Part I
Professor: Last week, we covered some arguments against going back to the Moon. But there are compelling reasons in favor of another Moon landing too, um… not the least of which is trying to pinpoint the moon’s age. We could do this in theory by studying an enormous impact crater, known as the South Pole-Aitken Basin. Um…it’s located in the moon’s South Polar Region. But, since it’s on the far side of the moon, it can only be seen from space.
Here is an image of… we’ll call it the SPA Basin. This color-coated image of the SPA Basin, those aren’t its actual colors obviously, this image is from the mid-90s, from the American spacecraft called Clementine. Um… unlike earlier lunar missions, Clementine didn’t orbit only around the moon’s equator. Its orbits enabled it to send back data to create this topographical map of … well, the grey and white area towards the bottom is the South Pole, the purples and blues in the middle correspond to low elevations-the SPA Basin itself, the oranges and reds around it are higher elevations.
它的运行轨道使它可以发回数据创制这张地形图……嗯，图上底部的灰色和白色区域是南极，中间的紫色和蓝色区域对应着低海拔地区——SPA 盆地本身，橙色和 它周围的红色区域是更高海拔的地区。
1. compelling |kəmˈpelɪŋ|
adj. that makes you think it is true 令人信服的
E.g.: There is no compelling reason to believe him.
没有令人信服的理由让人相信他。
2. the least of
something of the lowest importance, strength, value, etc. 最不重要；最弱
E.g.: We had many things to consider, not the least of which was the safety of our children.
我们有很多事情要考虑，其中最重要的是我们孩子的安全。。
3. pinpoint |ˈpɪnpɔɪnt|
verb. to find and show the exact position of sb/sth or the exact time that sth happened 明确指出，确定（位置或时间）
E.g.: He was able to pinpoint on the map the site of the medieval village.
他能在地图上准确找出那个中世纪村庄的位置。
4. impact crater
An impact crater is an approximately circular depression in the surface of a planet, moon, or other solid body in the Solar System or elsewhere, formed by the hypervelocityimpact of a smaller body. 撞击坑，又称陨石坑或环形山为行星、卫星、小行星或其它类地天体表面通过陨石撞击而形成的环形的凹坑。撞击坑的中心往往会有一座小山，在地球上撞击坑内常常会积水，形成撞击湖，湖心则有一座小岛。
5. basin |ˈbeɪsn|
noun. a place where the earth's surface is lower than in other areas of the world 盆地；凹地；海盆
E.g.: the Pacific Basin
太平洋海盆
6. far |fɑ:(r)|
adj. at a greater distance away from you (同一处的两物)离得较远的，那一边的
E.g.: A narrow steep path leads down into a valley and up the far side.
一条狭窄陡峭的小径向下伸进山谷，又从山谷的那一边向上延伸。
7. coat |koʊt|
verb. to cover sth with a layer of a substance 给…涂上一层；（用…）覆盖
E.g.: cookies thickly coated with chocolate
外面涂有厚厚一层巧克力的曲奇
8. orbit |ˈɔ:rbɪt|
verb. to move in an orbit (= a curved path) around a much larger object, especially a planet, star, etc. 沿轨道运行；围绕…运动
E.g.: The earth takes a year to orbit the sun.
地球绕太阳一周要一年的时间。
9. correspond |ˌkɒrəˈspɒnd|
verb. to be similar to or the same as sth else 类似于；相当于
E.g.: The British job of Lecturer corresponds roughly to the US Associate Professor.
英国的讲师职位大致相当于美国的副教授。
10. elevation |ˌelɪˈveɪʃn|
noun. the height of a place, especially its height above sea level （某地方的）高度；（尤指）海拔
E.g.: The city is at an elevation of 2 000 metres.
这座城市海拔2 000米。
Part II
The basin measures an amazing 2,500 kilometers in diameter, and its average depth is 12 kilometers. That makes it the biggest known crater in our solar system and it may well be the oldest. You know planetary researchers love studying deep craters to learn about the impacts that created them, how they redistributed pieces of the planet’s crust.
And in this case, we especially want to know if any of the mantle, the layer beneath the crust, was exposed by the impact. Not everyone agrees, but some experts are convinced that whatever created the SPA Basin did penetrate the Moon’s mantle. And we need to find out, because much more than the crust, the mantle contains information about a planet’s or Moon’s total composition. And that’s key to understanding planet formation. Um… Dian?
Student: So, the only way to know the basin’s age is to study its rocks directly?
虽然不是所有人都同意，但有些专家相信，无论是什么东西造成了SPA 盆地，它也确实穿透了月球的地幔。
1. measure |ˈmeʒə(r)|
verb. to be a particular size, length, amount, etc. （指尺寸、长短、数量等）量度为
E.g.: The pond measures about 2 metres across.
这个池塘宽约2米。
2. crust|krʌst|
noun. a hard layer or surface, especially above or around sth soft or liquid （尤指软物或液体上面、周围的）硬层，硬表面
E.g.: the earth's crust
地壳
3. mantle |ˈmæntl|
noun. the part of the earth below the crust and surrounding the core 地幔
E.g.: The earth has a core and a mantle around it.
地球的中心是地核，地核的周围是地幔。
4. composition |ˌkɒmpəˈzɪʃn|
noun. the different parts which sth is made of; the way in which the different parts are organized 成分；构成；组合方式
E.g.: the chemical composition of the soil
土壤的化学成分
Part III
Professor: Well, from radio survey data, we know that the basin contains lots of smaller craters. So it must be really old, about 4 billion years, give or take a few hundred million years. But that’s not very precise. If we had rock samples to study, we’d know whether these small craters were formed by impacts during the final stages of planetary formation, or if they resulted from later meteor showers.
Student: But if we know around how old the Basin is, I’m not sure that’s reason enough to go to the Moon again.
Professor: No…, but such crude estimates… um… we can do better than that. Besides, there’s other things worth investigating, like is there water ice on the moon? Clementine’s data indicated that the wall of the south-polar crater was more reflective than expected. So some experts think there’s probably ice there.
Clementine的数据表明，南极陨石坑的坑壁比预期的更具有反射性。所以一些专家认为那里可能有冰。
1. give or take |lɒnˈdʒevəti|
if sth is correct give or take a particular amount, it is approximately correct 相差不到；出入至多
E.g.: It'll take about three weeks, give or take a day or so.
这要花大约三周时间，出入不过一天左右。
2. meteor shower
a transient shower of meteors when a meteor swarm enters the earth's atmosphere 流星雨
E.g.: Meteor shower is the most romantic and magnificently astronomical phenomena.
流星雨是最富浪漫色彩的天象奇观。
3. crude |kru:d|
adj. simple and not very accurate but giving a general idea of sth 粗略的；简略的；大概的
E.g.: In crude terms , the causes of mental illness seem to be of three main kinds.
简略地说，导致精神病的原因看起来主要有三种。
4. reflective |rɪˈflektɪv|
adj. reflective surfaces send back light or heat （指物体表面）反射热的，反光的
E.g.: On dark nights children should wear reflective clothing.
在漆黑的夜晚，儿童应该穿可以反光的衣服。
Part IV
Also, data from a later mission indicates significant concentrations of hydrogen and by inference water, less than a meter underground at both poles.
Student: Well, if there’s water, how did it get there? Underground rivers?
Professor: We think meteors that crashed into the moon or tails of passing comets may have introduced water molecules. Any water molecules that found their way to the floors of craters near the moon’s poles, that water would be perpetually frozen, because the floors of those craters are always in shadow. Um…furthermore, if the water ice was mixed in with rock and dust, it would be protected from evaporation.
Student: So are you saying there might be primitive life on the moon?
任何到达月球两极附近陨石坑底部的水分子都会被永久冻结，因为这些陨石坑的底部总是处在阴影中。
1. inference |ˈɪnfərəns|
noun. the act or process of forming an opinion, based on what you already know 推断；推理；推论
E.g.: If he is guilty then, by inference , so is his wife (= it is logical to think so, from the same evidence) .
如果他有罪，那么由此可以推断他的妻子也同样有罪。
2. introduce|ˌɪntrəˈdju:s|
verb. (formal) to put sth into sth 将…放进；添入
E.g.: Particles of glass had been introduced into the baby food.
这种婴儿食品中被掺进了玻璃碎屑。
3. perpetual |pəˈpetʃuəl|
adj. continuing for a long period of time without interruption 不间断的；持续的；长久的
E.g.: We lived for years in a perpetual state of fear.
多年来我们一直生活在恐惧中。
4. evaporate |ɪˈvæpəreɪt|
verb. if a liquid evaporates or if sth evaporates it, it changes into a gas, especially steam （使）蒸发，挥发
E.g.: The sun is constantly evaporating the earth's moisture.
太阳使地球上的湿气不断蒸发。
Part V
Professor: That’s not my point at all. Um… OK, say there is water ice on the moon. That would be of very practical value for a future moon base for astronauts. Water ice could be melted and purified for drinking. It could also be broken down into its component parts - oxygen and hydrogen. Oxygen could be used to breathe, and hydrogen could be turned into fuel, rocket fuel. So water ice could enable the creation of a self-sustaining moon base someday, a mining camp perhaps or a departure point for further space exploration.
Student: But hauling tons of equipment to the moon to make fuel and build a life support system for a moon base, wouldn’t that be too expensive?
Professor: Permanent base, maybe a ways off, but we shouldn’t have to wait for that. The dust at the bottom of the SPA Basin really does have a fascinating story to tell,what I wouldn’t give for a few samples of it.
因此，有朝一日，水冰可以支持建立一个自给自足的月球基地，一个采矿营地，或者一个可以进行进一步太空探索的出发站点。
1. purify|ˈpjʊərɪfaɪ|
verb. to make sth pure by removing substances that are dirty, harmful or not wanted 使（某物）洁净；净化
E.g.: One tablet will purify a litre of water.
一丸即可净化一升水。
2. self-sustaining|ˌsɛlfsəˈstenɪŋ|
adj. a self-sustaining process or system is able to continue by itself without anyone or anything else becoming involved （过程、体制）自我运行的，自我维持的
E.g.: Biologists say the area might be large enough to support a self-sustaining population.
生物学家称这个地区的面积可能足以让一个自我维系的种群生存下来。
3. haul |hɔ:l|
verb. to pull sth/sb with a lot of effort （用力）拖，拉，拽
E.g.: He reached down and hauled Liz up onto the wall.
他俯身把利兹拉上墙头。
4. ways|ˈweɪz|
noun. (US. informal) a distance 一段距离
E.g.: The wedding is still a long ways off. [=it is still far in the future]
婚礼还有很长的路要走。[=未来还很遥远]
5. what I wouldn't give for
used to say that you want something very much非常想要得到某物
E.g.: What I wouldn't give for a cold drink!
我十分想喝一杯冷饮。
10个月宝宝每天需要喝多少奶粉？
