Roger Angell, United Kingdom Schmidt Telescope, Angle Shirley Telescope discussed on Space Nuts
There are protections which are more or less effective depending on you the local circumstances just like to go back a little bit to talk about spectroscopy again and specifically ask you about your role well in developing multi object spectroscopy. I had never. I know what that is. Please explain an executive order it. Does this marvelous marvelous technique invented by William Huggins effectively the idea of using a spectroscopy for a spectrum graph which records the spectrum originally it was photographic now hold on electrically to workout. What's going on in the heavens? That became very much stock in trade astronomers during the first seventy years of the twentieth century. Words up until the nineteen eighties. It still is but the a big change happened in the early nineteen eighties. Because in the early days you had to meet your observations one star at the time. It was the only way a telescope under spectograph combination could work then in the late one thousand nine hundred seventy s a man with us absolutely delightful name Roger Angell who looked to the heavens German Brit. He works at the University of Arizona Eh. He's retired now. Still one of American astronomer astronomy very favorite strenuous Roger. Angell thought well outside outside the box in terms of how you could use technology to to you know improve astronomy and he got mixed up with fiber optics now fiber optics were until nineteen seventy. Were essentially an entertaining diversion. What what they are is stones of glass very fine strands of what we now use for fines and yes? That's right exactly. It's actually not quite a few silica which is classy. Material material drawn into these fines strands seldom more than a tenth of a millimeter diameter with the hair. It's it's yes that's about twice the width of very very fine. And they have the property that like put light in at one end and it will come out of the the other now they were known back in the nineteen fifties lava lamp lava lamp different ones. And the Yes. That's right all right. Yeah go sorry for my aside. There they were known back in the nineteen fifties these fiber optics but it was only in nineteen seventy that the corning glass works in the United States manage to draw fibers. Because that's how you make them start off with a block of glass and then you melt it and pull it out into these strengths. And they manage to draw fibers with extremely low losses by that. It means that if you put light in at one end most of it comes out the other disruption eruption. Well it's it's attenuation is. The technical is a reduction in the amount of light absorbed by the fiber before that you put light in at one into not tiny dribble came out of the but from nine hundred seventy with these what were called low loss optical fibers that's when they became a potential chill for the communications industry and so Calling it it allows sound and light to pass through it does allow any other it allows. There's light to pass through it. You Can put light in at one end and it will come out the other if you want to transmit sound through it. You've got to turn that sound signal into light clever modulating citing a light source you imprint. A sound wave on through and and that transmit through the fiber comes out the other end. You need decode and you get the sound route. So that's how communications work but astronomers and Roger Angell in particular. He thought well. These things are brilliant because astronomers are always jealously regarding the amount of light that they receive because it is so faint usually we're talking about single photons. Individual particles light so can can we use these newfangled optical fibers and in fact he's first idea was to have many many telescopes smallish telescopes all coupled together with optical fibers. So Oh you gather the light from all these telescopes and bring it back to a single place and you cannot do all the light together on one single object or one single object. That's right but then he turned the idea on its head and realized that with one big telescope which is looking at an area of sky instead of just taking one star or Galaxy Alexey from within that field of view you can actually use these optical fibers to line per fiber on many many objects simultaneously. So let me get this right. We have a field of sky. We have maybe a planet or is that too close. We don't bother with planets looking at enough galaxies and fire off stars and we could have fifteen or twenty items in sky and we could be looking at all of them and getting this barcode information from the stars Civil Tony's because you you can put a fiber on each one and in fact the first one I built actually had thirty nine optical fibers which by the standards of the day were quite quite large means thirty thirty nine objects simultaneously. So what what Roger Angell duty you got a PhD student. By the name of John Hill to work on this build something called Medusa which Medusa head thank you and that had think twenty-five fibers and they tried it out on a telescope in Arizona at the Steward Observatory and it worked. It was a technique that worked really well L. But then astronomers Australia got hold of the idea and in particular an engineer at the Angle Shirley Telescope by the name of Peter Gray. He worked out that you could engineer this thing. In a far more effective way the Medusa I worked with Peter. He was working with the anglo-australian telescope. I worked with a small telescope telescope called the United Kingdom Schmidt telescope which has a very wide field of view and together we produced a kind of workable optical tickle fiber systems for these two telescopes which kind of took the lead in the world on this science. Could you tell us the names of these. Well Peter Peterbilt you built the. What was it called fiber optic coupler psychot- remember the name but it turned into fo cap that was the acronym I built? Something called the fiber linked array imagery for matter which was flare then flare worse built in the early nineteen eighties. It was the first multi-fibre telescope spectroscopy system that coupled telescope to a spectrum graph which was actually stationary in the dome. Now that sounds weird an esoteric but what it meant was the spectrum of which is a very delicate piece of equipment was not riding around on the back of the telescope. It was fixed on the floor and was incredibly stable. And that's so we were the first to do that. So flair was the pioneer. Then I built a second version. Because flair had certain inadequacies the second one was the panoramic area coverage with higher efficiency. which was panache panache? A Well what clearly came next finesse. Until one of my colleagues said Venus stands for fails to interest nearly everyone saves spectrograph engineers engineers well. She called it flat to then evolved to a robotic system with more boring name of sixty F- with one one hundred fifty fibers that was commissioned in two thousand one and now a building an amazing machine called Taipan which uses things called starbucks so each optical fiber sixty had robot a single robot move the fibers around but with Taipan h fiber dopey. Three hundred in the end has its own micro robot round meanwhile anglo-australian telescope back in one thousand nine hundred ninety six built something called to death to the F. stands for two degree field. That's the amount of sky the thing sees in two F. Four hundred fibers but after tell you the aero which now stands for Australian astronomical optics used to be the Australian Astronomical Observatory. Hey always building. A system with more than four hundred fibers for telescope in Europe a European European telescope straight cuts way up doesn't it. It really does punch above its weight with regards to -nology develops right. That's why Australian astronomers Jonas have had such an given where small country because we have this equipment that we build it probably more effectively than anywhere else Somebody said we should call ourselves. Fibers are us. Because that's what we do. We do optical fibers the tech. The technique technique is in use around the world but many of the ones that are used elsewhere ones that have been built started struggling anticipate so just keeping bring on technology. Same here I heard Margaret Atwood before papal. She's the person that wrote. The Maidens Tail Modem Handmaiden handmaidens and. She comment was that old. Technologies have got good use a bad use and stupid. I use that we never considered and just thinking about lights and particularly with astronomy. What would you think the good the bad and the stupid well look for optical astronomy that's visible light astronomy not now talking about radio astronomers rexroad strong because these these are all different disciplines? Although we're all looking at the same things in a different way and often those results all piece together optical astronomers and and they're talking trades light so they are obsessed with light a more especially obsessed with with actually getting the very the best information from lies so the good is what we learn from from the from from the sky by Sifting light through the spectrum and other types of interest yep yep the baddies light pollution. So that's when light. which is it's been used for completely innocent purpose but gets out of hand in particularly in the light plumes of cities and and really goes back to the early twentieth century when councils putting lights with really no regard to what that was doing tonight sky because we simply simply never thought about it was becoming a problem by the time of the Second World War? It's really interesting. Is that in Los Angeles which is very next very very near the Mount Wilson Observatory in fact exceed Los Angeles from Mount Wilson. Where at the time? The biggest telescope in the world was during the second world. War centuries had had blackouts in order to to mitigate the possibility of invasion and during that time huge astronomical discoveries as were made because the the night sky koby seeing properly from moments again So it was inadvertent. So that's the bad side just on that I. I've attended some conferences in the U. K.. And one of the issues that they have when they talk about. Trying to mitigate light pollution the K.. Is that if you start talking to pay pooped in that sort of generation of about turning of streetlights and they feel like it's taking them back to that so I just like the blackout out to do that in blackout. Yes or no. I remember people saying that's true but it's not a blackout. I mean what we're talking about now is good lighting eh because this been huge progress in the last twenty years with understanding the ills of light pollution and not just for astronomers where the where the least least important in many ways of of the consequences of Bob Lighting. I again when I talk to groups about pollution. I often or haven't often and but I have been asked by people worldwide. Do we have to keep the lights down for the astronomers. When you've got a whole heaven stars you know? Why can't they study the start of the left or the brightest star or whatever and I think in some ways we lost that argument where we talked thirty years ago when when the International Dark Sky Association started and it was astronomers saying are we losing our night sky that that story was lost on the general public? I didn't understand the information that you're getting about heaven. That's probably true thing I'm most people think an astronomer is middle age bald man with a white coat. Who's got a long spindly telescope? And just spend his nights looking through uh-huh nothing could be further from the truth. It's all about you know. Well directed a scientific problems. We're trying to understand the universe because that understanding my actually actually turn out to be really useful to us one day and it's it's conducted in a very very progressive ways. Not just looking mistake. The sake of looking were studying and of course. The great thing is that it's no longer and more pulled middle aged man we we are. How far more diverse? So that's the good in a bed. Yeah stupid stupid. Use of technology that maybes. He's come through astronomy through light and and I know of things you talked about. Doppler effect isn't so I actually almost Lump the fiber optics work that I was talking about into their it certainly quirky. Because in you know I in one thousand nine hundred seventy. Nobody had thaw in this direction. It was Roger Angell towards the end of the nineteen seventies. We're thinking outside the box or this to what you could use these technologies for and I do remember number when I started working on this in one thousand..