英语听力文摘 English Digest 361、小小灶神星

Vesta 灶神星

 

You can see the planet Jupiter on a clear night, but Jupiter is humongous. Mars and Mercury are smaller than that, and you can see them, too. Wait a minute, our moon is even smaller, and you can see that. Could anything smaller than the moon be visible without a telescope?

 

Actually, yes. Though it takes a lot of patience and excellent sky conditions, it is possible to see a tiny object called Vesta. Although it had a molten interior and volcanoes, Vesta isn’t a planet or a moon: it’s an asteroid. Asteroids are straychunks of rocky or metallic¹ materials that orbit the sun but were never drawn² into any of the planets.

 

Vesta is quite far away. Like many asteroids, it has an orbit out between the orbits of Mars and Jupiter. Astronomers³ first spotted⁴ it when looking for a new planet they thought should exist between these two.

 

As I said, Vesta is quite small–about three hundred and twenty-five miles across. So if it’s small and far away, how come we can see it from here? Vesta’s surface has a coating of pyroxine and olivine, two minerals that are actually also spewed up by volcanoes here on earth. They give it a whitish exterior⁵ that reflects well, making it just possible to see Vesta with your eyes, even when the only two larger asteroids, Ceres and Pallas, are completely invisible.

 

 

在晴朗的夜空下我们能够看到木星，那是因为木星够大；尽管火星和水星比木星要小，但我们依然能看到。等等，月球更要小一些，我们还是能看到。那么，在不使用望远镜的情况下，我们还能看到比月亮更小的天体吗？

 

事实上，答案是肯定的。只要我们足够有耐心，天公也作美，我们还有机会看到一个小天体——它就是被命名为灶神星的小天体。尽管它以溶化的金属为核心且地表遍布火山，灶神星却既不是行星也不是月球：它仅仅是一颗小行星。小行星是由岩石或是金属块构成的小天体，他们绕太阳运动但绝不会卷入其他行星的运行轨道中。

 

灶神星距地球的距离很远。像其它许多小行星一样，它在火星与木星之间有自己的运行轨道。天文学家们首次发现它时是在寻找介于这两大行星间的另一个行星。

 

正如我所说，灶神星是很小的——它的直径也就只有325英里而已。那问题就是，它又小，距离我们又远，我们怎么能从地球上靠肉眼就看到它呢？在灶神星的表面覆盖了厚厚的一层玄武岩和橄榄石，这两种矿物质都是由此处的火上喷发而出的。这两种矿物质使得灶神星的表面呈白色，且发光的效果相当好。如此一来，我们便仅凭肉眼就可以看到灶神星了。甚至在比它还大的另外两个小行星——谷神星和智神星都无法看到的情况下，我们还是能看到它。

 

 

Note: spew up  喷出

 

1 metallic   

adj.金属的；金属制的；含金属的；产金属的；像金属的

参考例句：

• A sharp metallic note coming from the outside frightened me.外面传来尖锐铿锵的声音吓了我一跳。
• He picked up a metallic ring last night.昨夜他捡了一个金属戒指。

2 drawn   

v.拖，拉，拔出；adj.憔悴的，紧张的

参考例句：

• All the characters in the story are drawn from life.故事中的所有人物都取材于生活。
• Her gaze was drawn irresistibly to the scene outside.她的目光禁不住被外面的风景所吸引。

3 astronomers   

n.天文学者，天文学家( astronomer的名词复数 )

参考例句：

• Astronomers can accurately foretell the date,time,and length of future eclipses. 天文学家能精确地预告未来日食月食的日期、时刻和时长。 来自《简明英汉词典》
• Astronomers used to ask why only Saturn has rings. 天文学家们过去一直感到奇怪，为什么只有土星有光环。 来自《简明英汉词典》

4 spotted   

adj.有斑点的，斑纹的，弄污了的

参考例句：

• The milkman selected the spotted cows,from among a herd of two hundred.牛奶商从一群200头牛中选出有斑点的牛。
• Sam's shop stocks short spotted socks.山姆的商店屯积了有斑点的短袜。

5 exterior   

adj.外部的，外在的；表面的

参考例句：

• The seed has a hard exterior covering.这种子外壳很硬。
• We are painting the exterior wall of the house.我们正在给房子的外墙涂漆。