 So Chris has been talking about the telescope itself and the science. John has been talking about the instrument that receives the light. And I'm going to be talking about something which is in between, which is called adaptive optics. And adaptive optics, as I will show you, is something, a kind of instrument that processes the light, cleans it, so that the instrument can actually take advantage of the full resolution, the optical resolution of the telescope. Australia, in the past years, we've been developing expertise in adaptive optics, and that's actually one of the areas where we think we can contribute in a major way to GMT, as I will show. So, what is adaptive optics for us and what does it do? Well, Chris told us that when you build larger telescopes, of course it's to answer a fundamental question about science, but how does it do that? Well, you'll be a larger telescope because it's going to collect more light. That's an obvious point. But something you have to know also is that when you build larger optics, the amount of detail that you can see in your object also grows, and it grows inversely, linearly, with the diameter of the telescope, meaning that if your telescope diameter increases by a factor of two, the amount of detail you're going to be able to see in the image is four times the amount of detail you are seeing with the initial telescope. So that's illustrated by this slide here, where this is here an image that you would see with the VLT, which is a ground-based telescope. This is an image that can be seen, actually, nowadays, by the HST, the Hubble Space Telescope, which has a diameter of 2.5 metres. Now, if you go to this eight-metre telescope underground and you apply it at the optics and you just forget that there is atmospheric turbulence, then you can see many more details. You can see deeper, you can see that the exposure now is going down from 1,600 seconds to 166 seconds, but you can see also more details. If you go to this extremely large telescope, and that's what it will provide, it will provide many, many more details. And it's the same as saying that your angular resolution is actually increasing quite significantly. And on top of that, of course, because you have a larger collecting area, your exposure time decreases quite significantly. Let me demonstrate the power of having larger and larger telescopes. However, what's bad when you have a ground-based telescope, meaning a telescope which is built at sea level or on the ground, I mean, not in space, is that you are going through the light coming from an astronomical object is going through the atmosphere. And the atmosphere is bad for astronomical imaging because what the atmosphere does essentially, if you look at this star here with a large telescope and you blow it up, you know, many, many times you are kind of zooming on this star, what you see is that. And that's the effect of atmospheric turbulence. So it's the same as if, you know, in summer, you are looking at a distant object across a desert or across a parking lot, you will see it moving. The image is moving. Well, it's exactly the same when you are looking at stars. And so in effect, what it does is that the image that you had before with this atmospheric turbulence is now transformed into that, which is a blurry image. And in fact, the fact is atmospheric turbulence blurred the image, so taken from the ground. And it does so that the angular resolution of a 25 meter, for instance, the GMT, is actually not better than the resolution that you would get with a 20 centimeter telescope. So of course you have many more photons, but if you don't do anything about it, you don't have a better angular resolution, which means that you won't see more details. So to solve that situation, you can do two things. You can go in space where you don't have any turbulence, you don't have any atmosphere, but it costs a lot of money. I mean, typically, you know, space missions, they are extremely good, but they cost about 100 times more than an equivalent telescope on the ground. Or you can try to correct for this atmospheric turbulence that has induced this blurring of the images. So that's what I'm saying here. I'm going to demonstrate you how we do it, but adaptive optics can fix this and restore the ultimate resolution of your telescopes. Okay, so how does it do it? Well, essentially it does it with two main optical elements. Two main elements, I would say. One is what we call a waveform sensor, which is in fact, you could call it a light wave sensor. So what it does is that it looks at the star and analyzes the deformation of the light wave being induced by the atmospheric turbulence. And then this information is processed by a computer and sent to deform a deformable mirror that wobbles and counteracts, in fact, the effect of the atmospheric turbulence, so that when the light, you know, the distorted light bounces off this deformable mirror, it's straight again, and therefore allows you to reach the ultimate resolution of your telescope. So that's a technique that's been around for about 25 to 30 years, first developed by the military in the U.S. and then applied to astronomy about 22 years ago, and recently it's been also applied to medical imaging and other type of science applications. All right, so it exists. It's been around, as I said, for 22 years. It's installed in most of the 8-meters, or even all of the 8-meters telescope in the world, but a couple. And that's actually, you know, a real result that you can, that they have gotten in, for instance, the Gemini 8-meters telescope. So this is what you get looking at this globular cluster where you don't use adaptive optics, and if you use adaptive optics, that's what you get. So it demonstrates very, very clearly that with adaptive optics, you see first more details, many more details, but you can see also deeper, because, okay, here you see all of these deep, very faint stars, you don't see them whereas it reveals the faint stars here with adaptive optics. Another very nice example is, for instance, by a Keiko observatory that Chris was mentioning earlier. This is a new major of Uranus, without and with adaptive optics. So you see the really striking difference. So one thing which I'd like to show, because it's very nice, is that it's related to laser gas stars, and I'm sure that if you have read about adaptive optics, you have heard about laser. It's something that you might see within the next couple of years atop Stromlo because we are developing also a system with laser guide stars for different applications. But it's something which is related to the need of a reference source. As I was saying, you have a lightweight sensor. So if you have a sensor, you have to have a signal. And the signal is provided by a nearby guide star, or a star, just a star. But sometimes you're looking at a fraction of the sky in a direction where there is no bright star. And then, well, before laser guide star, you couldn't do anything, you just go to somewhere else. Well, now there is what we call laser guide star, is that if you don't have a star, you can create your own star to be your reference signal. And you do that by actually shining a laser, which is at the sodium wavelength, it's the same orange wavelength that we have in public lights. And you actually excite sodium atoms that are 90 kilometers above ground, and they fluoresce, they shine, and you can see you can collect some of the light. And it serves as a guide star. So it's extremely nice when you go now in many, many sites, you can see guide stars. This is a picture, a long, long exposure picture taken at Gemini, and I have also a movie which shows, that's actually, it's been taken at Monakia, in Hawaii. One of the Gemini telescope is there, to which Australia has a partnership. And you can see that, for instance, those are the two tech, they are pointing toward the galactic center over there, and they were using laser guide star. Another big success actually was the discovery of the black hole and the, oops, okay. So it's actually quite impressive, because at the top of Monakia, there's four telescopes having laser, and sometimes you see the four lasers shine during the same night. So it's quite impressive. The bad thing about laser is that other people know where you are pointing, so you cannot hide it anymore. All right, so this image is dear to my heart because it's an instrument, first of its kind, a West PI for that, at Gemini. Actually, AO Adaptive Optics was the first concept, but now it has diversified into different breeds. So you have the Adaptive Optics, for instance, for moderate resolution gain, but very wide field. You have other Adaptive Optics to study planets that are very, very small field, but you go toward very, very high image quality. That's an example. It's actually one of the most, I think, exciting applications of Adaptive Optics because now, for instance, this is the ground dwarf GL-299 as it was discovered by Palomar, then imaged by HST, and this is now what you can do from the ground with eight-meter telescopes. You see how far, how superior this is compared to even space just because of the nice control of the light and how it scatters it. And finally, so as I said, there is a strong expertise in Adaptive Optics in Australia. There is three instruments, plus a laser-guest star facility that are envisaged for GMT. And I hope that we will play a major role in two of these, the laser-automography Adaptive Optics and laser-guest star facility. And finally, okay, so that's a simulation. This one is not a real image of what we should achieve with the GMT with Adaptive Optics. Without, sorry, and with Adaptive Optics. And finally, my last view graph is to say that aside this GMT activity, we are also applying this knowledge to other things. Like, for instance, we are a participant at the ANU to the Cooperative Research Center for Space and Environment Management, where we are applying Adaptive Optics techniques to track and eventually maybe deal with some of the space debris. So that's a very interesting application. Thank you.