in the tree.这树上有一窝蜜蜂。
• A swarm of ants are moving busily.一群蚂蚁正在忙碌地搬家。

3 impending   

a.imminent, about to come or happen

参考例句：

• Against a background of impending famine, heavy fighting took place. 即将发生饥荒之时，严重的战乱爆发了。
• The king convoke parliament to cope with the impending danger. 国王召开国会以应付迫近眉睫的危险。