WEBVTT - Looking Through Telescopes: Part 1 0:00:00.160 --> 0:00:07.200 Brought to you by Toyota. Let's go places. Welcome to 0:00:07.400 --> 0:00:14.360 Forward Thinking. Hey there, and welcome to Forward Thinking, the 0:00:14.440 --> 0:00:16.919 podcast that looks at the future and says, I'm just 0:00:17.040 --> 0:00:20.480 an average man with an average life. I'm Jonathan Strickland, 0:00:20.600 --> 0:00:23.560 and I'm Joe McCormick. And our other host, Lauren Bigelbaum 0:00:23.760 --> 0:00:25.800 is not with us today. She is under the weather, 0:00:25.880 --> 0:00:27.840 but we hope she feels better soon and she'll be 0:00:27.920 --> 0:00:32.720 joining us again in the next podcasting session. Yep, so, Joe, Uh, 0:00:32.920 --> 0:00:36.640 I wanted to look ahead at the next video that 0:00:36.680 --> 0:00:40.479 will be coming out. This podcast will be accompanying it. 0:00:40.840 --> 0:00:44.199 And when I look ahead and try and get a 0:00:44.280 --> 0:00:49.519 closer look, I see that's about telescopes. That was so 0:00:49.720 --> 0:00:53.440 in artful and crass. I tried the same joke when 0:00:53.479 --> 0:00:56.400 we talked about spectrum crunch, but it totally didn't translate then. 0:00:56.520 --> 0:00:58.920 So it's much better in this sense. You're not even 0:00:58.960 --> 0:01:00.920 getting a pity chuck a lot of Now that's fair. 0:01:00.960 --> 0:01:02.720 I don't I don't expect it. Well, we're going to 0:01:02.840 --> 0:01:06.040 talk about telescopes today. Yeah, we're actually we're actually going 0:01:06.080 --> 0:01:08.319 to be covering this in a pair of episodes because 0:01:08.440 --> 0:01:10.560 it turned out as we did more and more research 0:01:11.160 --> 0:01:14.440 that it was a huge topic. So in this episode 0:01:14.440 --> 0:01:17.280 we're really looking at the development of the telescope and 0:01:17.360 --> 0:01:21.080 some of the really cool facilities around the world and 0:01:21.120 --> 0:01:25.399 sometimes outside of the world, orbiting around in other places 0:01:25.440 --> 0:01:28.160 that are are really pushing the boundaries of science. And 0:01:28.200 --> 0:01:32.080 in our second episode will really focus on some future 0:01:32.240 --> 0:01:36.119 up and coming telescopes that are going to really expand 0:01:36.200 --> 0:01:39.520 our our knowledge of astronomy and cosmology. Yeah, so I 0:01:39.560 --> 0:01:41.840 haven't a little bit of an intro for this one. Okay, 0:01:41.920 --> 0:01:45.560 is starting it off? All right? We're city dwellers, are you? 0:01:45.640 --> 0:01:49.200 And I and nol also here with us. We're all 0:01:49.200 --> 0:01:51.800 city dwellers around here, and I imagine a lot of 0:01:51.800 --> 0:01:54.720 our listeners are city dwellers because we I believe we've 0:01:54.720 --> 0:01:56.280 gotten to the point where most of the people on 0:01:56.280 --> 0:01:59.440 Earth are city dwellers now to UN data, Yeah, the 0:01:59.440 --> 0:02:01.960 the popular Asian density is greater in the like there 0:02:02.120 --> 0:02:05.520 there are more people in urban areas, whether that's within 0:02:05.560 --> 0:02:09.280 a city or a metropolitan area as Atlanta is often described. 0:02:10.000 --> 0:02:12.280 Is it? I believe it now, I'm just shooting from 0:02:12.280 --> 0:02:14.120 the hip. I believe this is correct. I think the 0:02:14.200 --> 0:02:17.800 UN estimated that by about seventy percent of the people 0:02:17.800 --> 0:02:21.680 in the world living in cities. But you know what 0:02:21.720 --> 0:02:25.360 that means, more and more people every year are suffering 0:02:25.800 --> 0:02:28.880 from light pollution. Yeah, this is which means they can't 0:02:28.880 --> 0:02:31.359 see the stars as well. If you go out at night, 0:02:31.840 --> 0:02:37.119 you are robbed of the opportunity to see something truly astounding, 0:02:37.200 --> 0:02:41.160 which our ancient ancestors saw every night of their lives. Yeah, 0:02:41.200 --> 0:02:46.679 if you ever see, like, there's some great photography exhibits 0:02:46.680 --> 0:02:50.400 out there, some great photographers who have gone to places 0:02:50.480 --> 0:02:54.760 that have almost zero light pollution and captured some truly 0:02:54.880 --> 0:02:58.600 phenomenal images of the night sky, including seeing that the 0:02:58.639 --> 0:03:01.640 cloudy scatter, heard stars of the Milky Way, you know, 0:03:01.680 --> 0:03:04.840 the things that you might thought at first, is that 0:03:05.320 --> 0:03:08.280 some sort of you know, gas that's been omitted by 0:03:08.280 --> 0:03:11.720 a star. No, those are billions of stars out there 0:03:11.760 --> 0:03:16.080 that are making up that cloud and it's this gorgeous view. 0:03:16.200 --> 0:03:18.919 But for us in the city, we often can't see 0:03:18.960 --> 0:03:20.400 that sort of stuff. In fact, I get to the 0:03:20.400 --> 0:03:23.840 point where where I go up to try and see 0:03:24.360 --> 0:03:28.360 meteor showers whenever those are are you know, forecast, and 0:03:28.720 --> 0:03:30.680 I'm lucky if I can see two or three even 0:03:30.680 --> 0:03:32.840 in a heavy meteor shower, because the light pollution is 0:03:32.880 --> 0:03:35.040 so great that you know, it washes out the sky. 0:03:35.120 --> 0:03:37.400 Last year, I went out to rural Oregon in this 0:03:37.440 --> 0:03:41.640 place that was ten billion miles from the New I mean, 0:03:42.120 --> 0:03:46.880 a Starbucks was was major metropolitan for this place. Um. 0:03:47.240 --> 0:03:50.120 I was out in the woods and the mountains, nothing nearby, 0:03:50.400 --> 0:03:54.080 and I looked up at night, and I don't want 0:03:54.080 --> 0:03:58.240 to wax sentimental, but it was astounding. It was stunning 0:03:58.840 --> 0:04:02.320 looking at the universe. I would stand outside at night 0:04:02.360 --> 0:04:05.120 for you know, ten minutes, just staring up until my 0:04:05.240 --> 0:04:09.160 neck hurt. It was so amazing. And then I started 0:04:09.200 --> 0:04:14.320 thinking about how there were hundreds and hundreds of years 0:04:14.680 --> 0:04:19.920 when that's exactly what the cutting edge astronomers did before 0:04:20.000 --> 0:04:25.719 we had telescopes. Astronomers were naked eye astronomers, so they 0:04:25.800 --> 0:04:28.120 were looking up at that and not just having the 0:04:28.120 --> 0:04:32.799 opportunity to be amazed by it, but actually charting what 0:04:32.839 --> 0:04:36.520 was up there and trying to determine things about the 0:04:36.560 --> 0:04:39.680 movements of the heavens without the aid of a telescope. 0:04:39.920 --> 0:04:43.240 I can't even begin to imagine how someone would do that. 0:04:43.360 --> 0:04:46.640 It's just to me, it's a mess. Of beauty. It's 0:04:46.680 --> 0:04:50.159 not something that could really be studied in a quantitative way. 0:04:50.560 --> 0:04:54.760 It was also what was really messing with people's lives 0:04:54.760 --> 0:04:57.760 because as they started making these observations that realized that 0:04:58.160 --> 0:05:01.960 it started to conflict with some the commonly held views 0:05:02.040 --> 0:05:06.040 of what the Earth and its place in the galaxy 0:05:06.080 --> 0:05:08.360 the universe really is, and they said, well, you know what, 0:05:08.400 --> 0:05:10.680 this doesn't really work the way we think it works. 0:05:10.720 --> 0:05:14.599 That's I don't well, that's one of the other things 0:05:14.600 --> 0:05:16.479 I want to talk about in this episode. So I 0:05:16.480 --> 0:05:18.919 think we should talk now about the history of telescopes. 0:05:19.040 --> 0:05:22.880 But one thing I want to make clear here is 0:05:22.920 --> 0:05:27.480 that telescopes are for more than just esthetic purposes. They 0:05:27.480 --> 0:05:30.560 are for more than just creating beautiful pictures, though they 0:05:30.600 --> 0:05:33.120 do do that. I mean, if you look at images 0:05:33.160 --> 0:05:35.840 generated by the Hubble telescope, many of them are are 0:05:36.520 --> 0:05:40.760 deeply mysterious and powerful and breathtaking. But they're also full 0:05:40.839 --> 0:05:44.279 of data, and they're full of data that can change 0:05:44.440 --> 0:05:47.840 our idea of our place in the universe. So let's 0:05:47.880 --> 0:05:50.680 go way back. Okay, the first telescopes were based on 0:05:50.839 --> 0:05:53.640 just focusing lenses, and in fact, people have been making 0:05:53.760 --> 0:05:56.560 lenses for longer than I realized when I first started 0:05:56.560 --> 0:05:59.960 looking into this. Uh. In the British Museum there's an 0:06:00.040 --> 0:06:03.800 artifact known as the Nimrood lens or the Layard lens, 0:06:03.839 --> 0:06:07.000 which was found in northern Iraq and dated between seven 0:06:07.080 --> 0:06:10.760 fifty two seven ten b c E. That's like a 0:06:10.880 --> 0:06:14.599 twenty seven hundred year old lens. Yeah, that's much older 0:06:14.640 --> 0:06:19.000 than what I had anticipated. It didn't have much magnification power, 0:06:19.160 --> 0:06:22.200 but it could have been used as a crude magnifying glass, 0:06:22.200 --> 0:06:23.839 and you can kind of see how even a very 0:06:23.920 --> 0:06:27.160 basic magnifying glass could have been useful in ancient Assyria. 0:06:27.320 --> 0:06:30.839 Say if all you had was this to provide slight 0:06:30.920 --> 0:06:34.039 aid to ascribes failing eyesight, or even to help start 0:06:34.080 --> 0:06:37.240 a fire with the sun by focusing the sun's rays. 0:06:37.279 --> 0:06:40.560 But by the early sixteen hundreds, that's when things started 0:06:40.600 --> 0:06:44.640 getting really interesting in telescope making. So if you go 0:06:44.680 --> 0:06:46.960 back to Europe at the beginning of the seventeenth century, 0:06:47.480 --> 0:06:51.480 around sixteen o eight or so, at the time, lensmakers 0:06:51.520 --> 0:06:56.800 were beginning to make spy glasses with more powerful refraction lenses, 0:06:56.839 --> 0:07:00.200 and these might double or triple the magnification and of 0:07:00.200 --> 0:07:04.080 an object from a distance. The name, Hans Lippersha gets 0:07:04.080 --> 0:07:06.760 mentioned a lot. He was a lensmaker in the Netherlands 0:07:06.760 --> 0:07:10.160 who tried to file a patent for quote, an instrument 0:07:10.280 --> 0:07:14.200 for seeing at a distance. It's kind of vague, but 0:07:14.280 --> 0:07:16.920 it's probably not right to say that he's the guy 0:07:17.000 --> 0:07:20.840 who invented the telescope, because it seems like the telescope 0:07:20.880 --> 0:07:23.720 is a device that was made by a lot of 0:07:23.760 --> 0:07:26.800 people around the same time. It was sort of a 0:07:26.840 --> 0:07:31.280 trend catching on and lensmakers started producing them at this time. Joe, 0:07:31.360 --> 0:07:34.239 hang on a minute. I remember from the documentary Robin 0:07:34.320 --> 0:07:38.880 Hood Prince of Thieves that uh spyglass was made away 0:07:39.000 --> 0:07:43.120 wrapping a couple of orbs in a leather uh leather 0:07:43.520 --> 0:07:46.280 length of cloth and holding it up and that was 0:07:46.680 --> 0:07:52.400 that had to be what like, that's your figures are 0:07:52.480 --> 0:07:55.920 all wrong according to Hollywood. Well, I wouldn't dispute Robin 0:07:55.960 --> 0:08:01.920 Hood Prince of Dave's no in that accent. He didn't 0:08:01.920 --> 0:08:04.360 even try and the scene, yeah, you know, it's it's 0:08:04.400 --> 0:08:09.280 every other scene obviously obviously that that depiction is not 0:08:09.600 --> 0:08:13.520 really correct. That's that was something that was done in Hollywood. Well, 0:08:13.560 --> 0:08:17.960 another common misconception is that Galileo invented the telescope. I'm 0:08:17.960 --> 0:08:20.360 sure you've heard the case. No, it's not true at all. 0:08:20.680 --> 0:08:24.080 But he made very important improvements to the telescope, and 0:08:24.160 --> 0:08:27.240 he was the first person to do something really interesting 0:08:27.360 --> 0:08:30.240 with the telescope. Did he turn it around and say, 0:08:30.280 --> 0:08:34.400 now you're really tiny? Okay, Well that we have no 0:08:34.520 --> 0:08:37.839 evidence he didn't, So let's assume he did the first 0:08:37.880 --> 0:08:40.959 interesting thing I did with the telescope. Okay, So around 0:08:40.960 --> 0:08:45.199 this time, like sixteen o nine, Galileo Galilei was a 0:08:45.280 --> 0:08:50.120 mathematics professor at Padua, and he was a partisan of 0:08:50.400 --> 0:08:53.480 Copernican heliocentrism. So this is the idea that came from 0:08:53.559 --> 0:08:57.320 the Polish astronomer Nicolas Copernicus, and it said that the 0:08:57.360 --> 0:09:00.880 planets in our solar system all revolved around the Sun, 0:09:01.120 --> 0:09:04.840 as opposed to revolving around the Earth. It's right. The 0:09:05.000 --> 0:09:09.080 dominant thinking in Europe at the time was Aristotle's geocentrism, 0:09:09.120 --> 0:09:13.040 which had two big things going for actually had several 0:09:13.040 --> 0:09:16.000 big things going for it. One of them was just intuition. 0:09:16.440 --> 0:09:18.840 I mean, it's it seems obvious the Earth doesn't seem 0:09:18.920 --> 0:09:21.480 to move. It seems like this is the earth, the 0:09:21.480 --> 0:09:23.880 ground below you is what's fixed. And if you look up, 0:09:23.920 --> 0:09:26.680 it's in the night. You can see things moving around, 0:09:27.000 --> 0:09:29.200 and the sun comes up on one side, goes down 0:09:29.200 --> 0:09:31.520 on the other. The moon comes up the same way 0:09:31.520 --> 0:09:33.480 and goes down the same way. So you figure, oh, 0:09:33.520 --> 0:09:38.440 there's this revolving skylight that's above me, and where I 0:09:38.480 --> 0:09:43.199 am is fixed and permanent. Yeah. So Aristotelian geocentrism is 0:09:43.240 --> 0:09:46.240 one of those false facts that's just common sense. I mean, 0:09:46.280 --> 0:09:50.760 it seems completely obvious, but turns out it's wrong. So 0:09:51.040 --> 0:09:53.280 it was the dominant thinking in Europe at the time, 0:09:53.320 --> 0:09:56.280 and it also in its favor, it had the fact 0:09:56.320 --> 0:09:59.480 that some people interpreted passages in the Bible to support 0:09:59.480 --> 0:10:03.880 geo center rhysm uh and that also it was Aristotle's view, 0:10:03.920 --> 0:10:05.880 which at the time and it might as well have 0:10:05.960 --> 0:10:09.800 been the Bible because Aristotle was highly hallowed. In fact, 0:10:09.800 --> 0:10:12.520 it might have been egocentric and not geocentric at that point. 0:10:13.559 --> 0:10:16.360 So being a supporter of heliocentrism at the time was 0:10:16.400 --> 0:10:20.400 a really tough road, yes, especially if you had, you know, 0:10:20.520 --> 0:10:23.679 some pretty powerful representatives of the Church who felt that 0:10:23.679 --> 0:10:28.240 that was harmful to their view of the world. Yeah, 0:10:28.240 --> 0:10:31.320 and so when Galileo learned about the telescope in sixteen 0:10:31.320 --> 0:10:33.960 o nine. He was like, ah, I'm gonna get my 0:10:34.000 --> 0:10:36.800 hands on one of these, So he decided to make 0:10:36.840 --> 0:10:40.320 his own, and he started building more and more powerful models. 0:10:40.320 --> 0:10:43.800 He eventually had a telescope of about eight times magnification, 0:10:44.120 --> 0:10:49.439 then later thirty times, and back then that was some incredible, 0:10:49.679 --> 0:10:53.199 pretty unprecedented power. So in the winter of sixteen o 0:10:53.320 --> 0:10:56.760 nine to sixteen ten, he used his thirty x magnification 0:10:56.800 --> 0:11:00.760 telescope to look at objects in the sky, and he 0:11:00.800 --> 0:11:03.559 described what he saw in a treatise, a little book 0:11:03.640 --> 0:11:08.439 called the Starry Messenger or the Starry Message. Just one 0:11:08.440 --> 0:11:11.480 of the observations he saw was about the planet Jupiter, 0:11:12.520 --> 0:11:15.360 and so he looked up and lined up around Jupiter. 0:11:15.440 --> 0:11:19.360 Galileo saw a little stars. But then when he observed 0:11:19.440 --> 0:11:22.880 Jupiter again later, he realized those same three little stars 0:11:22.960 --> 0:11:27.000 were in different places. They were orbiting the planet Jupiter. 0:11:27.440 --> 0:11:31.400 He was seeing Jupiter's moons for the first time anybody has. 0:11:31.559 --> 0:11:35.200 So now he's seeing a body that's revolving around another body, 0:11:35.400 --> 0:11:39.600 not revolving around the Earth. So so now the Earth 0:11:39.720 --> 0:11:43.520 is no longer special because they can see another planet 0:11:43.520 --> 0:11:46.400 where the same thing is happening there, exactly right. He 0:11:46.600 --> 0:11:51.000 also observed the phases of Venus. So just like the moon, 0:11:51.120 --> 0:11:54.280 which has phases, you know that Venus also has phases. 0:11:54.840 --> 0:11:57.960 And the phases of Venus seemed to indicate that Venus 0:11:58.040 --> 0:12:01.840 had its own independent orbit around its source of illumination, 0:12:02.240 --> 0:12:05.360 the Sun. Well, how could that be the case if 0:12:05.559 --> 0:12:10.120 the Sun and Venus both orbited the Earth. So this 0:12:10.200 --> 0:12:13.760 was some of the early evidence that geocentrism really didn't 0:12:13.800 --> 0:12:18.360 hold water. And finally here heliocentrism one the day. Well, 0:12:18.400 --> 0:12:21.840 actually it didn't immediately now, there was some there were 0:12:21.880 --> 0:12:24.520 some critics. Yeah, of course, Yeah, the debate was not 0:12:24.640 --> 0:12:28.160 immediately settled, and Galileo had some troubles with the Roman 0:12:28.200 --> 0:12:32.760 inquisition his his works. He was forbidden from teaching his 0:12:32.920 --> 0:12:36.680 theories and his works were widely banned, and eventually years 0:12:36.760 --> 0:12:39.160 later he was condemned to house arrest for the rest 0:12:39.240 --> 0:12:41.520 of his life. And it's kind of a sad story. 0:12:41.880 --> 0:12:46.720 But in the end, especially when Newton came along, helio 0:12:46.760 --> 0:12:49.600 centrism was finally like, okay, we're starting to understand how 0:12:49.640 --> 0:12:54.280 gravity works. And it's clear now that helio centrism is 0:12:54.320 --> 0:12:56.720 the correct view. And so this is just one of 0:12:56.720 --> 0:13:01.720 those early stories about how telescopes aren't just pretty, they're 0:13:01.720 --> 0:13:05.880 not just nice things. It's not just something about the universe. 0:13:05.960 --> 0:13:07.960 It's not just something that lets us get a look 0:13:08.120 --> 0:13:10.720 at an object that's further away than what we can 0:13:10.760 --> 0:13:14.559 normally see with naked eye. It actually has helps us 0:13:15.320 --> 0:13:19.480 reason out how the universe works. And in fact, we're 0:13:19.520 --> 0:13:21.840 gonna be talking about a lot of telescopes that have 0:13:22.440 --> 0:13:29.280 revealed some phenomenally important information as far as our understanding 0:13:29.280 --> 0:13:31.840 of the universe goes. It might be something that you 0:13:31.840 --> 0:13:33.600 know on your day to day life, it doesn't seem 0:13:33.640 --> 0:13:35.360 like it's that big a deal, but it really does 0:13:35.440 --> 0:13:38.760 mean that we are slowly peeling back the layers of 0:13:38.840 --> 0:13:42.400 mystery around our universe to get a better understanding of 0:13:42.440 --> 0:13:46.120 how it started, when it started, how it evolved, and 0:13:46.640 --> 0:13:50.160 ultimately that kind of leads to our place in the universe. 0:13:50.559 --> 0:13:54.240 And so in this way, I think telescopes are one 0:13:54.280 --> 0:13:58.880 of the most important tools, maybe along with particle accelerators, 0:13:59.679 --> 0:14:05.560 for understanding the most basic, most fundamental facts about what 0:14:05.760 --> 0:14:09.600 exists and where we are in it and uh and 0:14:09.600 --> 0:14:14.559 and telescopes have evolved significantly since their introduction to the 0:14:14.600 --> 0:14:19.040 point where they are no longer necessarily limited to just 0:14:19.480 --> 0:14:23.640 the visible spectrum of light, which is what well, right, 0:14:23.680 --> 0:14:27.880 So we started with these refraction lenses, which means clear 0:14:28.040 --> 0:14:32.600 transparent glass lenses that were like the old spy glass. 0:14:32.640 --> 0:14:35.280 So it's a curved lens that gathers a two dimensional 0:14:35.320 --> 0:14:38.360 scrap of light, magnifies it by a certain multiplier, and 0:14:38.360 --> 0:14:40.920 passes it along to your eye. But now we we 0:14:41.000 --> 0:14:43.840 have other types of telescopes that look at other parts 0:14:43.840 --> 0:14:45.840 of the visible spectrum, and we have other types of 0:14:45.880 --> 0:14:50.359 optical telescopes that are more powerful. We also have reflection telescopes, 0:14:51.080 --> 0:14:54.200 and so these came a little later that they're used mirrors. 0:14:54.920 --> 0:14:58.200 The most powerful optical telescopes, like the ones you used 0:14:58.200 --> 0:15:01.360 to see some pretty real stuff in space. These are 0:15:01.600 --> 0:15:05.520 pretty much all going to be reflecting telescopes made with mirrors. Yeah. 0:15:05.560 --> 0:15:08.880 The largest one on Earth right now as the recording 0:15:08.920 --> 0:15:13.720 of this podcast, is the Grand Telescopio Canarias a k a. 0:15:13.920 --> 0:15:17.960 The GtC, and now it has an effective light collecting 0:15:18.040 --> 0:15:23.040 surface of seventy three square meters. That's that's if you 0:15:23.480 --> 0:15:27.680 factor in the entire surface of the of the lens itself. Yeah, 0:15:27.720 --> 0:15:30.680 it's pretty big the now when you're looking at the 0:15:30.680 --> 0:15:34.760 primary mirror, it's not seventy three meters across or anything. 0:15:34.760 --> 0:15:37.000 It's like ten point four meters across something like that, 0:15:37.080 --> 0:15:40.520 But it's still pretty huge. The primary mirror has thirty 0:15:40.600 --> 0:15:44.400 six hexagonal segments that collectively act as a single mirror. 0:15:44.680 --> 0:15:48.160 The entire telescope ways about seventeen tons. It's located on 0:15:48.200 --> 0:15:50.560 top of a volcanic peak in the Canary Islands, which 0:15:50.600 --> 0:15:52.760 is off the coast of Spain. I assume an active 0:15:52.840 --> 0:15:57.360 volcano peak actively active, like there's lava being thrown up 0:15:57.360 --> 0:15:59.920 all the time while people are are are shouting fights 0:16:00.400 --> 0:16:03.040 on the top of the mirrors. You have a very 0:16:03.080 --> 0:16:05.960 interesting view of what modern Spain must be like. No, 0:16:06.160 --> 0:16:08.400 I just have an interesting view of telescopes. I see 0:16:08.440 --> 0:16:11.040 them in a heroic content. Okay, alright, right, because we've 0:16:11.080 --> 0:16:12.920 got pirates and all that kind of stuff too, you know, 0:16:13.240 --> 0:16:15.840 that's shaped our view. But anyway, it is the largest 0:16:15.960 --> 0:16:20.360 current optical telescope on Earth. Yeah, but I think we 0:16:20.360 --> 0:16:24.280 should also focus attention on the non optical telescopes, the 0:16:24.280 --> 0:16:26.880 ones that are not for visible light but for other 0:16:27.040 --> 0:16:31.560 parts of the electromagnetic spectrum. So light, as we've talked 0:16:31.600 --> 0:16:34.520 about before, is just one part of the e M spectrum. 0:16:34.560 --> 0:16:38.240 It starts with very long radio waves, it goes on 0:16:38.360 --> 0:16:40.040 up to light, and then up and up and up, 0:16:40.080 --> 0:16:42.680 and you end with gamma waves, gamma rays that are 0:16:43.360 --> 0:16:47.880 very high energy, very short frequency waves, short wavelength, high 0:16:47.920 --> 0:16:52.520 frequency short sorry, high frequency, short wavelength, Thank you for correcting. 0:16:52.600 --> 0:16:55.320 No worries, No worries. No. When we talk about radio telescopes, 0:16:55.320 --> 0:16:57.880 obviously we're talking about radio waves. These are those longer 0:16:57.920 --> 0:17:00.960 waves you were alluding to just a second ago. These waves, 0:17:01.240 --> 0:17:04.320 the wavelengths can be like more than a kilometer long, 0:17:04.400 --> 0:17:07.680 so we're talking huge wavelengths. But wait a minute, Jonathan, 0:17:07.960 --> 0:17:10.479 why would you use a Why would you point a 0:17:10.560 --> 0:17:14.440 radio receiver at space unless you're listening for aliens beaming 0:17:14.520 --> 0:17:18.480 radio signals at you. Well, for one thing, you cannot 0:17:18.560 --> 0:17:22.240 discount the power of picking up some really awesome tunes. 0:17:23.080 --> 0:17:27.240 But no, to be more serious, a radio telescope array 0:17:27.480 --> 0:17:30.040 is really it's meant to detect the presence of radio 0:17:30.080 --> 0:17:34.040 waves and extraterrestrial radio waves specifically, because if you're just 0:17:34.080 --> 0:17:37.160 detecting terrestrial ones, then there's no big deal. That's that's 0:17:37.200 --> 0:17:42.160 coming from Earth. Extraterrestrial, but not necessarily meaning extraterrestrial life, right. 0:17:42.240 --> 0:17:44.920 Extraterrestrial just means it comes from outside the Earth. It 0:17:44.960 --> 0:17:48.200 does not necessitate that there's some sort of alien life 0:17:48.240 --> 0:17:50.720 form generating those radio waves, because, as it turns out, 0:17:51.480 --> 0:17:54.560 lots of stuff generates radio waves, like the Sun generates 0:17:54.720 --> 0:17:59.200 radio waves, you know, nebula generate radio waves, super nova 0:17:59.400 --> 0:18:01.840 you know. Also sorts of events in space can generate 0:18:01.920 --> 0:18:05.520 radio waves. So by detecting them, we can detect things 0:18:05.600 --> 0:18:10.399 like the the presence of what was a new star, 0:18:10.800 --> 0:18:13.399 for example, in a particular sector of space. Now granted, 0:18:13.760 --> 0:18:16.399 by the time we detected it may very well be 0:18:16.680 --> 0:18:19.080 depending upon the distance from the Earth, that new star 0:18:19.359 --> 0:18:22.639 is well into middle age or even older. Uh. It 0:18:22.680 --> 0:18:25.639 all depends upon you know, what sector of space and 0:18:25.680 --> 0:18:29.639 how strong was the signal. So uh. In order to 0:18:29.800 --> 0:18:33.399 get these radio waves, to detect them, you usually have 0:18:33.440 --> 0:18:36.159 an array of telescopes, meaning that there are there's a 0:18:36.160 --> 0:18:38.920 collection of them, it's not just a single telescope. Also, 0:18:39.400 --> 0:18:41.800 they tend to look like satellite dishes, you know, like 0:18:41.840 --> 0:18:44.479 the old satellite dishes you would put. Um. You might 0:18:44.520 --> 0:18:48.040 even have one if you have satellite television where the 0:18:48.080 --> 0:18:51.480 parabolic shape and then you have the focus point where 0:18:51.480 --> 0:18:54.360 the antenna is. Uh, that's exactly what it's for there. 0:18:54.440 --> 0:18:58.080 The parabolic shape is meant to uh to focus those 0:18:58.200 --> 0:19:01.200 incoming radio waves specifically on the point of the antenna 0:19:01.359 --> 0:19:04.080 so that you can detect even the faintest signals. And 0:19:04.119 --> 0:19:08.680 you have an array of them to increase your detection area. 0:19:08.920 --> 0:19:12.240 So these like you can essentially think of an array 0:19:12.359 --> 0:19:17.600 as making up individual components of an overall huge radio 0:19:17.800 --> 0:19:21.280 telescope antenna. So they're all working together to do this 0:19:21.920 --> 0:19:24.719 and uh, the very first one was built seven by 0:19:24.720 --> 0:19:29.040 Groat Reaber in the United States. Today you often will 0:19:29.080 --> 0:19:33.679 find them with cryogenically cooled solid state amplifiers. The purpose 0:19:33.720 --> 0:19:36.840 for that is to reduce any kind of internal interference 0:19:36.920 --> 0:19:40.320 that you might get. Clearly, any kind of electromagnetic interference 0:19:40.400 --> 0:19:42.960 could create a false positive, so you want to cut 0:19:42.960 --> 0:19:44.600 down on that as much as possible. Yeah, I mean, 0:19:44.920 --> 0:19:47.080 these kind of things are a problem because the signals 0:19:47.080 --> 0:19:51.280 we received from space are very faint in relationship to 0:19:51.320 --> 0:19:54.000 the kinds of signals that are generated all the time 0:19:54.040 --> 0:19:56.760 on Earth. I remember reading a long time ago for 0:19:56.800 --> 0:19:58.840 a blog post I wrote, I think it was that 0:19:59.760 --> 0:20:03.360 they clear radio astronomers would say that if you had 0:20:03.359 --> 0:20:06.160 a cell phone and you were standing on the surface 0:20:06.160 --> 0:20:08.880 of the Moon and you started making a call there, 0:20:09.400 --> 0:20:13.240 that would generate a signal that radio astronomers would consider 0:20:13.359 --> 0:20:16.639 really strong. Yeah, it would also probably you know, be 0:20:16.680 --> 0:20:18.879 the last call you made, unless you happen to be 0:20:18.920 --> 0:20:22.440 wearing a space suit. Because conditions on the Moon are terrible. 0:20:22.760 --> 0:20:25.160 Why would I not happen to be wearing a space suit? 0:20:25.240 --> 0:20:29.280 Because how do you activate your touch sensitive phone? Confidence 0:20:29.280 --> 0:20:32.040 in and I think ahead, come on, if you're using 0:20:32.040 --> 0:20:34.879 a capacitive touchscreen smartphone, then you're not going to be 0:20:34.920 --> 0:20:39.200 able to activate it through the materials special gloves. Okay, well, 0:20:39.440 --> 0:20:42.159 clearly you've thought. Okay, let's talk about other types of 0:20:42.160 --> 0:20:46.480 telephones telephones, thank God. Before we do that, let me 0:20:46.520 --> 0:20:49.919 also say this, um, yeah, that if you if you 0:20:49.960 --> 0:20:53.000 ever look at at the location of these they tend 0:20:53.000 --> 0:20:56.919 to be very far away from areas of heavy populations 0:20:57.040 --> 0:20:59.000 to try and cut down on as much of that 0:20:59.080 --> 0:21:01.960 interference as possible. And they also tend to be in 0:21:02.080 --> 0:21:05.200 areas that may have very tight restrictions on the sort 0:21:05.240 --> 0:21:09.280 of uh of of of operations. That can happen in 0:21:09.280 --> 0:21:11.040 that area. Yeah, you don't want to build a cell 0:21:11.080 --> 0:21:13.440 tower next to them. Yeah, that would be that would 0:21:13.520 --> 0:21:17.280 not be conducive to trying to detect extraterrestrial radio waves. 0:21:17.440 --> 0:21:20.240 But yes, there are other types too. There's infrared telescopes, 0:21:20.400 --> 0:21:23.560 which you know, now we're getting closer to the visible spectrum, 0:21:23.600 --> 0:21:25.399 but it's still outside of it. We can't see an 0:21:25.400 --> 0:21:29.440 infrared right. But the cool thing about infrared is anything 0:21:29.520 --> 0:21:33.919 that has temperature above absolute zero generates infrared radiation. Yeah, 0:21:34.000 --> 0:21:38.840 but the tricky part is anything that zero, So you 0:21:38.880 --> 0:21:40.720 have to you have to figure out how to build 0:21:40.720 --> 0:21:43.640 it so that you can see uh stuff that's not 0:21:44.000 --> 0:21:46.760 um uh, not generated by the Earth. Also, the other 0:21:46.800 --> 0:21:50.920 issue is that water vapor can absorb infrared radiation. So 0:21:51.240 --> 0:21:54.280 you want to make sure you have your infrared telescopes 0:21:54.359 --> 0:21:57.800 located someplace where water vapor is not going to be 0:21:57.840 --> 0:21:59.320 a factor, where you're not going to have all that 0:21:59.440 --> 0:22:01.439 radiation of zorb before you can have a chance to 0:22:01.480 --> 0:22:04.800 really detect it. So most infrared telescopes are at very 0:22:04.880 --> 0:22:09.040 high elevations above the the moisture that you would see 0:22:09.119 --> 0:22:14.199 like a normal weather patterns or in space, and so 0:22:14.280 --> 0:22:18.280 they're looking for stuff like nebula or gas out in space, 0:22:18.440 --> 0:22:20.840 young stars, that kind of thing. They're very similar to 0:22:20.840 --> 0:22:24.480 optical reflecting telescopes, which isn't a big surprise. Now when 0:22:24.520 --> 0:22:27.640 we are looking at images from infrared telescopes, those are 0:22:27.680 --> 0:22:30.320 clearly images where the data has gone through some form 0:22:30.359 --> 0:22:32.800 of transformation, because again, if you were looking at a 0:22:32.840 --> 0:22:35.520 picture of an infrared image, you wouldn't see anything, so 0:22:35.560 --> 0:22:37.240 you have to convert it into visible light that we 0:22:37.240 --> 0:22:40.000 can see. So often if you ever look at images 0:22:40.000 --> 0:22:44.080 from NASA, you'll there's usually a little bit of text 0:22:44.240 --> 0:22:47.199 somewhere in there that talks about the conversion process that 0:22:47.280 --> 0:22:49.360 was made so that we would be able to actually 0:22:49.400 --> 0:22:51.439 see it. You know, this is how it would appear 0:22:51.440 --> 0:22:53.280 to us in the visible spectrum, keeping in mind it 0:22:53.320 --> 0:22:57.240 was detected outside the visible spectrum, so that's something to 0:22:57.240 --> 0:22:59.560 to keep in mind. Then there's some other types too, 0:23:00.040 --> 0:23:01.920 I mean, all along the spectrum. You can look at 0:23:01.960 --> 0:23:05.439 say X rays. Yeah, now these are shorter wavelengths, uh 0:23:05.600 --> 0:23:11.680 than infrared, and you're talking about some serious, uh possibly 0:23:11.760 --> 0:23:14.240 damaging stuff for us for us here on Earth. But 0:23:14.359 --> 0:23:18.240 X ray telescopes obviously are about detecting X rays, not 0:23:18.280 --> 0:23:21.119