节目资讯
刊物:空中英语教室
日期:2014-02-18
难易度:Medium
关键字:orbit, potential, realm, disbelief, tether, breakthrough, carbon nanotube
Hey, everyone.
Welcome back.
Well, have you ever played with a (Chinese) before, a Chinese yo-yo?
You know, today we're learning more about the space elevator.
And it kind of reminds me of when I learned a special trick on the (Chinese)
called (Chinese).
Let's see if I can do it here.
All right.
You know, if only the space elevator were that simple.
But we're going to need something a lot stronger than this string.
You see, we have all of the technology necessary to build a space elevator
except the carbon nanotube ribbon that will take the climber up.
Is the space elevator a possibility for the future?
Well, let's continue reading and find out.
The Space Elevator.
But they are extremely short - the longest measured in centimeters.
Scientists are still working on combining these tiny tubes into longer strands.
So, producing a ribbon that could reach the International Space Station is still
in the realm of science fiction.
But the wait may not be long.
Japanese company Obayashi promises to build a space elevator by 2050, causing
some to laugh in disbelief.
But as science-fiction writer Arthur C. Clarke said, the space elevator would be
built "about 10 years after everyone stops laughing.".
(Music).
All right.
(Chinese).
And now let's go to our teachers.
Thanks, Michelle.
We're learning about these carbon nanotubes, which can be up to 100 times
stronger than steel.
The only problem is they are extremely short.
Right, the longest measured in mere centimeters, only a couple of centimeters
long.
Well, that's OK.
Scientists are still working on combining these tiny tubes into longer strands.
If you work on something, that means you are trying to improve it or make it
more complete.
Yes. And we often use this phrase.
For example, every night in high school I had to work on my homework.
Well, we are always working on our show here at Studio Classroom to make it
better and better.
And scientists are working on space technology so that one day, we will be able
to take trips to space and back via space elevator.
But for now, we read:
Producing a ribbon that could reach the International Space Station is still in
the realm of science fiction.
And of course science fiction is made-up stories that rely on scientific ideas.
Fiction is not true.
And there is a book called The Fountains of Paradise by Arthur C. Clarke that
includes this idea of a space elevator.
So our author says that this space elevator is still in the realm, or world, of
science fiction.
Of course, some things have moved out of the realm of science fiction like 3-D
printers and self-driving cars.
They used to be in the realm of science fiction, and now we can use them.
But a ribbon that can reach the International Space Station is still considered
part of science fiction.
However, did you know that the ribbon is supposed to reach much farther than the
International Space Station?
No. How far is it supposed to go?
Well, one idea is that it reaches 100,000 kilometers from the Earth.
The International Space Station, at its furthest, is just 300... or 435
kilometers high.
Wow! That's more than 200 times farther than the International Space Station.
Right. Of course there are many things to take into consideration.
You know one thing that I would worry about is space debris.
And that is all the pieces of large and small things that are orbiting the
Earth.
Yes. That was the main problem in the movie Gravity that came out a few months
ago.
Even really tiny space debris travels at 36,000 kilometers per hour.
That's more than 10 times faster than a gun's bullet.
And that's why the space elevator, while it sounds really cool, also sounds a
little bit dangerous to me.
There are over millions... there are many millions of pieces of space debris
flying around up there at those speeds.
You're going to need a lot more than a seat belt up there.
Well, I agree with that.
And right now it's time for us to learn some more with Steve and Ken in the
Information Cloud.
And then we'll watch a review skit, and join Linda for the Editor's Summary.
Inventors are always getting laughed at by others.
People just love saying: It can't be done!
That's right.
We have a word for these kinds of people: detractors.
There are plenty of them right now, in fact, laughing and saying the space
elevator is an impossibility.
Well, maybe someday soon we'll see space elevator engineers like those at the
Japanese Obayashi Company get the last laugh.
Right.
Getting or having the last laugh is an idiom we use when people who are made fun
of for some reason finally find success.
Right. They may have been regarded as failures, fools or losers.
But then, over time and for various reasons, they find success, and so triumph
over their detractors.
So the people who were being laughed at, in the end, get to do some laughing of
their own.
That's right.
Another example, let's say there was a girl in your class who was unusually tall
and gangly.
And because of that, she often got teased by others.
Years later, because of her height and her hard work, you discover she's become
a successful fashion model.
The girl who got laughed at got the last laugh.
(Chinese).
What floor, please?
Elevators are so convenient.
Yes. What floor, please?
You know, someday an elevator will take us into space.
An elevator into space?
That's funny.
I'm serious.
We'll stretch a cable from Earth to an object in space.
Stretch a cable to space?
I'm serious.
Cars will ascend the cable much like an elevator.
That cable will have to be long and strong.
Exactly, stronger than steel yet very lightweight.
Impossible.
And long enough to reach a space station.
Impossible.
But scientists have made a breakthrough.
What breakthrough?
Carbon nanotubes.
They're 100 times stronger than steel.
That's strong.
But what about long?
It's already a few centimeters.
It sounds like making a long cable is going to take a long time.
True. A space elevator is still in the realm of science fiction.
Yeah.
But it's coming!
When?
About 10 years after you stop laughing.
Then it will be a long time because I can't stop laughing.
Oh... what floor? I mean, what planet? Saturn or Mars?
You'll see!
(Music).
Today it is possible to build several parts of the space elevator.
However, the ribbon or the cable that would act like the tether holding to the
Earth and the object in space is a potential problem.
It must be stronger than steel and very lightweight.
In 1991 there was a potential breakthrough with the discovery of carbon
nanotubes.
They are 100 times stronger than steel.
But the big problem is that they are extremely short.
So scientists have to find a way to combine them.
It seems like such a long way off.
But Obayashi, a Japanese company says that it will build the space elevator by
2050.
And while some may be laughing at the idea, Arthur Clarke thinks it will exist
about 10 years after people stop laughing.
Thank you, Linda.
And thank you for joining us for our lesson about the future of space travel.
You know there is still so much more to discover out there.
Maybe one day ordinary people like you and me will be able to enjoy space travel
at the same price as a plane ticket.
That would be amazing.
Well, tomorrow we're talking about something completely different - shopping.
So join us then right here at Studio Classroom.
We'll see you then.