By Edward S. Goldstein
In 2006, John C. Mather, a senior astrophysicist and project scientist at NASA’s Goddard Space Flight Center, became the first NASA civil servant to receive the Nobel Prize in Physics. Mather was recognized, along with George F. Smoot of the University of California, for the “discovery of the black body form and anisotropy of the cosmic microwave background radiation.” This work helped validate the big-bang theory of the universe. Mather and Smoot analyzed data from NASA’s Cosmic Background Explorer (COBE) satellite, which studied the pattern of radiation from the first few instants after the universe was formed. According to the Nobel Prize committee, “The COBE project can also be regarded as the starting point for cosmology as a precision science.” In July 2007, Mather, who generously has donated his Nobel Prize winnings to scholarships for science students, discussed his career at NASA and expressed his hopes for the future of NASA astronomy.
Dr. Mather, you have worked at NASA for over three‑fifths of the agency’s history, and you obviously could have worked elsewhere. What was it about NASA and the Goddard Space Flight Center that was so enriching to your career?
Proud scientist - John Mather meets the press at NASA Headquarters the day in 2006 he was informed about his Nobel Prize.
It seemed to me that NASA, especially Goddard, was the place where I could carry out the dreams that I had, which were to push forward an experiment that would measure the big bang radiation better than anyone had ever tried before. Therefore, it seemed like the perfect place to go.
It was a sort of place where scientists and engineers could rub shoulders and where very ambitious projects could be taken on, perhaps the only place in the world where you could do that kind of project, and that’s how it turned out. NASA labs are the pride of the world for things that we can do, where science and engineers meet together and say let’s do the impossible, and we will do it. That was the appeal to me then and still is the appeal to me now.
In your book, The Very First Light, you said it was important that the COBE satellite was done in‑house at NASA, that you had the scientists and the engineers working through the problems together.
Yes. It was very important. I can’t imagine that we could have ever done the COBE project, on contract where we would say, “Well, make a measurement that is a thousand times better than anyone has ever done before.” It just was impossible to write a specification for something you could buy. We had to develop it with a combination of engineers and scientists who could solve problems together.
What makes your colleagues at NASA special?
The colleagues that I have and that we have together here at NASA are people who self‑selected. They decided they wanted to do these amazing things in space. They were willing to make those choices that said they would be here whenever it was that they had to be here to make this happen.
Our space projects are very demanding. A person often has to work nights and days and weekends when the schedule requires us to finish something on time. We feel, I feel, that the entire world is watching us and waiting for us to do our thing and to get it right, and it is a tremendous opportunity. It is also a tremendous responsibility, and it has always been pretty clear that we do this together as teams and that it is the only way you could possibly do these amazing projects.
It takes a huge team of people. For COBE, it was about 1,500 people working together over the course of the project’s many years. For the James Webb Space Telescope we have over 1,000 people working right now, and organizing and managing this huge team of people to do this is clearly the greatest challenge of all.
You’ve made a point in your book (The Very First Light; Basic Books, 1996) and at the Nobel Prize ceremony of saluting your colleagues and mention the concept of teamwork.
Stockholm celebrity - Nobel Prize recipient John Mather meets University of Stockholm students after giving a science lecture during Nobel Prize Week in 2006.
Yes, it has always been clear to me that it was the team that solved problems, not one individual.
I just heard a quote that if you see a turtle on top of a fencepost, you know he needed help to get there. My experience from working with people is that you can have a conversation with someone or have a meeting with a group of people, and from that meeting will derive an answer to a question that no individual could have ever thought of by him or herself. Technical problems are solved that way very often, and managerial problems are solved that way. There is strength in numbers, but organizing those numbers is one of the great challenges.
The 20th century was characterized by physicists who created tremendous destructive power and those who provided us incredible insight into the origin in the universe, the category you fall into. What will the 21st century harbor for physicists, especially at NASA?
My crystal ball is quivering. I think that we are going to see a tremendous change over the years, not quickly, but over a long term, in what we can accomplish because we will be able to ask our computers to help us a lot more.
These days, knowledge for engineering resides in the hearts and minds of individual human beings and in team work, that we remember what we did last time when we create something together.
When we want to know how somebody did it 10 or 20 or 30 years ago, we can’t find out. Very often, the work was proprietary, and the person that did it worked for some company. Our engineering history is largely lost. I would think that eventually computers can save that [history] for us if we can figure out how to do that. I picture that maybe in 100 years, we will be able to come into the lab and the computers will say to you, “Well, I think I am ready to go to Mars. Can you get me this stuff?” and we will say, “OK, computer. We will fetch you this stuff. How much silicon do you want?” and something of that sort could happen. We just have no idea what the computers will eventually be able to do with us.
Tell me about your current work on the James Webb Space Telescope and in helping NASA chart the future of space astronomy.
The James Webb Space Telescope is the premier observatory for the next decade. We plan to launch it in 2013 as a follow‑on to the Hubble Space Telescope and also to the Spitzer Space Telescopes. Both of them have pushed our knowledge far beyond where we ever guessed they would go, and our new telescope will be bigger, better, and more powerful, see farther back in time, see into the dust clouds where stars are being born. We expect and hope that we will be able to even detect stars with planets going around them or in front of them, even pick up some signals from those planets, and learn about the possibility of how our Earth may itself have been formed.
We hope to touch the whole history of our own situation, how the Earth could come to be, beginning with the primordial material, and this is a tremendously exciting thing for us, but it is still only the beginning of the questions that people have in mind.
There are many huge questions that are being considered right now, and NASA is trying to decide which ones we can tackle first and with which partners. These questions range from how do black holes work; what the big bang was really like; what else can we learn about it from the residue that we have left; was Einstein really right; and are there gravity waves coming from the deaths of stars and black holes spiraling together to meet each other. There are a tremendous range of questions that are open and that astrophysicists have, and that is not even thinking about ‘let’s go visit a planet and see if there is life here in the solar system.’
There are plenty of signs of water here in the solar system. Mars was wet. We have very clear evidence of that. We have two satellites of Jupiter that are wet with ice covering the oceans. Recently, we have discovered that a little satellite of Saturn sends out little spritzes of water, and we see now water is or has been in at least four places besides Earth. If that is a prerequisite for life, clearly we should be going to look to see what is there.
I think a truly revolutionary discovery would be that we are not alone. Even if all we find is pond scum, which is most likely in hostile places like that, still the fact that there would be life elsewhere that may have had a separate origin from ours would be truly a world‑changing discovery for our understanding of our position in history and in the universe.
Well, goodness. I think if we want to see life or signs of life on planets around other stars, number one, we have to see the planets or see radiation from the planets, and we have a series of things we have conceived of to try to do this.
The ones we already know about, of course, we have discovered with existing telescopes such as the Hubble Space Telescope and Spitzer Space Telescope. We are about to fly one called the Kepler Mission that will observe 100,000 stars. We will use Kepler to see if a planet happens to go in front of the star.
We will follow up with bigger telescopes on the ground to see can we learn the detailed properties of these objects. Then after we have a list of candidate objects, the James Webb Space Telescope will surely point at them and see what we can learn. After that we have ambitions for bigger and better things.
There are other ways to find planets around nearby stars, watching the motions of the stars as the planets pull on them. There is a mission called the Space Interferometry Mission that was planned to do that, and we had to stop because we didn’t have enough money, but eventually, we will have to either do that project or find an alternative because that is a very important technique to try.
When we know where there is a planet to look for, we also have at least three different concepts for how to see it directly. One is to build an almost‑perfect telescope and then block the light from the stars, so you can see the planet next to it. It is called a coronagraphic telescope. A second idea is to build a synthetic telescope with several separate telescopes that combine light in a central place that is called an interferometer, and that would operate at infrared wavelengths, and a third kind would have a combination of a telescope with a remote obscuring device that we call an occulter. Such a distant object could cast a shadow of the star on the telescope, and you could see a planet next to it. We have these three, and I think we will have to find out which one is the most feasible, but all three are, in principle, capable of showing us light, direct light from a planet like Earth around a nearby star.
With enough information about such a planet, you can look for the chemistry of the atmosphere of that planet, and people have recognized that if you could find the chemical signature of three different gases ‑‑ carbon dioxide, water and oxygen ‑‑ that that combination would be unlikely unless there were photosynthetic life happening on that planet.
We have thought of techniques to find the signs of life on a planet around another star… It may take us 10, 20, 30 years before we know these kinds of answers, but that is still within the time frame of people who are coming through school today.
I think within the lifetimes of many of us, that we will know whether we are alone or not with respect to planets outside the solar system.
Ever since Frank Drake came up with his ideas about searching for radio signals from distant stars, that has been an intriguing, but frustrating, experiment. What do you think about the future of that kind of search for signals?
This is the Search for Extraterrestrial Intelligence, or SETI. There are quite a lot of different opinions about what is the right way to hunt for civilizations that might be sending out signals.
The one that we have been trying is relatively cheap, and people around the world have their computers helping to analyze the data. Everyone can get a screen saver that will spend your computer’s spare time hunting for signals from other planets.
I think we knew when we started off that the odds of success were very small, but that the consequences of discovery were truly immense. It started off as a government‑sponsored project. Eventually, it was switched over to private sponsorship, and it is still going. There are a lot of people who believe that this is very well worth pushing, even though the odds of discovery are small, just because it is so important.
On the subject of government sponsorship, you wrote in your book, “There will always be scientific questions simply too difficult or of limited commercial benefit. Fortunately, there exists in the U.S., a formal competitive process for Government funding of scientific projects that values originality and new perspectives. Had such a system not been in place, COBE would have never been launched. In the U.S. only, NASA can undertake certain large scientific projects such as looking back at the beginning of the universe or speculating about the future as we monitor the loss of ozone layer. NASA has opened new windows on the cosmos with the Hubble and gamma‑ray observatories and on Earth by monitoring the size of polarized caps to determine whether global warming is significant.”
Do you think that NASA will always have a role in these kinds of fundamental scientific inquiries?
I think so. I believe we are capable, and we may be the only agency that is capable of taking on these very large questions. Some things really require the perspective of looking at Earth from space or looking out into space from space because of the particular kinds of questions that we are asking, and so far, NASA is the only big agency that does this.
Other countries in the world could take this on, but at the moment, our NASA is much bigger and more capable than others [space agencies] and enjoys very strong public support, which I think is far beyond what is available in other countries as well. I think we can be very proud of what we have accomplished.
We look back in history, and we think this country was founded in part by a scientist, Ben Franklin, and a future president, Thomas Jefferson, who was very fond of science and sponsored the first national science expedition to go out and explore the new territory, the Louisiana Purchase, and they would be so proud and thrilled to see what our country has accomplished following on with science and the engineering miracles that have happened as a consequence. I think they never would have guessed [what happened], but they would still be thrilled to see what has been done.
How did you get to NASA?
I actually got to NASA by trying to avoid what happened to me. In graduate school, my thesis project was to measure the cosmic microwave background radiation. But it didn’t work very well, and it was very difficult, and I thought my destiny was to be a radio astronomer.
As it happened, the radio astronomer that I wanted to work with was a NASA person in New York City where we had a small radio astronomy laboratory, and I went to work there [Goddard Institute for Space Studies]. Right then NASA announced this opportunity to propose new satellite missions, and I thought, “My thesis project would have worked better in space, so let’s talk about it.” That’s how I was drawn back into the subject of cosmology because NASA wanted to do satellite missions.
I went from my postdoctoral position directly into the fire and took on the job of working on COBE. That is when I moved to Maryland, to work at the Goddard Space Flight Center.
On the morning of Oct. 3, 2006, you were awoken with a phone call announcing your Nobel Physics Prize. Can you tell me about that call?
It was from Per Carlson, the chair of the Swedish committee that chose the winners. Soon I was receiving phone calls from reporters and family members and after talking for an hour and a half I realized I was never going to have breakfast at this rate, and I better take the phone off the hook and just proceed with my day. Within an hour, my neighbors had decorated my house with balloons. A lot of people were watching to see this event happen, and I was sort of pretending that this might happen and it might not. I was trying to pretend this was going to be a great surprise.
At a celebration at Goddard the next day you said, “This is us, this is my family here, these are the people I love.”
Yes, I did. That was exactly how it felt, and it still gives me goose bumps to remember that moment because it is my family. These are the people that I have worked with for so long, and we have given so much to each other to make our dreams come true.
What was it like in Sweden?
It was a wonderful time. The Swedes had filled up my calendar with two or three major events every day, with a lecture or an interview or sometimes two or three of those every day. There were also banquets and parties. On the Nobel presentation day, I sat with the queen of Sweden, and I talked with her, and my wife got to meet the king and talk with him.
During the Nobel ceremony period, you met your fellow laureates. What did you learn from each other?
I learned a little bit about biology because there is an awful lot more to learn, but one of the stunning discoveries of biology that was recognized this year is called RNA interference. It turns out the genes in our bodies can be turned off by the reactions of our bodies to incoming things, and there is an even greater surprise that this can be inherited. This goes against the whole picture that we have from Mendel’s discovery of genes with planting peas back in the 19th century because we had never been able to show before, that there was some inherited genetic change, but it is now recognized in some cases that that can happen.
It is not just a mixture of random genetic codes that happens. There is an actual reaction to incoming infections or various things that happen to us. That has changed a lot, and it is within just a few years, it has become a multi‑billion‑dollar industry to use this technique to help people.
I was reminded about the practical nature of biology and the theoretical nature of astronomy, and nevertheless, astronomy is really an exciting thing for people because it tells us how we got here, and people are determined to know how we got here.
If you drive through the countryside in this area of the country, everywhere there is a little sign that says a battle was fought here or Morse’s telegraph was tested right over here, just north of Washington, D.C., and people are very interested in our history. We fight over the proper interpretation of it, and it is very close to our hearts. Astronomy works on that part, and biologists do, too. They tell us how we got here as well, but then they also have the applied biology that we all care about so much for daily survival.
When you travel through the countryside and you are out there on a moonlit night and you see the vast expanse of stars, what are you thinking in your heart?
When I look at things, almost immediately I am thinking how they are made. When I look at a piece of plastic, I think of the carbon and the oxygen and the chemistry and the history of those atoms and how they came from stars, and I’ve just immersed myself in this for so long, that that is almost automatic for me, and I look at the stars from a dark night, and I say, “Oh, those are our ancestors out there. I wonder where we are all going together. I wish we knew how this all worked,” and it is this huge open question for me, at the same time that I am ruminating on how it all happened.
Do you also feel any emotion, given the fact that you, by happenstance and through your skill and training and good genes, are alive at a time that you were able to make this discovery?
It’s funny. I feel more strongly about the astonishing nature of life than I do about the fact that I did something. I am just amazed at our human organizational systems that enable this to happen.
I feel somewhat personally blessed that I am here right now, but I am also amazed that starting from a couple of hundred years ago when our country started and people never guessed that you could cross the country in less than a year, and here, now our ideas will cross the nation in an instant. I am more amazed than I am taking personal credit for anything. I am just amazed at our world.
But don’t you feel at least fortunate that your life has taken place at the time that you were able to accomplish your discovery?
Yes, I do. I feel very fortunate that I have been part of the discovery process because it gives me great personal pleasure to discover things, and there’s something new to read about every day.
I love reading the scientific news because it is always a wonderful discovery every day, and it is much more fun to me than hearing about the latest fires and disasters that are typical on the news. To me, science is a very inspiring and enjoyable thing, but also opens up the prospects for a completely unimaginable future, and I am very curious to see what is going to happen from here.
You are supporting scholarships for science students, and you speak to science students all the time. Do you share the worry of some that American students are falling way behind?
Some American students are still among the most brilliant in the world. A large number of American students do not get the opportunity that they could have to really learn and appreciate science and to exert the technical and scientific leadership that I think our country depends on for our own prosperity in the future.
I am very glad when people come to this country because they feel it is the land of opportunity, and scientists and engineers come from everywhere to work here, but it makes it just slightly worrisome that our own children are not seeing all those opportunities and that actually the majority of scientists and engineers today are being born and trained in other countries. It should make us all a little bit nervous that the position of great prosperity that we currently have may not last forever if we don’t keep on doing what it takes to be supporting and attracting bright young people to do what we have to do.
Can NASA have a special role in inspiring this next generation of explorers and scientists?
It seems to me that NASA has a very public role in doing this because it’s an area which attracts public attention like no other.
When we send a person to the moon again, when we send people up into orbit, when we discover planets around other stars, when we see the picture of the big bang itself, people can get excited about that, that may never understand it, but some of them will actually say this is so exciting, I want to be a part of it, and maybe they will go on to become a biologist or who knows what they are going to do. Maybe they will just think that this is the most exciting thing, and they will vote to support it later, but all of these things are part of our leadership position in the United States, and I think NASA has a tremendous role to play in making sure that that continues.
What was your reaction when Stephen Hawking commented on the COBE findings and said, “It was the discovery of the century, if not of all time.”
I thought, “Well, Stephen, that is very nice of you to say that, but there have been other really exciting and important discoveries before this.” He was talking specifically about our measurement of the hot and cold spots in the big bang radiation which show us not only is the big-bang theory right, but also, it gives us the map of the seeds of the structure, the things that will eventually grow into galaxies.
I was very appreciative that he liked our discovery, but I also thought, “OK, well, relativity, that was pretty important. What about Albert Einstein?” I think I would grant him priority over our discovery, to tell you the truth.
You sometimes speak to church groups and you have written about this intersection of spiritual or religious interest in our creation or the creation story and what science can help inform humans about creation. What kind of questions do you get about this subject, and how do you respond to questions from people who ask you to produce a simple answer for them?
That is actually an interesting question because when you talk to people about their understanding of history and the universe, everyone has an opinion, and people care deeply about this. For many, many decades, people didn’t agree with the big-bang theory. They thought something else must be true, and generations of astronomers thought it must have been the steady‑state theory. Einstein didn’t like the idea. Scientists have fought one another over what is the right story.
The general public has many other opinions. We have our religious traditions coming from many thousands of years, and I think to myself, well, you know, if Moses had come down with tablets from the mountain that said, “And guess what? There are protons and neutrons, and they are made out of quarks,” people wouldn’t have understood what he said. So he didn’t.
We are discovering what the universe is really like, and it is totally magnificent, and one can only be inspired and awestruck by what we find. I think my proper response is complete amazement and awe at the universe that we are in, and how it works is just far more complicated than humans will ever properly understand. This is where sort of a faith in how it is working comes to be important to people, and some people’s faith says all the world is falling apart, we are all going to heck, it is getting terrible here, and it is getting hot. Other people say I see the children of today, and they are going to build tomorrow, and I have faith that they are going to do the right thing. That is where I am about it.
I see the brilliant young people today, and they feel to me much smarter than I feel that I was then, and I think they are going to do a good job. I meet the youngsters that are studying science. I meet kids that are scholar athletes, getting scholarships for the most astonishing things. I think the world is going to work out. We will solve these difficult problems that we have in front of us.
On COBE, you had to solve many problems. Tell me about how you had to move very rapidly to fit your satellite on a new launch vehicle and to reduce your satellite’s weight by 5,000 pounds after the Challenger tragedy.
That was a terrible tragedy, and what we did in our project was we didn’t stop working a minute.
We knew that we had something that we had planned to do, that was really important to the country, and we just had to find a way to get it going, even if the Challenger had shown us that the space shuttle wasn’t going to take us into space.
We started looking around. Our project managers hunted around the world for alternative launch vehicles, and eventually, we found that the Delta rockets which had been made, but mostly discontinued back in those days, could still be found, if we could find enough spare parts. We had to find the spare parts and get permission to use the old parts, and then we had to say, “OK, well, we had a 10,000‑pound design, what does it take to get it back onto the Delta rocket?”
It sounds heroic, but in truth, the Delta rocket was able to take us directly to the orbit that we needed, and the space shuttle could not. That was the technical fact that made it possible to solve this problem.
We took about eight months to figure out that it was possible, and then NASA said, “OK, it is possible to do it, and do it as fast as you possibly can.” We did. It was a very amazing process. People were up nights and weekends for months on end to make this thing go from impossible to possible, and it worked.
Two days after your launch in November 1989 you got a phone call early in the morning telling you that a gyroscope on COBE had failed.
Yes. We did have a gyroscope fail, and my first thought was, “You mean we’ve lost the mission?” It was the fear that I had. I had just gotten home at 4 in the morning, but I got back up, put clothes back on, and headed back to Goddard and found out how we were doing. As it turned out, we were lucky in our bad luck because ‑‑ and this isn’t exactly luck ‑‑ our engineers said, this is something that could have happened, and they planned for it. So this was a challenge that they had already anticipated and taken on. The spacecraft was safe, and we had enough gyros to keep on going. We were very lucky in our unluck, but we planned for that luck.
Tell me what happened when you presented the COBE results to a meeting of the American Astronomical Society in the spring of 1990?
I showed this one chart, and the entire room of astronomers, which is maybe almost 2,000 people, they stood up and they cheered, and it was not something I had expected. A little while afterwards I thought, “Well, I knew that was the right answer. How come they didn’t know? Why are they cheering?” And finally, it occurred to me: they didn’t know that was the right answer.
We had had some decades of getting wrong answers about this measurement, and so the whole idea of the big-bang theory had been in some doubt, and so when we got the measurements that fit exactly on the theoretical prediction for the big bang, this tremendous sigh of relief went through the world as well, and that is what I think they were telling us, as well as it was a beautiful measurement.
You mentioned that astronomy doesn’t intrinsically provide benefits to people. Yet, we would be much poorer without it. Is that a hard argument to make to people who tend to measure the cost of everything?
I don’t think so, really, because it is the actual truth. This is why people care about stuff. We spend money on plenty of stuff that actually has no importance besides culture. How important is it really that our team wins throwing a little ball around the field? But it is immensely important to people, and it seems to me that something that changes our entire world view is immensely important for decades, hundreds, thousands of years, and so I am proud that we can accomplish it as we do, and I think most people that think about it see it that way in the end as well.
Also, I like to remember that from astronomy have come many unexpected benefits. Who knew that this was going to happen? The Space Age began for curiosity. We and the Soviet Union launched little satellites to explore the upper atmosphere and looked for what was just above Earth in space, and we had immense surprises, and then our nation was rather upset by being beaten into space, and so we invested extraordinary efforts into recovering.
We said science and engineering are our future. We brought up generations of young people to become scientists and engineers, and we look around at our world now, and it is filled with the results of that effort. It was something that started off because we were curious, and now our entire world is different.
In the 1960s, there were scientists like Richard Leakey and Jacques Cousteau who had worldwide acclaim. Is that the case today? Do you sense that?
Well, I don’t pay very much attention to who is a famous scientist, although maybe I should now. But Jacques Cousteau was one of my heroes. I think the very first book that I ever bought was by Jacques Cousteau, and so I was just thrilled with the idea that you could strap on a tank of compressed air and go swimming under water and see stuff. He was one of those early space explorers, as far as I was concerned. Before we could go into outer space, we went into the water.
I don’t know how famous scientists are now. There is no Einstein right now, but Steven Hawking I think comes close to sort of tantalizing us with the mystery of what are space and time.
When you went to Sweden, one of the things you wanted to mention was that it is important that 14 Nobel Prizes have been given on the subject of light. Why?
I thought it was interesting that so many scientists and physicists have been studying light, which you might think, well, this is pretty simple, everybody knows about light waves, but we don’t, and light turns out to be one of the most fascinating and interesting topics in science, even though it starts off seeming to be very simple. I just thought that was interesting.
Thinking of NASA’s next 50 years of space astronomy, where do you think we will be placing the telescopes? How difficult will it be to make the quantum leaps like you said, the computer that will order up the new set of instruments?
I think a lot of our telescopes are going to be going into deep space near the [gravitationally balanced] Lagrange points… But for every observatory, we are going to have to decide, “Is this something where it is important to keep it near home, so we could fix it, or put it out into deep space near the Lagrange points where it is protected from various other kinds of trouble?”
Maybe over the years, we will develop the ability to go visit those things in deep space and fix them. I think the robotic revolution is continuing. It has turned out to be more difficult than people hoped, but it is still going, and Ph.D.s are being given every year for robotic studies, and we are beginning to get household robots that vacuum the floor, and I think eventually, the commercial world and the academic world will produce things that NASA wants to use in space.
It is too early for us to be sort of making a space‑worthy version of a robot yet, sort of the general purpose robot that you would have seen in science fiction stories. But robotic servicing for space missions is already possible, and we looked into it very seriously for the Hubble Space Telescope. And we almost decided to do it, and we know that it’s feasible, and with time, I think it will get easier.
What about astronomy on the moon?
There are a few things which astronomers recognize as special on the moon. One is a measurement of the distance to the moon, which might seem to be uninteresting, but as it turns out, very, very precise measurements are a test of relativity, and we can find out of Einstein was right or if there is another fifth kind of force in the universe besides the ones that we know about. We recognize that one is a good one. We have been doing it for some time, but we could do it a lot better.
The other thing that is special on the moon is very long wavelength radio telescopes. As it turns out, if you want to build a radio telescope that works at wavelengths longer than about 30 meters, then you can’t do it on the ground because the atmosphere of the Earth actually, completely reflects back those waves. So you just can’t see from here. So there is a whole piece of the universe that is almost unknown, and it is the radio astronomy and those longer wavelengths.
Now, if you do want to put a telescope in space, it turns out this is a very noisy place to put one, also, that Earth sends out its very intense radiation, and so does the sun. So where would you really like to go? You would really like to put your wonderful new telescope on the far side of the moon and use it for the two weeks of the month when it is also in the dark. So this is a terrible engineering problem, but a wonderful scientific opportunity. So I think that is the other big opportunity for us, for astronomy on the moon.
Most of the telescopes that look like telescopes, the ones that you think of like Hubble, actually work pretty well without being on solid ground and actually better. So that’s where we put them.
You have worked on COBE, now Webb. How would you like to cap off your career?
I would like at least to use the James Webb Space Telescope for observations and take on some new mystery of the early universe and try to make sense of something out there. Right now, while we are busy building Webb, I am not thinking very much about what we are going to use it for, but eventually, I want to use this wonderful tool, and I would love to make some new discovery with it.