I wanted to tell you something about, not the work that I did to gain the Nobel Prize but what's happening now and coming.
I wanted to say that growing up as a child I thought the most exciting thing I could do as a scientist was to build equipment that would measure things.
So rather than trying to observe them, which was difficult, let me build something.
So, that's what I've been doing for my entire life is figuring out how to build stuff to measure things.
So I want to show you what is currently ongoing for us in astronomy and not just my particular work but other people's work.
Just to give you some sense of what's coming.
So I have a crystal ball for you.
If you visit this particular website it till tell you everything.
But I'm not going to go visit because I don't have a good question.
So, we have an amazing tool now that we didn't have 30 years ago which is we have a super computer.
We can take a computer and imagine that what Brian just said is correct.
That the universe is full of cold dark matter and dark energy causing the acceleration.
And ordinary matter.
And we can predict from super computer simulations with 10 billion particles in a box, what the gravitational forces will do.
And here is the simulation, the formation of a galaxy.
This is a small sample of 10 billion particles.
And you can see this happening before your very eyes in the computer.
So this is one of the most powerful tools that we now have.
But we have to admit that we don't know if it's true.
So we are going to have to go measure something to find out if that beautiful picture that I just showed you has any resemblance to reality.
So far it seems to match but of course it's telling us about things that happened over the course of 100's of millions of years, even billions of years in the early universe.
And how are we going to tell?
We are like, if you go to the football match and you take a picture of the entire crowd of people there.
That's like taking a picture of all the galaxies that exist.
And you see small people, large people, young people, old people and now you the scientist had to figure out how do small people become large people.
And what is the history of people from taking a picture of the stadium full of football fans.
So we have the same problem in astronomy so we're going to have to figure out
how to compare the movie that I just showed you which is dynamic in time with what really happened.
So another thing I wanted to mention is that this is going to happen to us.
Here is another super computer simulation of 2 galaxies colliding.
We know that the Andromeda Nebula which is the nearest large galaxy to ours is headed in our direction
and we expect a collision to occur roughly like this in about 2 or 3 billion years.
So it will be probably not observable to us because the sun will also be getting brighter over that period of time
and it will be too hot for us to live here on earth regardless of what we do about climate change and energy sources.
Another thing to point out about this one is that the solar system is on the outer boundary of our galaxy
and it is pretty likely that it will be expelled from the galaxy altogether and it will go flying off into space in between galaxies.
But in the end what we see in this picture is that the 2 galaxies merge and form a beautiful spinning object.
By the way, if there's a black hole in the middle of each galaxy as seems to be true there will also be now 2 black holes in the middle of the combined galaxy.
And eventually the 2 black holes will merge together.
Then according to calculation they will produce a burst of gravitational waves coming out.
Gravitational waves have never been observed in nature directly.
Although we have deduced that they exist and a Nobel Prize was given for that proof.
Anyways.
So this is likely to happen to us.
And now how are we going to know if any of this is true.
So another thing that astronomers really want to know and probably you want to know also, how did we get here?
So how about planet formation?
Now since about 1996 or so we've been aware that this process occurs.
That there are many planets around other stars, once in a while a planet will pass between us and a more distant star and will block some of the star light.
So we can now observe this.
In space especially it's relatively easy to do because we have very stable telescopes in space, no fluctuations from the earth's atmosphere.
So a little bit of the star light passes through the planetary atmosphere on its way to our telescope.
We can now analyse that light and determine the chemical composition and the physical properties of the atmosphere of a planet around another star.
To this has already been accomplished with a fair number of such targets.
We have a catalogue now from the Kepler observatory, which has been flying for a couple of years now, I think, of 2,000 such planets.
And there are a few that somewhat resemble the earth.
So we are getting close to understanding whether planets like the earth are common.
And we can say that they're not very common but there are many, many planets.
There are more planets in the galaxy than there are stars.
Very, very common.
So now however let me talk about how do we learn about these things.
So I want to show you the beginnings of telescopes.
I'm going to illustrate some of the great projects currently underway to learn about the rest of the universe.
So I'm going to present them roughly in the order of increasing frequency of the photons that we use.
So at very, very long wavelengths we cannot see anything from the ground
because the earth's ionosphere is opaque and it reflects all the radiation back down to the earth that we transmit.
And conversely it reflects all the radiation coming to us from outside away.
So on the other hand, it is possible in certain parts of the world to go to a very quiet place and build this collection of dipole antennas
which are hooked together electronically to synthesise a map of the sky.
So this is a proof of concept observatory.
Various things that we are aiming for with this radio telescope.
Among other things, we hope to see the beginnings of the first emissions from hydrogen lines.
Now hydrogen emits here on the ground at a frequency of 1,421 megahertz.
If you are observing hydrogen at a great, great distance away, the material that's going away from us because of the red shift, the wave lengths will be much longer.
And so we use these very large rays of dipoles.
They're all hooked together by cables and actually produce an image of the sky by Fourier transformation of the waves that come in.
So this is a case where computer technology has enabled us to do something that was never possible at all remotely before.
So, another thing we're working on now is something called the Square Kilometre Array.
Can you imagine a telescope covering an entire square kilometre?
Well there are 2 concepts and the international body that decided which one to choose has just decided to do both of them.
One will be built in Australia where it's relatively quiet, it's very far away from cell phones and other radio transmitters.
The other one in South Africa, likewise a place that's protected from radio interference.
So these are coming and it's a very difficult and expensive project but it is coming.
The technical design has been basically completed.
So we know what to build.
So this will be able to detect things that we have barely only imagined.
And of course we hope for surprises.
You can just see from the picture how truly immense this is.
We have already...
We're nearing completion of this beautiful observatory.
This is called the Atacama Large Millimetre Array.
This is a collection of about 64 radio dishes in the high desert in Chile.
It's a high enough altitude that people that go there require oxygen to be safe.
There are little buildings that they have for you with enriched oxygen atmosphere.
This is another totally amazing technological miracle.
To make this one work we have to have microwave receivers at the focus points of each of these dishes.
They have to be connected by fibre optics.
And we have to measure the relative phase of the waves that are coming in to the different telescopes with a precision of a small fraction of a millimetre.
In order to again use the giant computer to create an image of the sky.
The computers that it takes to do this processing use hundreds of kilowatts of electrical power.
And they are probably the most powerful special purpose computers anywhere in the world.
Because they're not general purpose they can be optimised.
But at any rate, we're already able to create images with the first dishes that have come on line.
And there's one on the upper right corner.
Comparing the radio picture with the pictures that we get at shorter wavelengths with the Hubble Space Telescope.
So, the radio picture is quite different from what we see with the Hubble.
And they've shown the different wavelengths in different colours.
So now I want to talk just briefly about the equipment that we use to measure the cosmic microwave background radiation and what is coming next.
Back in 1974 I was a recent escapee from Berkley, California.
I had finished by PhD, working on a thesis project to measure the cosmic microwave background radiation.
And I had concluded that this subject was extremely difficult because my thesis project actually failed to function correctly.
It was a balloon instrumentation that went up on a balloon, it did not work at all for 3 different reasons.
We got it back and my lap partner put it in a test chamber.
We found out why it didn't work and then they flew it again later and it worked the second time.
So it was now possible with that apparatus to measure the spectrum of the cosmic microwave background radiation, how bright is it at each different wavelength.
Now the Big Bang theory tells you that the spectrum of this radiation must be perfectly black body.
And so that apparatus, the balloon burn apparatus, said yes it's pretty close but not exactly.
But then certainly after I left Berkley NASA said we want proposals for satellite missions.
This is now only 5 years after the Apollo moon landing.
So what is NASA going to do?
So propose satellites.
So, I said to my postdoctoral advisor:
"Well, my thesis project failed but it should have been done in outer space."
So we'd draw this little sketch and we built something about, like that upper left hand picture.
And 15 years later it went into space and I guess 17 years after that we got a call from Stockholm.
Because we had measured the Big Bang spectrum and it was indeed virtually perfect spectrum.
And as George will probably tell you more later, we also measured the map of the radiation.
And we found out it has hot and cold spots.
Which are the primordial structures that Brian was telling you about.
There are now more scientific papers written about those hot and cold spots than there are spots on that original map.
It has become a huge industry.
So following that everyone could see that we needed to know more.
So the middle picture here is the Wilkinson Microwave Anisotropy Probe.
It made an all sky map again but much better sensitivity and much better angular resolution.
And it is now the sort of strongest basis for what Brian calls the standard model of cosmology.
I would say that we may call it the standard model but it's extremely mysterious even if it is standard.
As Brian mentioned we have both cold and dark matter and dark energy.
Neither of which has ever been seen in a lab.
So, the third project on the lower right hand side here is called the Planck mission, it's a European mission with a small American participation.
And their cosmological results have not yet been announced but they are expected next spring.
And so we're eagerly looking forward to seeing whether there is a big surprise coming from them.
What is going to be done after this?
We are now hot on the trail of measuring the effects of the primordial gravitational waves, if they exist.
The hypothesis is this primordial material of the inflationary period with its quantum mechanical fluctuations had kind of equal partition
between many different kinds of variations and oscillations including gravitational waves.
There should have been some.
So what would their effect be?
We now propagate that idea forward.
We calculate that the cosmic microwave background radiation should have tiny, tiny polarisation patterns.
And these polarisation patterns should be detectable.
They're not that far out of reach today.
There is a possibility that they will be detected from the ground or with a balloon payload some time.
But if that is not done or if we need to do it better we have already ideas about how to do it in outer space.
So here is a concept from Goddard Space Flight Center where I work that shows a sort of improved version of the Cosmic Background Explorer satellite
but with polarimeters inside to make a map.
So it is possible that in another decade or so, maybe even less,
you will hear about the demonstration that either the Big Bang material had gravitational waves in it or not.
And this will tell us about the scalar fields or inflationary fields that may have existed that propelled the original expansion.
So, this is nature's particle accelerator for us.
It's capable of reaching much higher energies than we can ever imagine producing here on the ground.
So, a few other things to illustrate.
We have an observatory in space currently, built by the European Space Agency and its partners through Europe.
This is called the Herschel Observatory and they have already produced some very interesting maps.
This is the beautiful Andromeda Nebula.
The same one that is headed in our direction.
That is going to cause that beautiful collision.
It looks quite different with the infrared radiation that they measure.
You see these big rings out here.
These are rings of places where stars are being formed recently and they're very hot and they produce a lot of dust around them.
The dust absorbs the starlight and produces infrared radiation.
So a very different phenomena.
Here is a small American observatory in space measuring infrared radiation as well.
The telescope is 8/10 of a metre in aperture.
But nevertheless is able to see galaxies at a red shift of 2 or 3.
It's quite astonishing that such a small piece of apparatus can see so far across the universe.
But it is a demonstration that we were surprised one more time.
When people first proposed building a small telescope like this they said: "Oh, we won't see anything".
A few words about the telescope I'm currently working on.
This is called the James Webb Space Telescope.
By the way James Webb was the man who went to President Kennedy and said: "I know how to get us to the moon".
And by the way he also asked for enough money and so they got there.
And it took them less than 10 years, we can't even decide to try a project in 10 years.
So I'm reporting on this on behalf of all of current earth inhabitants, about 10,000 future users of the observatory,
about 1,000 engineers and technicians who are building it and about 100 scientists worldwide who are working on it and 3 space agencies.
Because this is a project partnership between NASA and European and Canadian space agencies.
So this is what this one looks like, this is the telescope in the upper right hand corner.
It does not look like your telescopes you have seen before.
It's nothing like Galileo's little tube of wood and nothing like the Hubble Telescope which is also like a tube.
This one is very far away from earth.
And we put it way away so that the telescope will be cold.
The sun and the earth are down here below, here is this big umbrella, here is the telescope, it's in the dark.
And it will cool itself down to 45 degrees Kelvin.
So by the way to name some of the people who are working on it, our prime contractor is Northrop Grumman which is a large aerospace firm,
primarily located near Los Angeles Airport.
Anyway we have instruments coming from around the world.
The University of Arizona.
The European Space Agency with their company Astrium.
Notice that we met one of the representatives of that company, who was here yesterday.
Jet Propulsion Lab and a European consortium producing another instrument.
And finally the Canadians are producing an instrument.
The telescope will be operated like the Hubble Space Telescope from Baltimore at the Space Telescope Science Institute.
So if you're an astronomer and you want to make a proposal you will be writing proposals the same way that they do today.
So, I think it will be ready in time for many of you to write your proposals.
So the telescope is huge, it is cold.
By the way the European Space Agency is buying the rocket for us.
It's an Ariane 5 rocket.
So we'll be launching the telescope from Kourou in French Guiana in 2018.
So a few things that we hope that this will see.
Well, this illustrates the improvement in sensitivity and angular resolution compared with the Hubble Telescope.
This is a visualisation from the computer of what the early universe might have looked like.
We will certainly hope to see the details looking down inside with the James Webb Telescope.
When and how did the galaxies form, how come they have the different shapes that they have.
How did the heavy elements of the universe get formed, we know for instance that since, as Brian showed you, we have only the lightest elements came from the big bang.
We're not made out of, primarily hydrogen and helium, we're made out of other chemical elements.
So they were all produced in stars that exploded and came back out again.
So we're quite recycled.
The infrared capability will enable us to look inside these beautiful clouds where stars are being born today.
The dust that's there in space is opaque.
And you cannot see through it.
So the aim of an infrared telescope is to see through the dust and around the dust grains.
So, here's an illustration of 2 pictures taken with the Hubble Space Telescope of the same volume of space.
The Hubble Telescope has some infrared capability.
And you can see this region looks totally different.
Visible wavelengths and infrared.
The visible wavelengths show these beautiful glowing clouds.
The dust is much more transparent, you can actually see inside the cloud and see that this star, whatever it is in there, is producing jets of material.
And it's probably a very young star doing that.
So another picture of the difference between infrared.
Here's one picture and there's the same volume of space again.
Here's the star in the middle sending out jets of material, quite different from what you see in the visible.
So this is a way of us to look inside the clouds of gas and dust where stars are formed.
And we begin to learn how this works.
So when I went to college people knew how this worked.
We still don't know how it works.
Because when we actually try to get the computer to simulate what we think is true, we encounter places where it just doesn't work out.
So how does the telescope work?
Here's a picture of the deployed observatory.
There are 5 layers of this giant sun shield.
By the way the sun shied is as big as a tennis court.
So where Serena Williams is playing that's how big this is, from there to there.
And of course we've never had a tennis court in space before so this is a wonderful engineering project.
The telescope is folded up for launch.
It's much larger than the rocket is.
So it's a tremendously difficult engineering project for that as well.
We will be putting it far from earth.
Here is the picture of where it is.
The moon at 384,000 kilometres from earth.
The Lagrange point L2, about 1.5 million kilometres.
So here is a movie showing how the telescope will unfold in outer space.
First we unfold the solar panels.
Then we unfold the little parabolic antenna that sends the data back and forth.
Now we begin to unfold the sun shield, the big umbrella that protects the observatory from the sun.
The actual deployment will happen a few days after launch.
We're not in a hurry, it doesn't run this fast.
Here the telescope is separating from the warm boxes of the spacecraft electronics.
Now we're unfolding the protective covers over the shield.
You might say looking at this: "Isn't this remarkably complicated?"
Answer is yes.
On the other hand, I asked our company: "Well, is this the most complicated thing you ever put into space?"
and they said no.
So they work for other government agencies as well.
So they have learned how to do big complicated things in space.
But I've never seen the other things that they do.
So here the telescope is finally coming to approximately the right shape.
The parabolic, it's almost a parabolic mirror.
By the way the telescope is clearly not in focus when it is launched.
All of those big beryllium hexagons that make up the primary mirror are adjustable in position and in curvature.
So that after a little while we will be able to focus the telescope and get a sharp image.
So, how are we going to test this on the ground?
Well, we have a giant test chamber at Johnson Space Flight Center in Texas.
And this turns out to be the same test chamber where the Apollo astronauts rehearsed getting out of the Apollo capsule onto the surface of the moon.
So it's very big and very capable.
We've had to improve it by putting cryogenic cooling shrouds around it so it has now not only liquid nitrogen to cool the interior but also a gaseous helium refrigerator.
So it will be capable of getting the telescope down to the temperature that it will have in outer space.
So we'll be able to verify on the ground that it focuses.
So if you want to know more there are many, many documents online.
If you just hunt for the James Webb Space Telescope you'll find our home web page and there are documents you can download and many scientific white papers.
So for much more detail it is available online, of course.
Just to...
I want to close with some other suggestions about what is possible in the future and what is happening on the ground.
The European Southern Observatory built this amazing collection of 4 giant telescopes on the ground in Chile.
Each one of them is 8 metres in diameter.
We took our James Webb Telescope team down to visit.
To see what was it like to get a huge telescope and of course we decided that we couldn't quite put an 8 metre telescope in space.
Ours is only 6 ½ metres.
But this collection has been working beautifully for a long time.
And some of the most interesting scientific results that you know of today came from these telescopes.
Here is one that is being built.
It's called the large synoptic survey telescope.
This is another 8 metre telescope with a very enormous field of view.
9.6 square degrees of field which means billions of pixels of CCD detectors.
So they will be able to scan the entire sky that they can see from their place on earth, every 3 nights.
So we will be able to find with this telescope things that change from night to night.
We will be able to find asteroids that move.
We will find supernovae in great numbers.
And possibly a few other remarkable things that change.
Gamma ray bursts may turn up for instance.
So anyway it's coming along.
This is something even more ambitious.
This is called the European Extremely Large Telescope.
This is a concept for a 40 metre diameter telescope.
40 metres, I guess it's about from here to the back of the room, right?
It's huge.
It is now logically possible to do this.
We cannot make a 40 metre piece of glass.
So, of course, as we do with the James Webb Telescope we will make the mirror out of many smaller pieces.
And we will adjust them to shape after the thing is focused.
So as I understood it quite recently the project has been approved by the European Southern Observatory subject
to continuing negotiations with international partners to get enough money.
But it is coming along and I fully expect that this one will happen.
In the United States we have 2 competing versions.
One is called the Giant Magellan Telescope.
This one has 7, 8 metre pieces of glass.
All figured to work together.
Again these have to be adjusted so they simulate the one giant parabolic mirror.
Some of the mirrors have already been made for this one.
And so this one I think was also going to come along.
In the United States we do not have much government funding for these, so private money has been raised.
And so assuming that that continues successfully we will either have 1 or 2 large 30 metre class telescopes in the United States.
Here is one that the European Space Agency has now approved to start development.
This is called the Euclid mission.
This is one which is going to test further the discovery that Brian described about the accelerating universe.
We would like, and this is top priority for both Europe and the United States, to continue to measure better the acceleration process.
We know pretty well what the acceleration is nearby.
We would like to know the history of the acceleration.
Now as you go farther back in time the acceleration is smaller relative to the expansion rate that already occurs.
So, it's only in the last 5 billion years that acceleration has been dominant.
Nevertheless we would like to know the entire history of the acceleration because then we would be able to say whether that W,
that parameter that he showed in his equations is actually a constant.
No one can prove that it's a constant.
We are right now assuming that it's a constant.
So this is a small telescope that would be able to cover a very large part of the sky.
And with tremendous sensitivity and able to basically measure the curvature of space time over here as the drawing shows.
I can't show you space telescopes without showing you the Hubble Space Telescope.
The Hubble has been visited 5 times by the space shuttle.
And astronomers have upgraded it.
It is still working beautifully.
It is working better than it has ever worked in the past.
So we don't know how long it will last but it's probably at least 5 or 10, maybe 15 years more that it will continue to work well.
What happens after that, NASA has to be responsible for it.
If we just wait for a while it will fall back down to the earth had could hit someone.
So we are required by international treaty to dispose of it safely, either we will have to boost it to a much higher orbit or we will have to aim it at the Pacific Ocean.
The piece of glass, there's several tons of glass there and it would come right through the atmosphere as a single piece.
So whatever it hits will be damaged.
Anyway right now we must send a robot to do this work.
We do not have plans to send an astronaut back to end the life of the Hubble Space Telescope.
Right now we're working on making sure that it continues.
You may have heard that the spy satellites have been given to NASA quite recently.
The National Reconnaissance Office is the spy satellite agency in the United States.
They built 2 telescopes which they didn't quite finish, they ran out of money.
But they said, eventually an agreement was reached with NASA.
So NASA will receive the parts for these 2 telescopes.
And now we're thinking about what to do with them.
If we can get funding to do it, we'll eventually be able to fly 1 or 2 telescopes.
These are as large as the Hubble telescope but right now there is no instrumentation to go with them, no space craft to carry them.
So, right now it's just the optical parts and some mechanical parts to hold them.
So, these are spectacularly good telescopes and they are available for us as soon as we can figure out what to do.
Some ambitions for the longer term.
When people say: "Well, what are we going to do after the Hubble Space Telescope?
What is the next visible wavelength or ultraviolet telescope for space?"
We say: "Well, let's have some imagination."
So these are 3 concepts that were provided to the National Academy of Science's survey a few years ago.
And here is one where we say: "Let's just get a very large rocket."
Then we could fly an 8 metre monolithic piece of glass that would carry this into space.
That would work beautifully.
If we can't get that, maybe make one out of many segments.
Maybe a 9 metre that would fold up.
If we have a big rocket and a great ambition, maybe we can make a 16.8 metre telescope with many segments and it would all be carried up in the giant rocket.
I see my reminder is reminding me that my time is over.
So, I will conclude by saying that there are many things to do with x-ray observatories.
We have one up there now that takes great pictures, sees black holes, sees, I should say, things falling into black holes, can't see the black hole.
We have ambitions for future x-ray observatories.
We have ambitions for even more future x-ray observatories.
And we have a project which is not currently going but we hope to revive it in some way to measure the gravitational waves from black holes as they merge.
So this was a project that European and the NASA were combining forces to build.
Right now it's not happening because we're waiting for revision.
Anyway this turned out to be too hard for us at the moment.
I think we'll get there eventually.
We will find eventually a new way of doing astronomy with black holes and gravitational waves.
So, thank you very much.
I will be happy to answer questions this afternoon.
(Applause.)