Let's talk about the big glass that astronomers are building for our next generation of telescopes. The LSST mirror is sturdy enough that you can sit on it. As you can see in this picture, also it's huge. It's the size of your living room or larger. Not just telescopes on the ground but telescopes in space are attaining new heights. The frontier for space astronomy will be the James Webb Space Telescope, the successor to Hubble. Time and cost overruns mean that the Hubble will die before the James Webb Space Telescope is likely to be launched. But James Webb will eclipse Hubble in its size. Being 6.5 meters in diameter. James Webb is an extremely challenging design. The mirror will essentially unfold once it reaches its location, a million miles from the earth. This is so far from the earth it is unserviceable by astronauts. This telescope has to work perfectly and correctly because it can't be fixed if anything goes wrong. That's very high stakes for a space mission. The mirror unfolds when it's situated at its proper location and the instruments deploy. There's a sunshade and solar panels as usual to get power from the sun. The individual mirrors are hexagonal elements. All of these have been fabricated and reach their specification. James Webb's instruments have been tested on the ground and in a vacuum, in labs on the ground and all have met their performance specs. The James Webb Space Telescope is almost ready to fly. James will vaults space astronomy into a new regime. The Hubble Space Telescope is 2.4 meters in diameter, about as far as your arm span will reach in neither direction. The Spitzer Space Telescope. A wonderful infrared facility is even smaller. Less than a meter across. James Webb vaults above these two facilities with 10 times more collecting area and it will indeed see to the dawn of time. In part because light from the distant universe is red shifted or shifted by cosmic expansion to longer wavelengths. The James Webb Telescope concentrates on a different spectral region than the Hubble Space Telescope. Hubble works in the ultraviolet, throughout the visible range and into the near infrared. James Webb will now work in the ultraviolet and and will only work at the reddest of optical wavelengths. Most of its work will be at invisibly long wavelengths just beyond where the eye can see. The degree of technical challenge of the James Webb mission is extraordinary. Because of the complexity and number of moving parts of the instrument and the telescope assembly, and the fact that it must be deployed robotically and remotely. Far from the possibility of servicing or fixing by astronauts. The engineers involved in this undoubtedly have had sleepless nights worrying about whether they're part of the complex mechanism will work as advertised when launch comes. We could hear from a NASA administrator or chief scientist about the James Webb Space Telescope. But I think it comes better from a young person. Anyone excited about the possibilities of space astronomy will recognize the James Webb is an extraordinary mission. Here at the top five reasons why the James Webb Space Telescope, freaking kicks ass. It is huge. The total mirror size is 7.5 times larger than the Hubble Space Telescope's meter. The heat shield is the size of a tennis court. Number four, it's a freaking transformer. So in order to fit into the rocket at super-duper folded up and then when it arrives it unfolds, in like 12,000 different marvelous little ways. That could go wrong at any moment and it freaks me out because I worry about that. Number three, it will operate 1 million miles from Earth. That's about four times as far away from the earth as the moon is. The Webb Telescope actually orbits the Sun. That's the simplification that's actually in the relative stationary Sun-Earth Lagrange 0.2, which I'm not going to try to explain to you right now. If it screws up there's no way to fix it. One chance to do it right or it's a $6 billion piece of space junk. That is tense. Number two, it will be able to see planets orbiting stars in our galaxy. Individual planets. If the James Webb Space Telescope was twenty-five light years away, it could see the Earth. It can also determine the chemical composition of planets and it can peer into stellar nurseries to see planets as they form. Finally, the James Webb Space Telescope can see 13.4 billion years into the past. We will be seeing the first galaxies as they form. The first stars as they form and guess what none of this is necessary to life on Earth. None of it's going to help us cure malaria or install a democracy in Egypt. But it is awesome in the truest sense of the word awesome. I'm sorry that there's somebody and gestures in this video I am feeling very gesturey. This is the dawn of everything that we know and that is increasing awesome. That is something that I can get behind. The James Webb Space Telescope will cover all of astronomy, working on topics from planets to cosmology. But it will may have a particular impact on two fields. One is the study of distant galaxies. Perhaps the primary focus of James Webb is going to be detecting first light in the universe. This is a time somewhat over 13 billion years ago, when the very first stars and galaxies lit up in the universe, which was cooling from a thin diffuse and almost uniform gas. This is impossible to observe with Hubble Space Telescope. It's simply doesn't have enough light-gathering power and it works primarily in the visible range not in the near infrared. James Webb will also do work on characterizing exoplanets. Exoplanets had not even been discovered when the James Webb was first conceived of. So this is new science for that telescope. But it will be able to do spectra of exoplanets to try and look for bio markers. That is the chemical signatures of life on a distant planet. A very exciting project. It is nonetheless extremely challenging even for this large telescope. James Webb is long overdue and over budget and the price tag has caused some stress to the astronomical community as well as to NASA, which manages this large project. But James Webb has an almost firm launch state somewhere around the end of 2016 or early 2017. It's passed all of it's technical hurdles and astronomers are starting to anticipate it with pleasure. That's big glass in space. What about on the ground? We've seen some of the examples of big telescopes that are being prepared at the University of Arizona using our mirrors. The largest single dish at the moment is actually a non-steerable optical telescope called, the Grand Canary Telescope built by the Spanish in partnership with other organizations. It's on the Canary Islands, where there's a major observatory and this mirror can only stare at one strip of sky that passes overhead. That allows the mirror and the telescope to be quite cheap. Because no large structure is needed to steer around the sky. The next very large telescope to be commissioned we hope will be the Giant Magellan Telescope. A partnership between the University of Arizona and the Smithsonian Organization and a set of private and public universities in the United States. This telescope should be commissioned sometime late this decade. It's going to be built on Las Campanas Observatory side, where we already have a pair of 6.5 meter telescopes. This visualization of the structure shows the size and complexity and also the ability to grasp light from across the universe of this wonderful facility. Even larger than the GMT, then a friendly competition with it is the 30 meter telescope, which is being built by the Caltech and University of California Consortium. There's a friendly rivalry here. In fact the world perhaps could do with a couple of these large telescopes since there's plenty of science to fuel more than one super-large telescope. The TMT will almost certainly built either in Hawaii or also in Chile. It's a 30 meter telescope, so is larger than the one that we plan. It will use the Mosaic Technology. Essentially scaling up the cake concept rather than having single large monolithic mirrors. An animation of the very center of our galaxy shows the importance of having these super-large mirrors. With their diffraction limits realized by the use of adaptive optics. If we look at the seeing of standard monicea site, which is exceptionally good. There's just a blur where the star cluster exists at Sagittarius a star. This is the dynamical center of the galaxy. What astronomers want to do is track individual stellar motions over a period of years. The motions in the animation to deduce the mass of the central black hole. Separating out the motions of the stars implies resolving those stars and when they're a blurry mess, as seen without adaptive optics that's impossible. The first step in this progression, is the use of adaptive optics on the keg 10 meter telescope. This goes some way towards resolving a few dozen stars in the galactic centers whose motions can be tracked with time. But to go beyond that with a 30 meter telescope and adaptive optics, increases the number of probes of the black hole at the galactic center from a few dozen to perhaps hundreds and these motions can be studied in exquisite detail. When telescopes get very large, astronomers essentially run out of things to call them. The names almost get silly. There's a telescope that originally was called the Overwhelmingly Large Telescope OWL and has been renamed the Extremely Large Telescope which is a project of the European Southern Observatory. A consortium of countries based in Europe who's observatory is in Chile in the dark skies and high site just south of Las Campanas Observatory, where our telescopes are located. This project was supposed to be a 100 meter diameter mirror. If ever built at this size it would rival the largest human objects made the Great Pyramid at Giza or any of the big cathedrals of classic Europe. An enormous structure. Imagine a mirror the size of a football pitch pointing with a precision of one part in 10 to the seven, to any part of the sky in just 10 seconds a phenomenal undertaking. The reason to do this is the same as the reason to build any large telescope. When coupled with adaptive optics, the 100 meter aperture gives you even better angular resolution turning a blurred mass of a star cluster into the pinpoint of hundreds or even thousands of individual stars. This exquisite imaging lets you answer scientific questions that could not possibly be answered either without adaptive optics or without a mirror of this size. In the last few years, budget realities of setting in Europe as in the United States and the 100 meter telescope has been de-scoped to a mere 42 meters. However the project is not yet fully funded. When built it would indeed be the largest telescope in the world. Astronomers hunger for photons to reach even deeper and further into the universe is unquenched. The biggest glass being contemplated in space is the James Webb Space Telescope, which will be a worthy successor to the Hubble Space Telescope when it's decommissioned in a few years. Six and a half meters in diameter, it will search for first light in the universe. Meanwhile on the ground, telescopes 10, 20, 30 and even 40 meters are planned. Ground-based observatories that we'll each cost well over a billion dollars and will give unprecedented depth and scope when coupled with the technique of adaptive optics.
