英语听力文摘 English Digest 517、地球同步卫星（一）

 　　A Stationary¹ Satellite, part 1

 

　　Some of the best devices in science have been anticipated by science fiction writers years before they existed. Occasionally a writer comes up with an idea that can be put into practice within their lifetime!

 

　　Such is the case with the geostationary satellite, first imagined by Arthur C. Clarke. Clarke, famous for writing “2001: A Space Odyssey,” also wrote a scientific article titled “Extra-Terrestrial Relays” in 1945. In it, he proposed a satellite that would remain motionless in the air, rather than passing by overhead. Such a “fixed²” satellite would be useful for relaying television and radio signals, helping³ ships navigate⁴, and a host of other things.

 

　　But how to do it? After all, heavy machinery⁵ can’t just float. Most satellites handle this problem by being blasted into orbit around the planet. But in order to be in orbit, you have to be constantly moving. Can you think of a way around this?

 

　　How about putting a satellite into orbit both in the same direction as the planet rotates–and at the same speed! The result is a satellite that is, in fact, orbiting the planet. But the ground underneath⁶ it turns at the same rate as the satellite orbits, so the satellite is always above the same spot of ground. From our perspective on the earth, a geostationary satellite seems fixed in one spot.

1 stationary   

adj.固定的，静止不动的

参考例句：

• A stationary object is easy to be aimed at.一个静止不动的物体是容易瞄准的。
• Wait until the bus is stationary before you get off.你要等公共汽车停稳了再下车。

2 fixed   

adj.固定的，不变的，准备好的；(计算机)固定的

参考例句：

• Have you two fixed on a date for the wedding yet?你们俩选定婚期了吗？
• Once the aim is fixed,we should not change it arbitrarily.目标一旦确定，我们就不应该随意改变。

3 helping   

n.食物的一份&adj.帮助人的，辅助的

参考例句：

• The poor children regularly pony up for a second helping of my hamburger. 那些可怜的孩子们总是要求我把我的汉堡包再给他们一份。
• By doing this, they may at times be helping to restore competition. 这样一来, 他在某些时候,有助于竞争的加强。

4 navigate   

v.航行，飞行；导航，领航

参考例句：

• He was the first man to navigate the Atlantic by air.他是第一个飞越大西洋的人。
• Such boats can navigate on the Nile.这种船可以在尼罗河上航行。

5 machinery   

n.(总称)机械，机器；机构

参考例句：

• Has the machinery been put up ready for the broadcast?广播器材安装完毕了吗？
• Machinery ought to be well maintained all the time.机器应该随时注意维护。

6 underneath   

adj.在...下面，在...底下；adv.在下面

参考例句：

• Working underneath the car is always a messy job.在汽车底下工作是件脏活。
• She wore a coat with a dress underneath.她穿着一件大衣，里面套着一条连衣裙。