【英语时差8,16】星际中的尘埃

When we think of outer space, we probably imagine--well--space: Vast empty regions with no air, no matter, no anything at all. Actually, where our Earth orbits, outer space is far from empty. It's downright dusty.  Beyond our atmosphere flies a lot of debris¹. Some fragments, known as asteroids², can be larger than mountains, but most are tiny specks³, pieces of rock, metal, or ice smaller than grains of sand. This space-dust isn't as thick as, say, the dust under your sofa. But still, there's enough debris out there so that some twenty tons of it flies into our atmosphere each day, often leaving fiery⁴ streaks⁵ that we call meteors.

Like a police officer uses a radar⁶ gun, scientists can use radar to find the speed of these meteors. Many clock in at around a hundred thousand miles an hour. This might seem fast, but it's actually well within the speed limit of dust specks orbiting our sun. What's surprising is that about one percent of these meteors hit us faster than two hundred twenty five thousand miles an hour. This is far too fast for them to be orbiting our sun. It's so fast that these meteors must have zipped in from outside our solar system.

Where do they come from? Some are probably expelled from nearby star systems, pushed by the radiation of these alien suns. Also, as our sun orbits the galactic center it may sweep through areas of interstellar dustiness.

The biggest shock are the rare meteors clocked at almost seven hundred thousand miles an hour. These are flying so fast, they must come from outside our galaxy⁷ itself!  

1 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。

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 specks   

n.眼镜；斑点，微粒，污点( speck的名词复数 )

参考例句：

• Minutes later Brown spotted two specks in the ocean. 几分钟后布朗发现海洋中有两个小点。 来自英汉非文学 - 百科语料821
• Do you ever seem to see specks in front of your eyes? 你眼睛前面曾似乎看见过小点吗？ 来自辞典例句

4 fiery   

adj.燃烧着的，火红的；暴躁的；激烈的

参考例句：

• She has fiery red hair.她有一头火红的头发。
• His fiery speech agitated the crowd.他热情洋溢的讲话激动了群众。

5 streaks   

n.（与周围有所不同的）条纹( streak的名词复数 )；（通常指不好的）特征（倾向）；（不断经历成功或失败的）一段时期v.快速移动( streak的第三人称单数 )；使布满条纹

参考例句：

• streaks of grey in her hair 她头上的绺绺白发
• Bacon has streaks of fat and streaks of lean. 咸肉中有几层肥的和几层瘦的。 来自《现代英汉综合大词典》

6 radar   

n.雷达，无线电探测器

参考例句：

• They are following the flight of an aircraft by radar.他们正在用雷达追踪一架飞机的飞行。
• Enemy ships were detected on the radar.敌舰的影像已显现在雷达上。

7 galaxy   

n.星系；银河系；一群(杰出或著名的人物)

参考例句：

• The earth is one of the planets in the Galaxy.地球是银河系中的星球之一。
• The company has a galaxy of talent.该公司拥有一批优秀的人才。