实用大学英语综合教程3课件王淙 马青丁晶 ISBN 9787566310965 PPTUnit 6.ppt

Unit 6 Homecoming 张艳华 制作 Answers to Listening: First conversion： W: Doctor Cole, thank you for agreeing, to this interview for the Daily Campus News. Can you tell us about what you and your colleagues discussed at the annual astronomy society meeting last month? M: Yes. For the first time ever, the scientific community has established the existence of planets outside our own solar system. Of course, we knew that certain distant stars existed, but only recently did we learn that several of them are orbited by their own planets. W: Why did it take so long to locate those planets? M: Well, you have to understand that they are a billion times dimmer than their parent stars. It would be like trying to see the light of a candle next to a huge explosion. We dont currently have a telescope that can be used to see them. W: But if the astronomers didn’t see the planets through a telescope, how did they find them? M: By a very indirect method. Umm, the astronomers measured subtle distortions in the frequency of the light from the parent stars and observed that some of the stars seem to rock back and forth, they determined that this is caused by the gravitation pull from orbiting planets. W: There is a powerful new telescope being built in Arizona. Will that help them see these planets? M: They should be able to see them at least in the form of small spots of light. And then the scientists would be able to break down and analyze this light. By doing so, they hope to learn about the chemical composition of these planets. Oxygen and ozone molecules, for example, would be telltale signs of life on these planets. W: Im looking forward to hearing more when the telescope is in operation and Im sure our readers would be interested too. Questions 1 to 3 are based on the passage you have just heard. 1. What is the purpose of the conversation? 2. What is the conversation mainly about? 3. How did scientists establish the existence of the planets? 1. C 2. D 3. B