英语听力：自然百科 地球力场 Earth's Force Field—12

 Six years later, they come to believe these light flashes are the results of high energy, heavy cosmic rays penetrating¹ the spacecraft and the crew members' eyes.

 

 

 

 

 

These/ protons or electrons, just very, very high energy, ripped / part of atoms, spring out from the sun. In terms of manned space travel, if you're outside the magnetosphere in a big solar storm, large amounts of radiation passing through your body, dire² / health consequences.

 

 

 

These particles can become trapped inside a region of the magnetosphere known as the Van Allen Belt. They present a real hazard to astronauts. At least 39 astronauts have developed some kind of eye cataract³, 4 or 5 years after exposure to this dangerous radiation. As our protective magnetic field weakens, the risk to life increases. 

 

 

 

Professor Gary Glatsmire wants to know how much weaker the Earth's magnetosphere is going to get. He creates a remarkable⁴ computer model of Earth's magnetic field.

 

 

 

We can't reproduce exactly what the Earth has done in the past or what it is doing right now. What we are trying to do is get the model to simulate something that's qualitatively⁵ similar.

 

 

 

Glatsmire runs the computer model continually. Each year of real time represents 100,000 years of simulated time. He observes how the magnetic field evolves over the millennia⁶. Around 36,000 years into the simulation, something unusual happens.

 

 

 

After I've been away for a couple of weeks, I came back and looked at the results and then realized that it had reversed, and it was exciting.

 

 

 

Glatsmire's experiment shows the magnetic North and magnetic South switch positions.

 

 

 

This is the surface of the model Earth, this is the surface of the model core. Field is directed inwards here and outwards⁷ there, field is much more complicated on the top of the core. Now the reversal is occurring, the field is now drifted outwards there and inwards there.

1 penetrating   

adj.（声音）响亮的，尖锐的adj.（气味）刺激的adj.（思想）敏锐的，有洞察力的

参考例句：

• He had an extraordinarily penetrating gaze. 他的目光有股异乎寻常的洞察力。
• He examined the man with a penetrating gaze. 他以锐利的目光仔细观察了那个人。

2 dire   

adj.可怕的，悲惨的，阴惨的，极端的

参考例句：

• There were dire warnings about the dangers of watching too much TV.曾经有人就看电视太多的危害性提出严重警告。
• We were indeed in dire straits.But we pulled through.那时我们的困难真是大极了，但是我们渡过了困难。

3 cataract   

n.大瀑布，奔流，洪水，白内障

参考例句：

• He is an elderly gentleman who had had a cataract operation.他是一位曾经动过白内障手术的老人。
• The way is blocked by the tall cataract.高悬的大瀑布挡住了去路。

4 remarkable   

adj.显著的，异常的，非凡的，值得注意的

参考例句：

• She has made remarkable headway in her writing skills.她在写作技巧方面有了长足进步。
• These cars are remarkable for the quietness of their engines.这些汽车因发动机没有噪音而不同凡响。

5 qualitatively   

质量上

参考例句：

• In other words, you are to analyze them quantitatively and qualitatively. 换句话说，你们要对它们进行量和质的分析。
• Electric charge may be detected qualitatively by sprinkling or blowing indicating powders. 静电荷可以用撒布指示粉剂的方法，予以探测。

6 millennia   

n.一千年，千禧年

参考例句：

• For two millennia, exogamy was a major transgression for Jews. 两千年来，异族通婚一直是犹太人的一大禁忌。
• In the course of millennia, the dinosaurs died out. 在几千年的时间里，恐龙逐渐死绝了。

7 outwards   

adj.外面的，公开的，向外的；adv.向外；n.外形

参考例句：

• Does this door open inwards or outwards?这门朝里开还是朝外开？
• In lapping up a fur,they always put the inner side outwards.卷毛皮时，他们总是让内层朝外。