外研版选修四册第六单元听力练习

Unit 6 Space and beyond

Host: Hello and welcome to Hot Topic. Today I'm talking to physicist Peter Xu about space debris. Peter, what is space debris?

Peter: It's pieces of rubbish or useless material that are left over when something breaks. It could be old satellites, parts of satellites or paint chips. They orbit the Earth. As far as I'm concerned, it's the biggest threat to the space industry.

Host: Why do you say that?

Peter: In my opinion, space debris makes space travel more dangerous. There are currently about 500,000 pieces of space debris larger than one centimetre.

Host: Surely the small pieces aren't dangerous though?

Peter: Conceivably, they are, because they're travelling at 28,000 kilometres per hour. A five-centimetre piece of space debris has as much energy as a speeding bus.

Host: Let's hope there are no collisions. But don't all these pieces of rubbish fall back to Earth and burn up in the atmosphere?

Peter: Some of them do so quickly, but others are out there a long time. New space debris is also being created all the time.

Host: To me, this seems like a huge problem. Are there plans to clear it up?

Peter: Scientists are working on a number of solutions. I'm hopeful that one of them proves successful. In 2016, China launched Aolong-1. It's an experimental satellite with a robotic arm that pushes debris into the atmosphere. In Europe, scientists are building a satellite with a huge net that can capture debris. American scientists want to shoot gas at space debris to slow it down, so it falls out of orbit.

Host: It would be wonderful if we cleared this mess up. Are you optimistic?

Peter: Yes, I am. With luck, we can make space safe and useful for future generations.

Host: Peter Xu, thank you very much.