英语听力文摘 English Digest 615、制造属于你自己的月球陨石坑

 　　Create Your Own Moon Craters²!

 

　　What makes science really fun is when you get to do things yourself, so today we’re going to be making moon craters.

 

　　They’re the roundish blast-marks left on the moon’s surface by ancient meteorites⁴. The moon’s surface is covered with literally⁵ billions of impact craters, and some of them are bigger than a fair-sized city on earth. You can see the bigger ones just with the naked eye, and with a pair of binoculars⁶ you can make out many more.

 

　　So now let’s make some of our own. Take a wide, flat pan, such as the kind you’d bake cookies in. Take it outside, because this gets kind of messy! Poor flour or baking soda⁷ or sand across the bottom so it makes a thick, flat surface. That’s your undisturbed moon.

 

　　Now have a young person drop rocks onto the moonscape. When it hits, the energy of the falling rock is transferred to the powdery surface, and voila! Impact crater¹. Instead of just doing it at random⁸, though, have your young person drop one rock from a height of two feet, another from four feet, and another from six feet. You’ll find that the craters change shape depending on the energy of the incoming meteorite³. Higher-energy impacts make wider craters, with debris⁹ shooting out from their centers in what are called “rays.” Smaller ones look like little volcanoes. Throwing a stone at an angle makes an oblong crater.

 

　　Afterward¹⁰, take a look at the moon again through binoculars when it rises. You may have a better sense of what all those pock-marks really are!

1 crater   

n.火山口，弹坑

参考例句：

• With a telescope you can see the huge crater of Ve-suvius.用望远镜你能看到巨大的维苏威火山口。
• They came to the lip of a dead crater.他们来到了一个死火山口。

2 craters   

n.火山口( crater的名词复数 )；弹坑等

参考例句：

• Small meteorites have left impact craters all over the planet's surface. 这个行星的表面布满了小块陨石留下的撞击坑。 来自《简明英汉词典》
• The battlefield was full of craters made by exploding shells. 战场上布满弹坑。 来自《现代英汉综合大词典》

3 meteorite   

n.陨石；流星

参考例句：

• The meteorite in Jilin Exhibition Hall is believed to be the largest in the world.吉林展览馆的陨石被认为是世界上最大的。
• The famous Murchison meteorite smashed into the Australian ground in 1969.1969年著名的默奇森陨石轰然坠落在澳大利亚。

4 meteorites   

n.陨星( meteorite的名词复数 )

参考例句：

• Small meteorites have left impact craters all over the planet's surface. 这个行星的表面布满了小块陨石留下的撞击坑。 来自《简明英汉词典》
• One theory about the existence of extraterrestrial life rests on the presence of carbon compounds in meteorites. 地球外存在生命的理论是基于陨星上存在碳化合物质这一事实的。 来自《简明英汉词典》

5 literally   

adv.照字面意义，逐字地；确实

参考例句：

• He translated the passage literally.他逐字逐句地翻译这段文字。
• Sometimes she would not sit down till she was literally faint.有时候，她不走到真正要昏厥了，决不肯坐下来。

6 binoculars   

n.双筒望远镜

参考例句：

• He watched the play through his binoculars.他用双筒望远镜看戏。
• If I had binoculars,I could see that comet clearly.如果我有望远镜，我就可以清楚地看见那颗彗星。

7 soda   

n.苏打水；汽水

参考例句：

• She doesn't enjoy drinking chocolate soda.她不喜欢喝巧克力汽水。
• I will freshen your drink with more soda and ice cubes.我给你的饮料重加一些苏打水和冰块。

8 random   

adj.随机的；任意的；n.偶然的(或随便的)行动

参考例句：

• The list is arranged in a random order.名单排列不分先后。
• On random inspection the meat was found to be bad.经抽查，发现肉变质了。

9 debris   

n.瓦砾堆，废墟，碎片

参考例句：

• After the bombing there was a lot of debris everywhere.轰炸之后到处瓦砾成堆。
• Bacteria sticks to food debris in the teeth,causing decay.细菌附着在牙缝中的食物残渣上，导致蛀牙。

10 afterward   

adv.后来；以后

参考例句：

• Let's go to the theatre first and eat afterward. 让我们先去看戏，然后吃饭。
• Afterward,the boy became a very famous artist.后来，这男孩成为一个很有名的艺术家。