نطق سوم

Lecture 3:

Listen to part of a lecture in an astronomy class.

So your reading assignment focused on the technology telescopes and how they’ve changed astronomy. and there was a section on the hooker telescope. so why was the hooker telescope so important? let’s talk about that before we move on to some of the newer technologies. now, back in the 1920s, the hooker telescope was the most powerful telescope in the world. and through it we could see see for the first time that the universe extends far, far beyond the milky way Galaxy. we could see that there are multiple galaxies beyond it, and all these galaxies are moving away from one another.

So multiple galaxies moving away from each other LED to the theory, the Big Bang theory. Exactly. And that theory that 15 billion years ago when explosion started the expansion of the universe. well, at the time that was a pretty revolutionary idea. and the hooker telescope was responsible for that. Yes, because it allowed us to see that far. And being able to see that far LED to, well, it LED to the Big Bang theory. but let’s move on the reading assignment. Discussed another tool for scanning the universe, the interferometer. claudia. What can you tell me about inter for amateurs? okay. An interferometer is a machine made of two or more conventional telescopes. I think the example they gave in the book was made from six, and they’re spread out. They’re not right next to each other.

And then the light, the star light that those telescopes gather travels through pipes to some computers. and then the computers put all the light together to make one image. ok, good. although maybe that explanation is a bit simplistic. there may be a thousand or so meters of pipe carrying the star light from the telescopes to the computers, and then getting all those components to work together to synchronize.

So the light from all the different telescopes reaches the computers at exactly the same time. that’s the Challenge of working with inter for amateurs. what else can you tell me? What’s the advantage here? Paul? all right. I think the idea isn’t that it sees farther, but that the image you see is a lot sharper. There’s more detail, a lot more detail. the image we get is something like 50 times finer than what you get with a single mirror conventional telescope. so why is that important? now think back a minute. A couple weeks ago, we looked at castor in the gemini constellation. what do you remember about that? well, through our telescope here, a conventional telescope, castor looked like a single star, but you told us that it wasn’t.

It’s actually six stars orbiting a kind of dancing around each other. Oh, I get it. and an interferometer would be able to see six separate stars. yes. remember, single stars like our sun are the exception, not the rule. so more often than not, you have 23 or more stars clustered around each other, like COSTA. not only that, but even a stars dimensions, a conventional telescope won’t tell you, you can’t determine the stars dimension, because you can’t tell exactly how far away it is. and there are other things as well. how do stars behave as the age? Why do they cluster together?

what was our son like in the past? can we predict giant flares or periods of dimming an interferometer, as will certainly help us find planets? and of course the more planets you find, the greater the possibility of finding planets that may support life. so do you think inter for amateurs will have the kind of impact the hooker telescope had? I doubted. remember, Big Bang was a really revolutionary theory. but then again, if an interferometer is used to locate a planet that supports life, well, that’s another story altogether.

go out for 12 hours in Quebec, Canada.