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http://n1audio.hjfile.cn/mh/2017/02/09/69ed5498a957a98e48abcf97bdf048b9.mp3
文字稿
首个远征南极寻找铁陨石的英国科学考察组已获得开展探险的许可。收藏在世界各地的太空陨石大多是在南极大陆上捡到的。覆盖该地区的白色冰层使搜寻这些黑色残留物的任务变得格外有成效。但是含铁的陨石却很少在南极大陆上被发现，其中有何奥妙吗？请听Jonathan Amos 的报道。
It's a mystery that's long puzzled scientists. Why are so few iron meteorites picked up off the ice of Antarctica? They must fall evenly across the earth, but desert regions, for example, yield ten times as many lumps of space metal.
Now Manchester University mathematicians think they have the answer. Their studies indicate these iron-rich rocks have a trick to hide away from collectors. Because the rocks are made of metal, they are able to conduct the heat of the sun very efficiently to their undersides. This melts the surrounding ice, enabling them to sink downwards and out of sight.
The Manchester team has just won funding to go test its idea and plans to find the missing meteorites and dig them up with the aid of landmine detection technology.
词汇表
iron meteorites 陨铁，铁陨石
picked up 被捡起，被拿走
desert regions 沙漠地区
yield 给出、带来
lumps of 一块块（通常指形状不固定的坚硬物质）
iron-rich 含铁量高的
conduct 传导（热）
undersides 底部
out of sight 在视野之外，看不见
detection 探测
测验
请听报道并回答下列问题。
1. According to the text, what is the mystery that has puzzled scientists for a long time?
2. What technology does the Manchester team plan to use to find and dig up the missing meteorites?
3. True or false? The metal rocks are able to conduct the heat of the sun, which enables them to melt and sink downwards.
4. Which word in the text means 'in equal numbers or amounts'?
答案
1. According to the text, what is the mystery that has puzzled scientists for a long time?
The mystery that has long puzzled scientists is why so few iron meteorites are picked up off the ice of Antarctica.
2. What technology does the Manchester team plan to use to find and dig up the missing meteorites?
The Manchester team plans to find the missing meteorites and dig them up with the aid of landmine detection technology.
3. True or false? The metal rocks are able to conduct the heat of the sun, which enables them to melt and sink downwards.
False. The metal rocks are able to efficiently transfer heat to their undersides where they can melt the surrounding ice, and this allows them to sink downwards.
4. Which word in the text means 'in equal numbers or amounts'?
Evenly.
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发表于 2017-3-15 21:07:32