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Exploring 400 Years of the Telescope


Aired 4/9/09

2009 is the International Year of Astronomy for good reason - it's the 400 anniversary of the telescope. We'll talk about the history of the telescope and its impact on astronomy, as well as modern attempts to understand the universe.

Video unavailable. Read transcript below.

Above: Scientists at the Palomar Observatory, in collaboration with international partners, are embarking on a five-year observing project expected to unveil types of astronomical objects that have never been observed before.

MAUREEN CAVANAUGH (Host): I'm Maureen Cavanaugh, and you're listening to These Days in San Diego. For all the star-gazing and star-mapping that went on in early civilizations, it's only been about 400 years that we've been able to get a good look at heavenly objects. And the reason for that is the invention and refinement of the telescope. From a three-lens spyglass to today's huge space observatories, the telescope has opened our eyes to the universe. To help celebrate 2009 as the International Year of Astronomy, a new documentary about the telescope will air on KPBS Television Monday night. It’s called “400 Years of the Telescope: A Journey of Science, Technology and Thought.” The show’s producer, Kris Koenig, is here to talk about it. Welcome, Kris. Hi, Kris?

KRIS KOENIG (Documentary Producer): Yes, hello.


KOENIG: Thank you.

CAVANAUGH: And in any discussion about telescopes here in San Diego, we could never forget our own Palomar Observatory. Scott Kardel, public affairs coordinator for the Palomar Observatory is also here. Welcome, Scott.

SCOTT KARDEL (Public Affairs Coordinator, Palomar Observatory): Hi, Maureen.

CAVANAUGH: Now, Kris, let me start with you and the whole idea of celebrating 400 years of the telescope is because Galileo is credited with being the first person to use a telescope to examine the night sky in the year 1609. But Galileo did not invent the telescope, didn’t he – did he? He sort of reinvented it.

KOENIG: Well, he improved upon it, that’s correct. And the person that gets the credit is a Dutchman named Hans Lippershey and it’s even a question whether he was the first to do it himself but he is the first to apply for a patent. He applied for it in the fall of 1609, actually in the spring of 1609 and by the fall the description of the telescope had made its way down to Italy and Galileo then made his first telescope. But he made it not for star gazing, he actually made it to try to corner the market on ships coming into the ports. He felt that it would be a great tool for commerce, and that was his original goal with it. It wasn’t until the late fall of 1609 that he actually started using it for star gazing and basically set us on this course that we continue today in astronomy.

CAVANAUGH: Tell us a little bit about these first telescopes. What were they like? Were they handheld?

KOENIG: They were. They were handheld as spyglasses but he did build a crude tripod and bracket system to hold his spyglasses, his simple telescopes and, you know, to do – to facilitate his nighttime observing. But they were very difficult to look through. The optical design of Galileo’s first telescopes have a very, what we call, a large exit pupil, so it’s quite a large field of view that you move your eye through and it makes it kind of difficult to look through because it’s kind of – the best way to describe looking through Galileo’s telescope is like looking at a small window at the end of a very long straw.


KOENIG: And the fact that he actually did the observations that he did is a statement of his patience and willingness to continue to observe and reobserve until he got a clear picture of what he was looking at.

CAVANAUGH: Now, for the scientifically challenged, can you explain how a telescope works?

KOENIG: Well, the light is – As the light comes through the lenses, it gets bent or if, in the case of a mirror, it also gets focused to a focal point of which it then is passed through another lens which then magnifies that image, is a very simple description.

CAVANAUGH: So that – and that, I imagine, is how these first telescopes worked.

KOENIG: That is how the first telescopes worked. They were on lenses, they were not mirrors like our modern day observatories.

CAVANAUGH: And so as you describe it, looking through a window through a long straw, what could Galileo see with this instrument?

KOENIG: Well, his picture is very similar to, let’s say, a toy spyglass of today. If you went to the dollar store and you bought a, you know, a one-dollar, two-dollar plastic little spyglass or opera glass would be a better term. It’s a very crude view but it was enough to allow him to realize that there were craters on the moons, that the Milky Way wasn’t a cloud, it was actually made up of billions of stars. And then, of course, the key point was that he observed Jupiter’s moons in orbit around Jupiter and because of that he was able to prove and reinforce Copernicus’ theory that the Earth was not the center of the universe.

CAVANAUGH: And so this, what we would describe as a crude instrument that offered a very limited view of the heavens the way we think of it now with our modern telescopes, really just shook the world, though, in changing what we knew about the solar system and how that information was received by the public and the church.

KOENIG: It – He did. And I think there’s a couple of things that are going on here. First, the Catholic Church was not against his discoveries, his initial looks at the heavens and his, you know, propagandizing what he was seeing. But as people started to think about the implications of it, as they started to think that the Earth was now not the center of the universe, that the sun was, was not a act of, you know, raising the, you know, taking the Earth off of some great point and moving it to a lower statue (sic), it was actually – the Earth was considered the sump pump of the universe, that all the trash fell to Earth including humans and the human spirit. And by displacing that, by moving the Earth out of that section and putting the sun there, that was the issue that the Catholic Church was having at the time. And that’s what eventually became a challenge. The other thing, there was some politics going on, is he had a good friend that he used to sit around the bars and argue cosmology with and that individual ended up becoming the Pope and he wrote a book. He was – actually what got him in trouble. He broke an agreement with the Catholic Church that he wouldn’t propagandize his new views of the heavens and then his friend became the Pope and he thought he could go back to doing his old writings and he wrote a book called “Dialogue Concerning Two Chief World Systems.” And he took the voice of the Pope and gave him the name of Simplicio in this book and the combination of that and the fact that he broke the law, the church law that he had agreed not to go out and postulate his theories of the cosmos anymore, got him in trouble. So it wasn’t the science, it was more politics and, you know, just bad taste of taking what was then a very powerful man and making him look like an idiot.

CAVANAUGH: So it wasn’t the telescope that got him into house arrest for the rest of his life.



KARDEL: …it was his fine personality.

CAVANAUGH: Now, let’s move it along a little bit. Who else is instrumental in advancing this instrument? This telescope since Galileo?

KOENIG: There’s been hundreds of people who’ve, you know, from basically Newton all the way up to Bob O’Dell who is the gentleman who designed the Hubble Space Telescope to others who continue to build great land-based telescopes today. But Newton made a big change. Newton used a mirror instead of a lens to make his telescope which allowed them to make bigger, larger telescopes cheaper and better. The Herschels came along. They’ve improved upon it. And we continue to improve up through the ages. A local boy or obviously a very well known individual in the Southern California area and throughout North America astronomy is obviously Mr. Hale, who basically the – he came out and worked on the Licht Observatory, moved south, did Mt. Wilson and eventually his legacy led to Scott’s telescope there in Palomar.

CAVANAUGH: Yeah, I want to get to that but I want you to tell us, Kris, if you can give us an idea of how different the early telescopes were from the big telescopes used today like the one at Palomar.

KOENIG: There’s really no comparison. When we turn – And at the turn of the century, in the 1900s, we really start making some huge leaps in our technology and our views of the heavens. Up to the 1900s, and the 100-inch at Hale, our views of the universe really didn’t change a lot. We were kind of like stuck in a box and trying to see the universe through cardboard. When we get to the point of the Hale and the 100-inch, we reach a point of light gathering and resolution that we can start seeing stars in other galaxies. And this led to a major expansion in our model of the universe. The next major advance in this whole progress was the detectors, photography and photometry, electronic detectors that came along, improved our ability to gather that light and put it into a recorded media that we could eventually look at and continue to pull information out of. But the real leap of faith was when we launched the Hubble Space Telescope, not leap of faith but leap of knowledge was when we had the Hale – or, excuse me, the Hubble Space Telescope launched and we got this next new picture of the universe. We got to look far enough back in time to start seeing a universe that does not look like the universe we live in today. And we will go through this again as we get these new telescopes that are coming online like the GMT, the Great Magellan Telescope, that’s being built in Chile, the TMT that’s going to go in Hawaii, the Thirty Meter Telescope. When these come online, we’re going to get a whole new picture of the universe and our view of the universe will change. It will change again as drastically as it did at the turn of the century.

CAVANAUGH: I’m speaking with Kris Koenig. He’s the producer of a new documentary airing on KPBS Monday called “400 Years of the Telescope: A Journey of Science, Technology and Thought.” And I’d like to bring my second guest into the conversation right now. Scott Kardel is public affairs coordinator for Palomar Observatory. We spoke a bit about Palomar Observatory. There are actually several different telescopes in use at Palomar, aren’t there?

KARDEL: That’s correct. Yeah, we have – Our first telescope got going actually in 1936 but as the 200-inch telescope neared completion, they finished a wide angle telescope, a Schmidt telescope, and the Schmidt telescope was a very exciting revolution because it allowed astronomers to have this wide view of the sky and it was basically built to map the whole Northern skies. And it began a survey in the 1950s and as improvements have come along the years, it’s still being used for survey work every night.

CAVANAUGH: Now, why was Palomar chosen as the site for this big observatory? I mean, your 200-inch telescope was the biggest telescope for many, many years, in fact most of the 20th century. And I’m wondering why Palomar was chosen.

KARDEL: Well, I think there were four official reasons and an unofficial reason, too. So the official reasons were that Palomar was a site with good, clear skies and a very stable atmosphere so we have a steady view of things. Back in the 1930s when they chose the site, we were in the middle of nowhere. We had very dark skies, which is an essential ingredient, not as dark as they are now. And finally the fourth official reason was it wasn’t too far from Pasadena where the academic base of the observatory at Cal Tech is located. But I think the fifth reason is that George Ellery Hale wanted it there.

CAVANAUGH: And what he wanted, he got.

KARDEL: Hale was a very good persuader of people, talking people out of their money and organizing big projects. And Hale usually got what he wanted, yeah.

CAVANAUGH: You know, I want to take a short break here and I want to continue our discussion about Palomar and especially about this new documentary and about the telescopes that are coming up in the pipeline. You are listening to These Days. We’ll be back in a moment here on KPBS.

CAVANAUGH: Welcome back. You’re listening to These Days. I’m Maureen Cavanaugh. And we’re talking about the “400 Years of the Telescope.” It’s a new documentary produced by my guest, Kris Koenig. And we also have Scott Kardel, who’s talking about the Palomar Observatory here in San Diego. And, Scott, I want you, if you could tell us, what was the process like for building that big telescope at Palomar called the Big Eye.

KARDEL: Take yourself back to the Great Depression. I mean, the money for the observatory was granted just prior to the Great Depression beginning. And there was work taking place on the east coast, in New York where they built the mirror and in Philadelphia where they built the structure of the telescope, by people that were eager to work and with the economy the way it was, they didn’t know if they would ever get another chance to build a big telescope like this again. So the work that was done was done with great care by people that were, you know, very happy to be working on this but also received a tremendous amount of national attention. People could look to this project and say, wow, something good is happening. And, for instance, when the mirror made the trip across country in 1936 by rail, thousands and thousands of people at various stops came out to watch the train car go by. People had to clear the tracks just so that this train car with the words ‘Pyrex 200 Inch Mirror’—because you’ve got to get your advertising on there…


KARDEL: …just to see that. I mean, they didn’t actually see the piece of glass, they didn’t see the finished telescope, but they felt like they were witnessing something big and important going by.

CAVANAUGH: And it continues to be besides a scientific importance, it continues to be a tourist draw.

KARDEL: Yeah, we actually get over 100,000 people a year come up to Palomar. And we give guided tours on the weekends so that people can come in in the daytime—because we’re doing research at night—but…


KARDEL: …in the daytime, to come in and see how the telescope works and talk to someone about how it was built and the scientific mission that we use it for.

CAVANAUGH: Now what role has Palomar played in terms of knowledge about space?

KARDEL: We’ve had a lot of discoveries from Palomar that have been pretty exciting so in addition to the survey that I mentioned earlier, probably one of the famous discoveries from the 200-inch telescope would be these things called quasars. So Kris earlier mentioned that every time there’s been new revolutions in the size of a telescope, there have been discoveries and things that people didn’t anticipate going all the way back to Galileo and going to the ones coming in the future. Quasars were these things that were found that looked kind of like stars in our own galaxy and it was at Palomar they determined that they were, in fact, hugely far away and the early implication was just sort of mind blowing for people because they realized, wow, we’re looking at something clearly at the other end of the universe and it’s bright. And so they had no idea early on what could possibly generate that amount of light to be visible from such a great distance.

CAVANAUGH: That’s amazing. Kris, I want to take you on to the other end of the spectrum, if I can, and talk about the very beginnings of people looking up into space and trying to figure out what was going on up there. We hear an awful lot about ancient civilization star gazing and making star maps. I’m wondering if the telescopic discoveries early on confirmed some of that early astronomy?

KOENIG: No. I mean, there are some – there are some mythology around that the minds were able to actually see the moons of Jupiter with their naked eye and things like that but early astronomy was more of a record keeping, a verification process with these monuments of ongoing cycles of the Earth around the sun and basically the motions of the stars around the Earth based on its rotation. And so we look at things like Stonehenge and think, well, you know, these are great monuments, the mathematics, and it’s just phenomenal but all they were doing is actually just making these indexes for seasons and certain ongoing cyclatory (sic) type of events. The telescope changed that. The telescope allowed us to start to postulate different ideas of how nature works and then make observations to verify those postulations, those hypotheses. So the telescope really did change everything, and it changes the way we see ourselves in the universe. We have gone, in 400 years, from being the center of the universe to now being a small planet around a basic middle-class star in a middle-class galaxy in the universe filled with a hundred billion galaxies. And we’ve also verified just recently that all the matter in the universe, the baryonic matter, the stuff that makes up you and I and the stars and the planets and the galaxies, only constitutes about 4% of the universe. You know, you know, we’re looking at 96% of the universe that’s still unknown to us. We know it’s out there, we can see it’s a fact, but we don’t know what it is. And that’s dark energy and dark matter. So we have come a long way in that 400 years, much more so than we did in the ten or fifteen thousand years leading up to it.

CAVANAUGH: You know, in your documentary, Kris, “400 Years of the Telescope,” I’ve seen some of it and there are some incredibly beautiful pictures of different solar systems and nebulae and stars and it just got me to wondering, how are those pictures created? I mean, does the telescope actually pick up colors or are the colors added to the pictures after the fact?

KOENIG: Well, the colors are actually there. We lose – when you look through a basic amateur telescope, we see basically shades of gray. You might actually, if you’ve got a trained eye and you’ve been observing a lot, you might actually see some shades of red or what – canned colors. But our eye is just not fast enough, fast being optically fast. We can’t capture the colors. So what we do is we photograph it either with film or digitally and when we do that, we run it through filters. We do a RGB, if you do home Photoshop, you probably know a little bit about color and how it works, and light. And we break these up into three different colors, red, green and blue, and we expose the image, you know, the camera to the image for a period of, you know, 30 seconds, a couple of days, whatever the situation is. And then we bring those three images, the red, the green and the blue, and we sandwich them together and you get that color image. And so it’s a composite of those colors, but it is the color that’s there. The color is – it can be slightly manipulated obviously back and forth but the folks that do image processing are try to (sic) bring it to its true of image as possible. Now, on the other hand, we can take the same filter process and different wave lengths of light, we can go to hydrogen or – and different other wave lengths and we can pull out data using that same process. Instead of making a beautiful color picture, we make a false color image and that false color image gives us data that the astronomers then can use to support their theories or observations.

CAVANAUGH: I see. I see what you’re saying. And when we talk about looking through a telescope and just – our eyes not being fast enough to see the color, Scott, I think of the problem that is always talked about in conjunction with Palomar Observatory and that is light pollution. How much does that interfere in your ability to see the sky?

KARDEL: Absolutely. Quite a bit. So as the cities have grown over the years, the number of people and lights and parking lots and things have increased, and it was back in the 1980s that the folks at Palomar and Cal Tech sort of pushed with local governments to try to have lighting ordinances in place in the City of San Diego and San Diego County and in Riverside County and elsewhere. And that would put – or that did put controls in in terms of having closest to the observatory those lights that are sort of orange in color, those low pressure sodium lights. And astronomers really love those because they put out one color and we can filter that out and see everything else that comes in. Also, the other part of it was try to make sure that lights are actually pointed down where people are at instead of misdirected up in the sky which usually is just a total waste of energy.

CAVANAUGH: So have you been able to compensate for the fact that there’s so much light in the sky or is it a continuing problem?

KARDEL: It’s definitely a continuing problem. So there are many people that are either not aware of the lighting ordinance or aware of the fact that their lights do make a difference. And we find that people are just putting in lights just not really thinking about the implications and often they don’t even really think about how to carefully aim the lights so that they’re actually going exactly where they’re needed and not just all over the place.

CAVANAUGH: You know, talking about getting the people – public involved in your observatory efforts and also in the International Year of Astronomy, I’m wondering if there are local events that people can take part in in order to celebrate this International Year of Astronomy?

KARDEL: There are actually lots of star parties that take place in and around the county. I know that Mira Costa College holds star parties. The San Diego Astronomy Association has star parties, these are places where people can go and get their eyes to a telescope…


KARDEL: …which is something I strongly encourage people to do. At the end of this month, Friday and Saturday, on Palomar Mountain but at one of the National Forest Service campgrounds, is something called Explore the Stars, and that’ll run, I think, the 24th and 25th but basically once a month all the way through October, and you can stop in at the campground and on Saturday night someone’s going to give a talk on astronomy and then you can look and see Saturn.


KARDEL: And that’s just a cool thing to do.

CAVANAUGH: And when is it that people can actually visit Palomar Observatory?

KARDEL: Well, we’re open every day…


KARDEL: …from nine to four. At nighttime, not so much because we are basically involved in doing research. But we have the guided tours that people can take Saturdays and Sundays at 11:30, 1:30 and 2:30 to get that close look at the Big Eye, the Hale telescope.

CAVANAUGH: And what are the best conditions for you guys to observe space?

KARDEL: Well, when we have those nights when actually the marine layer blows in off the ocean and it comes in lower than Palomar, so we get this blanket that covers the city lights, we can get a significantly darker sky. So if we can arrange for that on a new moon, we have no interference from moonlight, less light from the cities, and if it’s a stable atmosphere as well, then we have a really pristine view.

CAVANAUGH: And how’s that working out for you?

KARDEL: Well, we’re not really into the whole weather modification thing and people probably wouldn’t like it if we made June gloom year round.

CAVANAUGH: Right, exactly. Kris, I wonder if you could tell us about the new projects that are coming up for research in the universe. What new telescopes are we seeing in the skies, and on Earth?

KOENIG: Well, there’s several really exciting projects going. Next month, on May 5th, there’s two European satellites or space telescopes going up, the Herschel and the Planck telescopes. Those two will start looking for early – one is going to be looking for things in the early universe and another one is going to be looking for planets. We also have the ALMA Project coming up online, and that’s the Large Atacama Millimeter Array (sic) that’s going down in Chile. It’ll be 68 sub-millimeter radio telescopes so it’ll be laid up on a plateau at 17,000 feet and will give us an opportunity to peer into regions of star formation that are obscured by clouds and dust and gas. And that’s going to be just a wonderful project that’s going to open up a lot of doors to us in our understanding of how stars and planets form. And then we get along into the middle of the next decade and we’ll have the giant Magellan telescope that’s part of the Carnegie Observatory so that’ll be built. We have a telescope that Gordon Moore has funded called the 30-meter telescope and that is a Cal Tech UC project and that should be built in Hawaii and that’ll be coming online. And then the big daddy of all telescopes, the Europeans are doing a telescope called the European Extremely Large Telescope…

CAVANAUGH: That’s a good name.

KOENIG: …more than 42 meters in diameter, so we’re talking about half the size of a football field. This thing is going to be enormous. And that telescope, along with some adaptive optics and some new detectors, will probably glimpse the formation of early star formation right after the Big Bang. And that will be the next really major leap in our understanding of cosmology and how the universe works.

CAVANAUGH: You know, in doing some research for our conversation, I picked up a little rivalry between the worlds of space telescopes and Earth observatories. Are – Do each of them have their strengths and weaknesses, Kris?

KOENIG: Absolutely. Absolutely. Up until the invention of what’s called the adaptive optic systems, which is our ability to remove the aberration that our atmosphere puts into starlight, so as starlight passes through our atmosphere, it gets refracted by temperature and winds and it makes the image twinkle. We all like the old nursery rhyme “Twinkle, Twinkle Little Star.” Well, that’s an actual physical effect by our atmosphere. So when we launch the Hubble Space Telescope and these other space telescopes, we get it out of that atmosphere. It does two things, it improves the image so we don’t have that problem and also opens up the door to wavelengths of light that cannot come through that atmosphere. And so space telescopes in the beginning was, well, this is the end-all, the be-all, we can get out of this atmosphere, we can see the universe all the way across the whole spectrum. But the problem is, is that we’re limited by the size of the telescope that we can send up into orbit. It will always be smaller than Earth-based telescopes and the whole goal of the telescope is to gather light. So the bigger the telescope, the bigger the mirror. The reason we went from the 100-inch and the 200-inch at Palomar and we’ve eventually gone into now the 8-meter class and 10-meter class telescopes was to gather light. And with adaptive optics and with our ability to basically theoretically build any size telescope now on Earth, we can gather more light and actually rival or surpass, in some cases, we have surpassed here on land the resolution of the Hubble Space Telescope. Now that doesn’t mean that one is better than the other. We actually – Astronomers actually use them as an orchestra when they’re doing their research. You have different instruments to give you a different view of the universe to provide more information in one way or another that the other can’t. So in the case of, let’s say, a super nova, an amateur in his backyard in San Diego may actually see a super nova in one of his favorite galaxies. He picks up the phone or gets on the internet, types in a message to the International Astronomical Union. That message basically gets out to the professional astronomers. The professional astronomers will then take the smaller survey telescopes even up in Palomar, they’ll turn it to that object, they’ll start studying it. Two days later, the Hubble Space Telescope is on it. They’re observing that light curve for ongoing research in many, many areas. And this is what’s happening now with astronomy. It is a collaborative effort between land-based and space-based and even the amateurs now are playing a bigger role than they did 10, 15 years ago because the technology’s come into their backyard. So the citizen scientist has been reborn in our country and the world, and it’s great. You know, there’s amateurs finding planets around other stars today. They’re involved in super nova searches. And so you don’t have to have a Hubble Space Telescope to do astronomical research. You can do it in your backyard. And it’s just a beautiful time. It’s a golden age of astronomy and it’s great to have this 400th anniversary built around it.

CAVANAUGH: And Palomar, Scott, has a five-year observing project. What can you tell us about that?

KARDEL: Well, we have a new project called Palomar Transient Factory so we use this wide angle telescope to do nightly surveys of the sky, and that data is beamed off of Palomar because we don’t have an internet access, basically off to the internet and then up to Berkeley where computers there will look at the new pictures that come in and compare them to old pictures and say, oh, this is different. This is interesting. Then beam the data back to our 60-inch telescope at Palomar. And all of this process so far is totally automated. There’s no person involved. The 60-inch telescope will then go look at these new things that are found. We call them transients, things that come and go or flared brightness like a super nova that Kris mentioned. And then it will perform this second set of observations to try to determine what this thing is. And if it’s sufficiently interesting, then you get a person in the process, maybe at the 200-inch at Palomar or maybe at Cal Tech, eventually the Hubble Space Telescope or around the world, and do a detailed follow-up. Usually that involves getting a spectrum so you can analyze the light to tell what it is, how far away it is, what’s going on. And we’re finding that this new survey, basically by taking people out of the equation and having this awesome computing power to go with it is allowing us to find things as never before.

CAVANAUGH: And that’s part of the collaboration process that Kris was telling us about.

KARDEL: Absolutely. And one of the things that’s really key now is, as Kris mentioned, we’re in this golden age so we have fantastic computers, we have not just visible light telescopes like Hubble and so forth but we have radio telescopes and telescopes that can see x-rays and see ultraviolet light and infared light. And these are different pieces of the equation, the puzzle, of what’s going on. And so we can examine things as never before.

CAVANAUGH: Well, I have to wrap it up there but I want to thank both my guests. Scott Kardel, public affairs coordinator for Palomar Observatory. Thanks for coming in.

KARDEL: Thanks for having me.

CAVANAUGH: And Kris Koenig, producer of “400 Years of the Telescope: A Journey of Science, Technology and Thought.” Thank you so much, Kris.

KOENIG: Thank you for having me.

CAVANAUGH: “400 Years of the Telescope: A Journey of Science, Technology and Thought” will air on KPBS TV, Monday, April 13th at 10:30 p.m.

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