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What makes science really fun is when you get to do things yourself, so today we’re going to be making moon craters².
科学真正变得有趣的时刻就是当你亲自实践的时候，那么今天，让我们来一起制作月球陨石坑吧！

They’re the roundish blast-marks left on the moon’s surface by ancient meteorites³. 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.
陨石坑呈圆形，它们是古代陨石撞击月球表面所留下的痕迹。月球表面有着数以亿计的陨石坑，有的陨石坑比地球上一个大城市还要大。仅用肉眼你就能看到月球表面较大的陨石坑，如果使用望远镜的话，你可以看到更多陨石坑。

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.
那么现在就让我们来制作自己的陨石坑。找一个宽而平的平底锅，类似我们平时烤饼干所用的那种。最好到外面做这个实验，因为场面会变得十分狼藉。把面粉、小苏打或者是沙子倒在底部，形成一个厚实平坦的表面，这看起来就像是没受到过撞击的月球。

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 meteorite⁴. 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.
现在，找个年轻人往这个月球表面上扔石头。当石头击中表面时，石头落下时的动能就会在粉状的表面转化成撞击力，瞧！陨石坑就形成了。但是不要随意地从上往 下扔石头，让一个人先从两英尺的高度往下扔，然后再从四英尺的高度扔，接着是六英尺。你会发现陨石坑的大小跟陨石的动能有关。能量越大，形成的陨石坑就越 大。陨石坑中心受到撞击后会碎片四溅，就像是射线一般。较小的陨石坑看起来很像小火山。从任何一个角度扔石头都会形成一个椭圆形的陨石坑。

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!
以后，当月亮升起的时候，你再用望远镜看看它，就会对月球上的这些“麻子”有着更清晰的认识。