Objectives & Sequence: This lesson is intended to be used as a preview of Grammar - Reported Speech #1.
Part One: Warm Up
Discuss the following questions with a partner or group:
- Have you ever studied astronomy? If not, would you be interested in learning about it in the future?
- What is a light year? How long is it?
- What is the difference between a star and a planet?
- How can astronomers see galaxies far away?
- How many zeros are in a million? What about billion? Trillion?
Part Two: Listening
Exercise
Open Exercise One to begin the activity. Follow the instructions in the document. Then, go on to Exercise Two.
Transcript
John: Hey.
Person 1: Hey, how's it going?
John: Not bad. How's your astronomy class going?
Person 1: Oh man, I love it. It's really interesting. Dr. Davis really knows what he's talking about.
John: Dr. Davis? Is that your professor?
Person 1: Yeah, sorry. I'm glad you're enjoying it. What kinds of topics does he discuss?
John: Well, we've talked about so much already, like planets, galaxies, solar systems, things like comets and shooting stars and other stuff. I had no idea the universe was as big as it is.
Person 1: What do you mean? How big is it?
John: Well, that's not a very easy question to answer. Actually, Dr. Davis told us that astronomers didn't know the full size of the universe. He said that with our best telescopes, astronomers could see about 91 billion light years away.
Person 1: Okay, but what is a light year?
John: Yeah, actually, I didn't know what that was either until this class. Dr. Davis explained that a light year was the distance that light traveled in one year and that it was about 9 trillion kilometers long.
Person 1: Trillion? So what is that? 11, no, 12 zeros, right?
John: Yeah, exactly.
Person 1: Whoa, you're right. I guess that is pretty big. And it's even more amazing to think about how many galaxies, solar systems, and planets there are.
John: Really? How many are there?
Person 1: Well, again, we only know as much as we can see, but so far, scientists are able to see about 500 different solar systems clearly. And these solar systems are only in our part of the galaxy. Dr. Davis said that if there were this many solar systems in the rest of the galaxy, there could be up to 100 billion planets in just the Milky Way, which is the name of our galaxy.
John: 100 billion planets in only our galaxy alone? How many galaxies are there?
Person 1: Dr. Davis said the universe contained at least 100 billion galaxies.
John: 100 billion galaxies, really? So you said that in our galaxy, there were up to 100 billion planets, right? So if every other galaxy out there had 100 billion planets, how many planets does that mean there are in the universe?
Person 1: I don't know the answer, but it would be a really big number.
John: Yeah, you have to be pretty good at math to take this course, don't you?
Person 1: Astronomy is interesting, isn't it?
John: Sure is.