There is an asteroid on a collision course with the Earth.

有个小行星正处于可能与地球发生碰撞的航向上。

Scientists were debating whether an asteroid was about to hit the Earth.

科学家们在争论一颗小行星是否要撞上地球。

The largest asteroid is Ceres, which is about a quarter the size of the moon.

最大的小行星是谷神星，其体积大约是月球的四分之一。

In this case, the orbit of the rotating asteroid will very slowly spiral toward the sun.

在这种情况下，旋转小行星的轨道将非常缓慢地向太阳旋转。

An asteroid could have annihilated the USA—and I wouldn't have heard the news for hours.

一颗小行星可能已经把美国毁灭了——而我可能几个小时内都没有听说这个消息。

Astronomers have detected an asteroid not far from Earth, moving in the same orbit around the Sun.

天文学家在距离地球不远处发现一颗小行星，它与地球在同一轨道上围绕太阳运行。

This iridium anomaly offers strong support for the Alvarez hypothesis even though no asteroid itself has ever been discovered.

这一铱异常为阿尔瓦雷斯假说提供了强有力的支持，尽管小行星本身从未被发现。

Some scientists hypothesize that the extinction of the dinosaurs resulted from the effects of an asteroid collision with Earth.

一些科学家假定，小行星撞击地球导致了恐龙的灭绝。

An asteroid of this size would be expected to leave an immense crater, even if the asteroid itself was disintegrated by the impact.

这样大小的小行星即使受到冲击碎裂之后也会留下一个巨大的陨石坑。

Moving on through the asteroid belt we enter the realms of the gas giant planets: Jupiter, Saturn, Uranus, and Neptune, all of which dwarf the Earth.

穿过小行星带继续前进，我们进入了气体巨行星区域：木星、土星、天王星、海王星，所有这些都使地球看起来像个侏儒。

Debris thrown into the atmosphere by an asteroid collision would presumably contain large amounts of iridium, and atmospheric currents would carry this material all over the globe.

小行星碰撞后的碎片可能会含有大量的铱，而大气洋流会把这些物质带到全球各地。

Paradoxically, while the temperatures required for liquid water exist only in the inner solar system, the key building blocks of life, including water itself, occur primarily beyond the asteroid belt.

矛盾的是，虽然液态水所需的温度只存在于太阳系内部，但生命的关键组成部分，包括水本身，却主要存在于小行星带之外。

Now utopia has grown unfashionable, as we have gained a deeper appreciation of the range of threats facing us, from asteroid strike to epidemic flu and to climate change.

现如今，这种乌托邦空想已经过时了，我们对所面临的威胁有了更深刻的认识，从彗星撞击到流行感冒，再到气候变化。

She is orbiting the sun as the asteroid 216 Kleopatra.

编号为216 Kleopatra 的小行星正绕着太阳运行。

Will an asteroid hit the Earth?

会不会发生小行星撞击地球的事件呢？

"Asteroid strike?" said Aziraphale.

“小行星撞击？”亚茨拉菲尔说。

Some of them could even become the first to visit an asteroid.

他们中的一些甚至可能第一个访问小行星。

It will probably be easier to do this on the moon than on an asteroid.

显然，在月球上完成这个任务比在小行星上完成要容易。

If the world wants to know about an asteroid, we have the catalog.

如果世界上有人要了解某颗小行星，我们这里就有它的目录。

The bad news is that forecasting asteroid impacts remains a tricky business.

坏消息是预测小行星撞击不是件容易事。

Then one day a big, bad asteroid came along and wiped out all the dinosaurs.

突然有一天,一个巨大且极具摧毁性的小行星的降临灭绝了所有的恐龙;

The goal of the program is to send astronauts to explore an asteroid by 2025.

该项目的目标是在2025年把宇航员送入太空去探索小行星。

Potential destinations include an asteroid, the moon and eventually Mars.

现在以确定的潜在目的地有小行星，月球，当然最终自然是火星。

The asteroid was first spotted during a routine survey performed by a satellite.

这颗小行星是在一次例行检查中被一颗卫星发现的。

The agency's plans to send humans to Mars or an asteroid are in deep freeze.

该机构将人类送上火星或小行星的计划也同样束之高阁。

Perhaps we'll fail to mitigate the threat posed by asteroid and comet collisions.

我们也许会没能成功地减轻小行星和彗星碰撞所带来的威胁。

But until now, no such asteroid-asteroid collision has been caught "in the act".

但是，直到今天，我们都没有“当场”捕捉到这种小行星对小行星的碰撞。

The dinosaurs were done for, as everybody knows, by a collision with an asteroid.

正如大家所知，恐龙的终结是由于地球与一个小行星发生碰撞。