Space elevators — yes, literal elevators that will carry us into orbit-may not be as far from reality as we think, says Stephen Cohen, a space engineer and physics professor. According to his ideas, such a wild concept could be realistic relatively soon.
So, what exactly is a space elevator? Well, humans are headed to Mars by 2040, if all goes well, and one of the largest issues is the transport. Getting people up to space is a difficult and expensive task. A much better way, some believe, could be to put a really, really long cable (电缆) from the Earth’s surface all the way to orbit, and pass a pod (分离舱) up and down the cable. It would save on fuel, reduce overall expenses, and be far less dangerous than rockets.
However, as you can imagine, though, space elevators do not come without significant questions. For example, how would the rope stay tight? How could we ensure that nothing comes along and destroys the cable, like terrible weather or space junk? How would you even build such a thing?
Stephen Cohen, a long-time space elevator enthusiast, believes he has all the answers: Basically, a satellite orbiting Earth drops a cable(a very, very long one) while using fuel to get away from the Earth further into space. In this way the cable remains tight as it is fastened to the ground.
Unfortunately, modern tech can’t solve this because the cable needs a specific strength of around 50 times that of steel. But according to Cohen, we’re likely around 10 years away from the material being made and we shall be walking on Mars even before 2040.
Most scientists remain unconvinced — space elevators have been spoken about for years and yet a lot of questions are to be answered. But, who knows, maybe the days of fastening ourselves to rockets could soon be over; we can only imagine the astronauts would welcome the day.
8. What advantage does the space elevator have over the traditional transport?
A.Smaller noise. | B.Higher speed. | C.Less cost. | D.Better protection |
9. What is paragraph 3 mainly about?
A.The operating steps of the space elevator. | B.The obvious benefits of the space elevator. |
C.The potential impacts of the space elevator. | D.The possible challenges of the space elevator. |
10. What makes it impossible to build a space elevator now?
A.The high risks are difficult to predict accurately |
B.The dangerous tasks are hard to fulfil successfully. |
C.The required material is not technologically available. |
D.The fuel-burning satellite will lead to serious pollution. |
11. What is most scientists’ attitude towards the space elevator?
A.Doubtful. | B.Unconcerned. | C.Favorable. | D.Opposed. |