经济学人35:微型汽车大的探测器在火星着陆

 　　Science and Technolgy

　　科技

　　Mars exploration

　　探测火星

　　How to land a Mini on Mars

　　如何让一辆微型汽车大的探测器在火星着陆

　　The biggest and fanciest Mars rover so far will soon blast off from Florida

　　迄今为止最昂贵、最大的火星漫游者将很快从佛罗里达发射升空

　　EARTH excepted, the most probed and prodded¹ planet in the solar system is Mars. Besides the assortment² of craft that have flown by it or gone into orbit around it, three robotic buggies equipped with cameras and scientific instruments have roamed the Martian surface on behalf of NASA, America's space agency, since 1997.

　　除了地球，火星是太阳系里被人类探索得最多、最让人感到刺激的行星。除了各种飞过它的以及进入它附近轨道的飞船外，从1997年开始，三个装配了相机和科学仪器的探险车已经代表美国太空机构NASA漫游了火星表面。

　　If all goes according to plan, they will soon be joined by a fourth. On November 26th a new rover, Curiosity, will ascend³ from Cape⁴ Canaveral. If it gets there in one piece, it will examine the climate and geology of Mars and look for any signs of life that might have arisen.

　　如果所有一切都按计划进行，第四个将探险车将很快加入其中。11月26日，新的漫游者"好奇号"将从卡拉维拉尔角发射升空。如果它完好无损地抵达，它将考察火星气候和地质，并寻找可能出现的生命迹象。

　　The first of NASA's rovers, Sojourner⁵, which reached Mars in 1997, was 65cm long and weighed (on Earth, where the gravitational pull is 2? times Mars's) 10kg. Spirit and Opportunity, its twin successors, were larger, at 1.6 metres and 170kg. Curiosity, by comparison, is a monster. At 3 metres and 900kg it is the size of a small car. It also uses different technology. The other three rovers were powered by solar panels. Curiosity is powered by plutonium. (Not a full-scale reactor⁶, but a generator⁷ that turns the heat of radioactive decay into electrical energy.) This brings three advantages. First, it allows Curiosity to carry more power-hungry scientific instruments than previous rovers. Second, it permits the rover to work through the Martian winter. Third, it avoids the problem of dust accumulating on the solar panels, which gradually sapped the strength of its predecessors⁸.

　　1997年，NASA的火星漫游者"旅居者"到达火星，它长65厘米，重10千克（地球引力是火星的2.5倍）。其继任者，双胞胎"勇气和机遇号"比它更大（1.6米、170千克）。相比之下，"好奇号"就是个怪物。其3米长、900公斤重的尺寸就像一部小汽车。它也有不同的技术，之前漫游者由太阳能面板提供能量，"好奇号"由钚驱动（不完全是反应堆，而是一个将放射衰变产生的热能转换成电能的发电机）。这有三点好处：1、比起之前的漫游者，它能让"好奇号"带上更多的能耗大的科学仪器；2、它允许漫游者在火星冬季保持运转。3、它能避免让前几个漫游者的能量逐渐损耗的太阳能面板积土问题。

　　Curiosity's size makes getting it safely onto the Martian surface tricky⁹. Previous rovers have deployed¹⁰ parachutes to slow their descents, and have then crashed into the ground using airbags to cushion their impacts. Curiosity is too massive for that approach to work. Instead, NASA hopes to deposit it on Mars using a contraption it has dubbed¹¹ a skycrane.

　　"好奇号"的尺寸使之能在火星复杂表面安全着陆。以前，漫游者打开降落伞减慢下降速度，在撞向地面时用安全气囊缓冲。"好奇号"大到这样的方法不能起作用。相反地，NASA希望利用一种精巧的被称为"天空起重机"的装置使其在火星着陆。

　　As with the other rovers, Curiosity's mother ship will rely on heat shields and air-resistance, and then on a parachute, to slow its arrival. But at an altitude of 1.6km a specially¹² designed descent stage bearing the rover will drop away from this vehicle. The descent stage has eight rocket motors on its corners. These will slow its fall to a relatively¹³ sedate¹⁴ 0.75 metres a second. When it is about 20 metres above the surface, the rover will be lowered from it on wires and deposited gently onto the Martian landscape. The cables will then be cut with explosives, the descent stage will fly off and crash land elsewhere, and Curiosity will begin its mission.

　　像其它几个漫游者一样，"好奇号"的母船将依靠隔热、耐大气摩擦的防护层，然后通过降落伞减速。但在1600米高时，一个特别设计的背负着漫游者的下降台从母船脱落，下降台的四角有8个火箭发动机，这些发动机把速度降到相对缓慢的0.75米/秒。离地约20米时，它将绑在线缆上的漫游者放下去，轻轻地在火星着陆。之后这些线缆将通过爆破切断，下降台飞走并在其它地方坠毁，"好奇号"开始它的任务。

　　That, at least, is the theory. But the skycrane has never been used before, and there is plenty else that could go wrong. Indeed, Mars has something of a reputation for destroying spacecraft. Around half the missions sent there since the first Soviet¹⁵ attempts in 1960 have failed to arrive. A conversation on the subject in 1964, between a journalist and John Casani, a NASA scientist, spawned¹⁶ the idea of a Great Galactic Ghoul, a malevolent¹⁷ creature that prowls the space-lanes between Earth and Mars, dining on unfortunate spacecraft.

　　这至少还是理论。除"天空起重机"从未用过外，可能出岔子的地方还有很多。火星有着宇宙飞船毁灭者的名声，自1960年苏联第一次尝试以来，约一半的登陆任务已经失败。1964年，NASA科学家约翰·卡萨尼与一名记者就这个问题有过一次对话，并得出了"星系食尸鬼"的概念——一个险恶的、徘徊在地球与火星之间航线的、以不幸的宇宙飞船为食的家伙。

　　The ghoul's latest victim appears to have been Phobos-Grunt, an ambitious Russian mission that was intended to return to Earth with a rock sample from Phobos, the larger of Mars's moons. The Russian space agency's engineers lost contact with it soon after its launch on November 8th. Limited contact had been re-established as The Economist¹⁸ went to press, but it is not clear whether the mission can be salvaged¹⁹. NASA's engineers, rationalists though they be, will be keeping their fingers crossed on Saturday, and hoping that the ghoul's appetite has thus been sated, and that it will leave Curiosity alone.

　　最近一个亡于"食尸鬼"的似乎是俄罗斯的"福布斯—土壤"。一个雄心勃勃的打算把火星较大一颗卫星——火卫一的岩石标本带回地球的任务。11月8日，在发射不久，俄罗斯太空机构的工程师与它失去了联系。本刊截稿时，他们已经重新建立起有限的联系。尽管是理性主义者，NASA的工程师还是会在周六祈祷，希望"食尸鬼"的胃已经填饱了，而不去理睬"好奇号"。

1 prodded   

v.刺，戳( prod的过去式和过去分词 )；刺激；促使；（用手指或尖物）戳

参考例句：

• She prodded him in the ribs to wake him up. 她用手指杵他的肋部把他叫醒。
• He prodded at the plate of fish with his fork. 他拿叉子戳弄着那盘鱼。 来自《简明英汉词典》

2 assortment   

n.分类，各色俱备之物，聚集

参考例句：

• This shop has a good assortment of goods to choose from.该店各色货物俱全，任君选择。
• She was wearing an odd assortment of clothes.她穿着奇装异服。

3 ascend   

vi.渐渐上升，升高；vt.攀登，登上

参考例句：

• We watched the airplane ascend higher and higher.我们看着飞机逐渐升高。
• We ascend in the order of time and of development.我们按时间和发展顺序向上溯。

4 cape   

n.海角，岬；披肩，短披风

参考例句：

• I long for a trip to the Cape of Good Hope.我渴望到好望角去旅行。
• She was wearing a cape over her dress.她在外套上披着一件披肩。

5 sojourner   

n.旅居者，寄居者

参考例句：

• The sojourner has been in Wales for two weeks. 那个寄居者在威尔士已经逗留了两个星期。 来自互联网
• A sojourner or a hired servant shall not eat of it. 出12:45寄居的、和雇工人、都不可吃。 来自互联网

6 reactor   

n.反应器；反应堆

参考例句：

• The atomic reactor generates enormous amounts of thermal energy.原子反应堆发出大量的热能。
• Inside the reactor the large molecules are cracked into smaller molecules.在反应堆里，大分子裂变为小分子。

7 generator   

n.发电机，发生器

参考例句：

• All the while the giant generator poured out its power.巨大的发电机一刻不停地发出电力。
• This is an alternating current generator.这是一台交流发电机。

8 predecessors   

n.前任( predecessor的名词复数 )；前辈；（被取代的）原有事物；前身

参考例句：

• The new government set about dismantling their predecessors' legislation. 新政府正着手废除其前任所制定的法律。 来自《简明英汉词典》
• Will new plan be any more acceptable than its predecessors? 新计划比原先的计划更能令人满意吗？ 来自《简明英汉词典》

9 tricky   

adj.狡猾的，奸诈的；(工作等)棘手的，微妙的

参考例句：

• I'm in a rather tricky position.Can you help me out?我的处境很棘手，你能帮我吗？
• He avoided this tricky question and talked in generalities.他回避了这个非常微妙的问题，只做了个笼统的表述。

10 deployed   

（尤指军事行动）使展开( deploy的过去式和过去分词 )； 施展； 部署； 有效地利用

参考例句：

• Tanks have been deployed all along the front line. 沿整个前线已部署了坦克。
• The artillery was deployed to bear on the fort. 火炮是对着那个碉堡部署的。

11 dubbed   

v.给…起绰号( dub的过去式和过去分词 )；把…称为；配音；复制

参考例句：

• Mathematics was once dubbed the handmaiden of the sciences. 数学曾一度被视为各门科学的基础。
• Is the movie dubbed or does it have subtitles? 这部电影是配音的还是打字幕的？ 来自《简明英汉词典》

12 specially   

adv.特定地；特殊地；明确地

参考例句：

• They are specially packaged so that they stack easily.它们经过特别包装以便于堆放。
• The machine was designed specially for demolishing old buildings.这种机器是专为拆毁旧楼房而设计的。

13 relatively   

adv.比较...地，相对地

参考例句：

• The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
• The operation was relatively painless.手术相对来说不痛。

14 sedate   

adj.沉着的，镇静的，安静的

参考例句：

• After the accident,the doctor gave her some pills to sedate her.事故发生后，医生让她服了些药片使她镇静下来。
• We spent a sedate evening at home.我们在家里过了一个恬静的夜晚。

15 Soviet   

adj.苏联的，苏维埃的；n.苏维埃

参考例句：

• Zhukov was a marshal of the former Soviet Union.朱可夫是前苏联的一位元帅。
• Germany began to attack the Soviet Union in 1941.德国在1941年开始进攻苏联。

16 spawned   

（鱼、蛙等）大量产（卵）( spawn的过去式和过去分词 )； 大量生产

参考例句：

• The band's album spawned a string of hit singles. 这支乐队的专辑繁衍出一连串走红的单曲唱片。
• The computer industry has spawned a lot of new companies. 由于电脑工业的发展，许多新公司纷纷成立。

17 malevolent   

adj.有恶意的，恶毒的

参考例句：

• Why are they so malevolent to me?他们为什么对我如此恶毒？
• We must thwart his malevolent schemes.我们决不能让他的恶毒阴谋得逞。

18 economist   

n.经济学家，经济专家，节俭的人

参考例句：

• He cast a professional economist's eyes on the problem.他以经济学行家的眼光审视这个问题。
• He's an economist who thinks he knows all the answers.他是个经济学家，自以为什么都懂。

19 salvaged   

（从火灾、海难等中）抢救（某物）( salvage的过去式和过去分词 )； 回收利用（某物）

参考例句：

• The investigators studied flight recorders salvaged from the wreckage. 调查者研究了从飞机残骸中找到的黑匣子。
• The team's first task was to decide what equipment could be salvaged. 该队的首要任务是决定可以抢救哪些设备。