英语听力：自然百科 穿越银河系的旅行 Through Milky Way—20

 They were once thought to mark the outer limits, but today astronomers¹ believe the Milky² Way galaxy³ is much bigger than what we can see. To understand why, we will travel to the stars of the outer galactic disc.  

 

 

 

Far from our usual place in space, we approach the edges of the galaxy where we may be able to discover what holds all the stars together to make our Milky Way. 

 

 

 

Here our night sky looks a little different, the Milky Way is smaller and the sky is darker, but even though with tens of thousands of light years further away from the center of our galaxy, we’re still bound to it by the force of gravity. 

 

 

 

Gravity is the force that makes any two objects on a move towards each other. 

 

 

 

On earth, cities are built from iron girders in concrete beams. This largely invisible scaffold holds these buildings up against the pull of the gravity. Without this scaffold in, the/ skyscrapers⁴ would crumble⁵, and the bridges would collapse⁶. 

 

 

 

But gravity not only governs us on earth, it governs throughout the universe. Its laws are straightforward⁷: anything that has mass has a gravitational pull; the greater the mass, the stronger the pull. 

 

 

 

With 200 billion stars, the Milky Way has a huge mass and tremendous gravitational attraction. So like buildings, our galaxy also needs propping⁸ up against the force of gravity.

1 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》

2 milky   

adj.牛奶的，多奶的；乳白色的

参考例句：

• Alexander always has milky coffee at lunchtime.亚历山大总是在午餐时喝掺奶的咖啡。
• I like a hot milky drink at bedtime.我喜欢睡前喝杯热奶饮料。

3 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。

4 skyscrapers   

n.摩天大楼

参考例句：

• A lot of skyscrapers in Manhattan are rising up to the skies. 曼哈顿有许多摩天大楼耸入云霄。
• On all sides, skyscrapers rose like jagged teeth. 四周耸起的摩天大楼参差不齐。

5 crumble   

vi.碎裂，崩溃；vt.弄碎，摧毁

参考例句：

• Opposition more or less crumbled away.反对势力差不多都瓦解了。
• Even if the seas go dry and rocks crumble,my will will remain firm.纵然海枯石烂，意志永不动摇。

6 collapse   

vi.累倒；昏倒；倒塌；塌陷

参考例句：

• The country's economy is on the verge of collapse.国家的经济已到了崩溃的边缘。
• The engineer made a complete diagnosis of the bridge's collapse.工程师对桥的倒塌做了一次彻底的调查分析。

7 straightforward   

adj.正直的，坦率的；易懂的，简单的

参考例句：

• A straightforward talk is better than a flowery speech.巧言不如直说。
• I must insist on your giving me a straightforward answer.我一定要你给我一个直截了当的回答。

8 propping   

支撑

参考例句：

• You can usually find Jack propping up the bar at his local. 你常常可以看见杰克频繁出没于他居住的那家酒店。
• The government was accused of propping up declining industries. 政府被指责支持日益衰败的产业。