英语听力文摘 English Digest 726 从小行星手里拯救世界

Saving the World from Asteroids²

Okay, so there’s an asteroid¹ heading toward the Earth. What do we do? Does our future really rest in the hands of Hollywood, Bruce Willis and a ragtag team of miners like in the movie Armageddon?

Early Warning

Sure, we could wait until danger is imminent³ and then hope that a well placed nuclear explosion would shatter or deflect⁴ the monster asteroid threatening humanity, but is this our only option? The answer is that it depends on how big the asteroid is, how far away it is, and How much time we have before impact?

Because there’s lots of space debris⁵ out there, odds⁶ are that the threatening object won’t be one of the giant Earth-destroying asteroids that NASA is already tracking, but a smaller meteoroid capable of causing regional devastation⁷.

With enough warning, though, we could crash a robotic spacecraft into the object and change its trajectory⁸ so that it’ll sail by Earth. We know we have the technology for this, because NASA has already successfully rammed⁹ a spacecraft into a comet to study the comet’s composition.

Deflection

There are also rare instances when space objects pass close by several years before returning on a collision course with Earth. Here even a tiny change in trajectory during the first pass would result in big payoff later. In these cases, we could use a spacecraft’s mass and gravitational field to nudge the space object off course without shattering it and creating potentially dangerous fragments.

Obviously, early warning is key, which is why NASA has issued a grand challenge to scientists in various disciplines, institutions and agencies to work together to uncover ways of detecting, characterizing and interacting with asteroids. Because when it comes to the future of the Earth, Bruce Willis can only do so much.

1 asteroid   

n.小行星；海盘车(动物)

参考例句：

• Astronomers have yet to witness an asteroid impact with another planet.天文学家还没有目击过小行星撞击其它行星。
• It's very unlikely that an asteroid will crash into Earth but the danger exists.小行星撞地球的可能性很小，但这样的危险还是存在的。

2 asteroids   

n.小行星( asteroid的名词复数 )；海盘车，海星

参考例句：

• Asteroids,also known as "minor planets",are numerous in the outer space. 小行星，亦称为“小型行星”，在外太空中不计其数。
• Most stars probably have their quota of planets, meteorids, comets, and asteroids. 多数恒星也许还拥有若干行星、流星、彗星和小行星。

3 imminent   

adj.即将发生的，临近的，逼近的

参考例句：

• The black clounds show that a storm is imminent.乌云预示暴风雨即将来临。
• The country is in imminent danger.国难当头。

4 deflect   

v.(使)偏斜，(使)偏离，(使)转向

参考例句：

• Never let a little problem deflect you.决不要因一点小问题就半途而废。
• They decided to deflect from the original plan.他们决定改变原计划。

5 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。

6 odds   

n.让步，机率，可能性，比率；胜败优劣之别

参考例句：

• The odds are 5 to 1 that she will win.她获胜的机会是五比一。
• Do you know the odds of winning the lottery once?你知道赢得一次彩票的几率多大吗？

7 devastation   

n.毁坏；荒废；极度震惊或悲伤

参考例句：

• The bomb caused widespread devastation. 炸弹造成大面积破坏。
• There was devastation on every side. 到处都是破坏的创伤。 来自《简明英汉词典》

8 trajectory   

n.弹道，轨道

参考例句：

• It is not difficult to sketch the subsequent trajectory.很容易描绘出它们最终的轨迹。
• The path followed by a projectile is called its trajectory.抛物体所循的路径称为它的轨道。

9 rammed   

v.夯实（土等）( ram的过去式和过去分词 )；猛撞；猛压；反复灌输

参考例句：

• Two passengers were injured when their taxi was rammed from behind by a bus. 公共汽车从后面撞来，出租车上的两位乘客受了伤。
• I rammed down the earth around the newly-planted tree. 我将新栽的树周围的土捣硬。 来自《简明英汉词典》