M1: Technology is very important in astronomy. It directly affects what we know and how clearly we can understand our universe. In astronomy, the best example of this is the technology of the telescope. First of all, let's begin with the Hooker telescope. I think this was one of the most significant technological evolutions of the telescope. In the 1920s, the Hooker telescope was the most powerful telescope in existence. It enabled scientists to see the Milky Way and to learn that there were countless other galaxies that existed outside of the Milky Way. We learned that the Milky Way was not the only galaxy in the universe. Even that alone was a pretty big discovery. Moreover, the Hooker telescope showed that these other galaxies were moving away from one another. Then why was this significant? Galaxies... are moving away from us...
M2: The Big Bang! That's when people thought of the Big Bang theory, right?
M1: That's right. The Big Bang theory is an absolutely revolutionary theory. We all know this theory that some time about 15 billion years ago, the universe was created in a giant explosion and this caused everything to blow apart in different directions. Well, this is still happening. So, with the advancement of technology, with the Hooker telescope, scientists came up with perhaps the most significant theory about the creation of the universe. And, the general acceptance of this theory quite literally changed the way that humans look at the universe. Okay, so moving on, now I want to focus on something a little more current. It's an interferometer. Can anyone tell me how this device works?
W: Yeah, it is a special kind of large telescope which is linked by 2 or more telescopes together. It catches starlight and then sends that light down to tubes or pipes. The tubes are connected to computers and computers combine all of the images to create one single image.
M1: Yeah, that's about right, but the actual process is a little more complicated than that. The early astronomical interferometer was mostly made of two telescopes to measure the amount of power on a particular small angular scale. Later, it became more complex and consisted of several telescopes, usually identical, arranged in a pattern on the ground. A lot of interferometers use 6 telescopes, and those pipes, you mentioned, could be thousands of meters long. All of those pipes send images back to a computer and then you have to synchronize the images so that the computers show the same thing as the real one, It's a technically tricky and complicated process. So why do we need it? What's the major benefit of interferometers? Do we see farther with them?
M2: Um, it's not so much that we're able to see farther away, but the images that they produce are a lot sharper than those from traditional telescopes, right?
M1: Good answer, absolutely right. Yes, those images are much sharper. In fact, they're up to 50 times sharper than conventional telescopes. The larger the telescope, the better its resolution. The cost of building a telescope also scales with its size though. Okay, then why is having very sharp pictures so important? Well, last week we observed Castor in the Gemini constellation. From the traditional telescope here, Castor looked like a fuzzy star, But, with an interferometer, we could be able to see that Castor is actually made up of 6 stars orbiting one another much like a wild dance. Remember, our single sun is not the rule; it's rather an exception. In
the universe, there are a lot of stars that are actually 2, 3, or more stars orbiting one another.
Now, here's my point; having the ability to observe stars means that we can also find more planets. This is a pretty obvious benefit that we can get when we employ more advanced telescopes. With the interferometer, we can get very accurate images of things that
were previously blurry or unclear. It's easier for us to identify more planets, even some that we may have missed using conventional telescopes. Besides, the more planets we find, the higher the chance that we may actually be able to find a planet that has some life on it. Even if the planet does not have intelligent life, just the discovery of a planet that has very basic life will be an incredible discovery itself.
M2: Wait, so you think that the Hooker telescope is less significant than the interferometer?
M1: No, keep in mind that without the Hooker telescope, we would have discovered neither the Milky Way nor the expanding galaxy which gave us a new perspective about the universe. So far anyway, the Big Bang theory has entirely changed the way we look at
everything in the universe. But I mean, if we were to find a planet that actually had life on it while using an interferometer, then it would be a whole other story altogether.