Swimmer Matz, Intria: I accidentally found your post on Facebook right after the James Webb Space Telescope took off. In it you write that as head of NASA’s ultra-lightweight structures, you have been involved in designing components for today’s most advanced space telescope. Could you please tell me what you were responsible for at that time?
Artur B. Chmielewski, Jet Propulsion Laboratory/NASA:- This was around the time the first exoplanets were discovered. At first they were large planets, then gradually they appeared smaller and smaller. A NASA official came to the Jet Propulsion Laboratory and said, “What if we discovered an Earth-sized planet in the habitable zone, examined it spectroscopically and discovered that its atmosphere contains compounds that make life possible? People will want to see a picture of it.”
He then asked us to make calculations of what size the telescope would have to be in order to capture such an image. At the time, the Hubble Space Telescope was the largest, and we calculated that the new telescope should be about the size of the National Stadium. In addition, there must be 27 of them in Earth’s orbit, and they must all target the same point, and only data from all telescopes will show the beauty of this planet. It is worth noting that these planets are far away and hidden in the light of the stars and darkness, which causes major problems in photographing them.
A month later, the same NASA administrator flew to us again, called me for the meeting and I told him in a regretful voice that I was sorry, but unfortunately calculations show that we need a telescope the size of a football field. I was expecting it to end at this point, but the NASA Administrator said – great, let’s start tomorrow because it’s hard work! Of course I was stunned. Believe me, I’m constantly striving to answer your question, so to cover James Webb, I just have to tell you how funny it sounded at first. (Laugh)
So we figured out that this telescope can’t be glass, steel or aluminum, it has to be made of a lightweight material like foil. Even this raised many questions and doubts given the size of the telescope. It was a very difficult task that we thought would take many years. I hired new engineers immediately after they graduated from school, because in my opinion the experienced engineers had a lot of contamination with traditional solutions. I wanted a whole new way of thinking about the band.
It was then that the concept of NGST (New Generation Space Telescope) was created, which is the basis for the James Webb Space Telescope. We came up with the idea that it must be very cold because it will work mainly in infrared, so it must be protected from sunlight. Then the same problem arose that was in the design phase of the telescope. Any heat shield known at that time would be very heavy, so we came up with the idea that it would be made of foil covered with a small layer of aluminum or gold. We assumed that the entire covering would consist of several layers made of this foil. Each of them is able to block 95% of solar radiation, and another 5% is allowed to pass into a different layer. The next layer contains 95% of the five passersby, and so on.
We assumed that four such layers were sufficient to provide the appropriate temperature for the telescope. It was 25 years ago when we started working on this project and for a year we built a 1:2 scale prototype working with IC Dover in Delaware. They had more experience with foil, because that’s what they made spacesuits for astronauts. It’s the image of this prototype found on Facebook. By building this prototype, we wanted to show that it works, but that’s not the end of the story…
Exactly, because you wrote in the same Facebook post that you hired an origami specialist to collaborate on the project. How was his knowledge useful in designing the heat shield?
– Of course, the point is that this cover had to be folded in such a way that it took up as little space as possible. At first, we thought it would be best to fold it into a regular harmonica, but in the meantime we’ve sent an inflatable antenna into orbit by the space shuttle. Astronauts photographed how they decompose in space. We then learned that the simple method of assembling such an antenna in ground conditions causes air bubbles between the assemblies. After taking equipment with such bubbles to orbit, where there is a large variation in atmospheric pressure, the method of propagating such an antenna is chaotic. Bubbles at all costs try to get out of the tubes they are trapped in and make the metallic foil decompose without any control. We compared it to the birth of a giraffe. We didn’t want it to be this way.
So, we wanted someone who had experience with how to put something together in a variety of ways to keep it space-saving. At the time, he was the world champion or runner-up in origami folding, an American college professor and a Native American, because people often think that Asians do it better. So I went to him to ask if he would like to help me figure out how to assemble this heat shield. We had an interesting conversation there, he was very knowledgeable, but I was wondering if I should engage him and give him a contract. Then a situation happened that I will never forget for the rest of my life. There was no GPS so I opened the map and asked him how to get to the airport. He showed me how to get there and then drew this map the same way. During the assembly, I saw a palpable pain on his face, as if I was doing something very terrible.
I asked him what is the problem? He replied: Awesome how I compiled this map! So I asked him how I should do it. He took the map, began to fold it, and after two minutes he literally made a cube. So I tell him he impressed me a lot, but how am I going to remove it now? He took the cube, tossed it with his finger, and then went back to the size of a normal map. At this point, I was determined. She postponed the trip to another time and immediately wrote him a contract.
– This story is really cool! If you count correctly, you were commissioned to work on the NGST back in 1997. That’s nearly 7 years after the Hubble Space Telescope shipped. What happened that work on the new telescope began so quickly? Is it a Hubble glitch or something else?
– This is standard procedure. In short, we’re doing one project, launching into space, and before it goes there, we’re developing another mission – in this case, a better generation telescope. So far, we’re making a better telescope concept than the James Webb Space Telescope. We organize meetings with scientists, they talk about scientific needs and so on. It was the same for the JWST project development.
In the first half of July, US President Joe Biden presented the first full-color image from the James Webb Space Telescope. I filmed the set of SMACS 0723. The Internet was of course in a state of great euphoria, and astronomy fans made no secret of their fascination. However, I’m curious how a NASA employee who worked on this part of the telescope many years ago felt at that moment… Can you share your impressions?
You know, when we discover new things, a person realizes how much he does not know. People now have a high opinion of themselves. They focus on material goods while trying to be better than others. One has a smartphone, another has a flat screen TV, and another has an electric car. When we look at people who lived 100 years ago from this perspective, we think they belong to a different era, and we consider ourselves better than them.
Meanwhile, we currently have no idea what makes up more than 95% of the universe. We don’t know what dark energy and dark matter are. For example, imagine that you only know 6% of your home. How can we with this knowledge say that we are better than these, that we are more enlightened?
Looking at James Webb’s Deep Field, I wondered how many galaxies there are, and how many stars there are, when we can know and understand all of this? I was also wondering when we will be able to photograph exoplanets to learn more about them? When you see something like this, you may feel offended in your own way. It is also sad that we are spending billions of dollars on armament to produce lethal destructive machines, with so much to discover, understand and learn about our past and future.
I must admit that your thoughts are very similar to those of Carl Sagan, who commented on the image of the Earth known as the blue dot. He also spoke of the fact that we live on a speck of dust suspended in streams of sunlight and struggle for small fragments of it almost aimlessly …
– I probably had such ideas, because when I started working at the Jet Propulsion Laboratory, it was Carl Sagan who often came to us. We talked about the various conquests of space, the discovery of life on Mars. For many years at the beginning of my career I’ve been listening to it, so maybe it reflects a little bit on my perception of reality even 30 years later…
– In conclusion, I would like to ask a purely philosophical question about whether, in your opinion, there is a chance that the James Webb Space Telescope, among the billions of stars in our galaxy, will find a planet on which we are sure that there is life there?
– James Webb (sighs) He won’t discover life, he won’t prove to us if there is life out there. However, it can help answer the question of whether there is a ninth planet that we are constantly looking for in the outskirts of the solar system. It can be difficult to confirm the existence of life itself, since it can only be confirmed by landing on a planet that we have such ideas. It is very difficult to discover life and prove that it is life and not something else… because how do you define life at all?
– If I were to do this now, scientists would assume that they were, for example, organisms that arose on the basis of carbon compounds. However, I wanted to involve you more in the context of spectral research. I read somewhere that Webb will be able to study the composition of the atmospheres of exoplanets.
– Yes, spectroscopy can be done, but imaging the planet itself is difficult because it always merges with the star. This can be compared to trying to observe a mosquito flying in front of a car headlight a few meters away from you at night. What do you do to discover this mosquito? You may be reaching out and blocking the light from the lamp. We talked about telescopes developed by NASA. Today, work is underway to create a telescope that will allow you to hide the light of a lamp, in this case a distant star, to observe the mosquito, that is, the exoplanet in question. The project involves sending a disk covering the glow of a star that will be some distance from the telescope. Anything to watch to see this exoplanet.
Interviewed by Swimmer Matz
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