Telescope Innovator Shines His Genius On New Fields Astronomer Roger Angel completely revolutionized the large telescopes that scientists use to look at the stars. Now he wants to use his mirror technology to make solar energy cheaper and more efficient.

Telescope Innovator Shines His Genius On New Fields

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This next story may help us understand how it is that brilliant scientists get their ideas. Scientists, of course, are simply trying to understand the world around them, but doing that requires tremendous leaps of imagination. Today, may a science student can explain the principles that make an airplane fly, but the practical way to do that was a lot less obvious when the Wright Brothers built their flying machine. As for Einstein's theory of relativity, it's hard even today for most of us to comprehend what it is, much less how he thought it up.

Even smaller achievements can be mysterious. How did James Wright dream up Silly Putty? NPR science correspondent has been working on a series that explores the minds and motivations of great scientists and inventors, and today his project, Joe's Big Idea, takes us to one of the most creative scientists alive today.

JOE PALCA, BYLINE: When I started this project, I thought I've got to tell people about Roger Angel. I reported on his work earlier this year, but there's so much more to say. He's an astronomer and he dreams big. He wants to peer back in time to the origins of the universe, to take pictures of planets orbiting distant stars. But before you can do those things, you need a telescope with a mirror big enough to capture the faint light trickling down to Earth from far, far away.

Twenty-five years ago, no one could build such a telescope. The glass you'd need to make a big enough mirror would be too heavy. So Angel thought, hmm, do you really need to make a mirror out a solid piece of glass? Maybe you could make the interior hollow like a honeycomb.

BRIAN SCHMIDT: Roger's always been someone who has lots of wild ideas. Some of them are superb. Some of them probably not so good, but he is incredibly creative.

PALCA: That's astronomer Brian Schmidt from the Australian National University in Canberra.

SCHMIDT: And that creativity coupled to sort of a genius is quite rare. So Roger's, you know, well-known around the world for having these brilliant insights of how to solve problems.

PALCA: Now, there's I've got to tell you about Brian Schmidt. He shared the Nobel Prize in Physics last year for discovering that the expansion of the universe was accelerating. He told me most scientists - and he includes himself here - aren't the brilliant problem-solvers Roger Angel is.

SCHMIDT: We tend to be the people who close out the game, and you know, do what is obvious and do it well. Where Roger is the person who really, you know, takes you and puts you into a new track and starts new ideas.

PALCA: So here's Roger Angel with this great idea for making a large lightweight mirror. But then he had to figure out how to do it, how to make a honeycomb mold, what kind of glass to use, and he had to find just the right temperature to bake the glass at so it would flow into the mold the way he wanted. Angel and his colleagues cast these enormous mirrors in a giant rotating furnace. This furnace looks a bit like an enormous enclosed merry-go-round.

The rotation helps the glass take on the parabolic shape it needs to focus starlight. It takes nearly a year to make one of these giant mirrors, so you want to make sure you get it right. The day I dropped by the University of Arizona last January, the temperature inside the furnace was just about to reach its peak at 2100 degrees Fahrenheit, a point known as high fire. Do you still get excited on the day of high fire, or not so much anymore?

ROGER ANGEL: Well, we've tried to arrange it that I don't get excited at all because if you are worried about something, then you should have done something about it ahead of time, right?

PALCA: Didn't somebody once say that genius is the infinite capacity for taking pains?

ANGEL: Oh, there's always a worry when you have, you know, it's a great big ball of very high temperature glass.

PALCA: Well, I was looking at it more on the positive side. I mean, is it still exhilarating at all?

ANGEL: Yeah. Yeah.

PALCA: Creative? Yes. Diffusive? No. Angel's not just interested in astronomy. In the past decade or so he's been thinking about global warming.


Roger Angel has an idea, and as ideas go, this is a pretty big one.

PALCA: I'm not the only one at NPR intrigued by Roger Angel. This is from an interview with Robert Siegel in 2006.


SIEGEL: His plan is to send a huge glass shield into space, and line it up so that it deflects two percent of the sun's rays bound for the Earth.

PALCA: That would counteract the warming effects of greenhouse gases, according to Angel. How big a shield would you need?


ANGEL: A bit less than 2,000 miles across, so it's pretty big.

SIEGEL: So something on the order of the United States from the Appalachians to the Rockies would have to...

ANGEL: Something like that.

SIEGEL: ...get up there. And how on Earth could people someday put such a piece of glass up in space?

PALCA: Of course Angel had already thought of that problem. He said a kind of magnetic gun that would launch the shield in small segments would do the trick. James Burge is a colleague of Angel's at the University of Arizona. Burge told me the thing about Roger Angel is that he doesn't just have a lot of ideas...

JAMES BURGE: He also has the ability to do the quick calculations or the very quick experiment to be able to see which ideas are good.

PALCA: Even Roger Angel will tell you that a 2,000-mile-wide glass shield is probably only going to be considered as a last resort. He hopes to prevent that day from ever coming, so he's begun to think about alternatives to burning fossil fuels. Now, Angel's a guy who knows all about capturing light, so solar energy was an obvious choice. There are plenty of systems out there that use mirrors to concentrate sunlight for electricity. The problem with all these systems is they're too darn expensive. They can't compete with low-cost electricity made from fossil fuel. Angel hopes to change that.

ANGEL: So that's what I've been doing for the last few years, is trying to figure out how to make good enough mirrors, you know, much lower quality than what we use for astronomy, and how to get those mounted so you can point them at the sun without too much steel and cost.

PALCA: To show me what he's up to, Angel took me over to an abandoned outdoor swimming pool on the University of Arizona campus where he's building a working prototype of his solar power system. It looks a bit like a giant box kite. A huge white steel frame holds a 10-foot square mirror. The frame is mounted on a turret that can track the sun. Angel has found clever ways to use bargain basement materials to keep down costs.

The mirrors are made from cheap mass-produced window glass. They're bent into the right shape using a second-hand industrial oven. A ball of pure glass helps keep the sunlight evenly distributed on the photovoltaic cells that make the electricity. The prototype in this swimming pool only makes a few kilowatts, but Angel told me he has some ideas of how he'd like to use that energy.

ANGEL: What's the most useful thing you can do with a few kilowatts of power? Well, you can charge your rechargeable car, your plug-in Prius. So I'd like to do that. It would be a real good feeling to be driving around town knowing the energy came from the sun.

PALCA: After a while I found myself wondering how Angel has such a knack for solving problems that stumped others, so I asked. Where do your ideas come from? Did you have an idea already today of some solution to a problem you've been thinking about?

ANGEL: Yeah. Ideas, I don't know what it is. I never have to sit down and think, well, I need to have an idea or anything. They just come pouring in.

PALCA: Maybe I shouldn't have been surprised that Roger Angel can't articulate where his ideas come from. It's probably like asking a fish where water comes from. I'd bet a world without ideas is just about impossible for Roger Angel to imagine. Joe Palca, NPR News.

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