By akademiotoelektronik, 26/08/2022

The space is changing, and the webb telescope is only the beginning

The wait is long and painful for astronomers. The James Webb Telescope is about to make its final orbit around the Sun at "L2", a point in space about 1.5 million kilometers from Earth. This point allows the telescope, the most sensitive and sophisticated instrument ever placed in space, to keep all major sources of heat and radiation close, whether the Sun, Earth, of the Moon or the telescope's electronics and attitude controls, away from its tennis court-sized heat shield.

Everything must go perfectly for the mission to be a success. The heat shield, a stack of five impossibly thin sheets of a material called Kapton, the thickest of which is only five-hundredths of a millimeter thick, has countless failure points in its machinery. The primary mirror, the first telescope mirror ever sent into space as individual moving segments, must deploy perfectly for the telescope to capture hoped-for glimpses of the universe. The reaction wheels, the dozens of actuators that move and go around the mirror segments, a unique refrigeration system, the final corrective burn that puts the telescope into its L2 orbit – it all has to work perfectly, because no current space technology will allow NASA to send someone to fix it.

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Webb is an amazing gamble, a $10 billion megalith so intricate and promising it seems like a hubristic provocation against the gods. What is worrying for the superstitious is that everything seems to have gone extremely well so far. The launch from Earth was so perfectly oriented that NASA announced that it would need less fuel for the corrective burns, which could extend the ten-year estimate for Webb's operation by several years.

Shortly after Webb's perfect launch into space on Christmas Day, The Times of Israel caught up with Michael Kaplan, a former NASA engineer who led the space agency's telescope planning in the 1990s and was one of Webb's initiators, for a video interview from his home in Colorado. He explained how Webb had already pushed the limits of humanity's engineering capabilities and will soon greatly increase our knowledge of the early universe, why Israel's innovative culture can paradoxically make the country failing in terms of engineering space, and what space travel should look like in the near future.

Kaplan, 66, has had a career in aerospace, spending a decade at the Naval Research Laboratory in Washington, where he worked on space radars to counter Soviet intercontinental ballistic missiles, then worked for NASA , Ball Aerospace (the Colorado company that built Webb's now famous honeycomb mirror), and Boeing, where he worked on planetary probes. Also, he spent five years in Israel, the country of which he became a citizen and where he worked closely with SpaceIL, the Israeli Space Agency, and the Israeli aerospace industry.

Kaplan returned to the United States in 2015, where he worked on new space missions and weather satellite systems at companies like Raytheon. He is now vice-president of Belcan, a major American engineering company and government contractor.

Michael Kaplan, former engineer and NASA executive. (Courtesy)

The interview, edited for clarity and length, kicked off with the incredibly brave decision to build and launch such a complex telescope.

The Times of Israel: You said there is an unwritten rule in spacecraft design: “You want the minimum number of moving parts. Anything that moves can break down. We've heard about the primary purpose of the James Webb Telescope, which is to glimpse the beginnings of the universe, and the excitement and anxiety its launch has generated in the astronomy community. But to do that, Webb must have hundreds of moving parts, including hundreds of individual points of failure that, if they don't deploy and function perfectly, could wreck the entire estimated $10 billion mission. Why is the Webb project so important? Why is the game worth the candle?

Michael Kaplan: When Hubble was launched [in 1990], people protested at the launch pad because they feared that Hubble would see God, as if he were behind the clouds, and that Hubble was going to do it. reveal. Photos from Hubble have graced magazine covers because they look like art. There is something profound and wonderful about the natural universe in all its glory becoming art.

But Hubble was limited by the size of its aperture, the sensitivity of its detectors and instruments, and the fact that it was not cold enough.

Most people don't know this, but Hubble actually only observes about 35% of the time. The other 65% of the time it avoids the Earth, Moon, and Sun, because we don't want light from the Earth, Moon, or Sun to enter the telescope and damage the instruments. It also cannot see wavelengths longer than near infrared. The oldest parts of the universe (whose light has traveled the longest in ever-expanding space, and whose wavelengths have therefore lengthened the most) appear to us to be infrared-shifted.

To see in the far infrared, to see the light traveling towards us from the earliest universe, your instruments must be extremely cold, because hot objects shine in the infrared and blind us to that faint light. Thus, to see further than Hubble, Webb must see further into the infrared. It should be cooler, more sensitive and carry a larger primary mirror than its predecessor. How did such an ambitious project come about?

Although talk of a successor to Hubble began in the 1980s, it was in the early 1990s, shortly after Hubble launched in April 1990, that more serious planning began. A committee of scientists called “HST and Beyond,” led by Alan Dressler at the Carnegie Observatories, asked themselves, “What do we do after Hubble? »

At the time, I was the head of advanced astrophysics programs at NASA headquarters. My job was to plan future telescopes. So I met with the committee and made a presentation on the current state of technology. The committee said it wanted to search for baby galaxies and needed to launch an infrared telescope with a four-meter primary mirror. (Hubble's was 2.4 meters.) Why four meters? Because it was the biggest mirror we could fit in an existing rocket.

Stellar nursery LH 95 in the Large Magellanic Cloud taken by the Hubble Space Telescope. (Credit: NASA/HubbleSite/Public Domain)

At the time, NASA had a relatively new administrator, Dan Goldin, who came from a company called TRW, now part of Northrop Grumman [the contractor who built Webb]. Dan was a transformational and highly controversial leader. He had a different way of looking at things. In the world of planetary science, he wanted missions to be smaller. He coined the phrase “faster, better, cheaper”. But small does not work for astronomy. You can't make telescopes smaller if you want to see more. So he challenged us with the next big paradigm shift for astronomy: breaking the barrier of a single mirror.

He was a technologist. When he was back at TRW, they had built advanced programs for the military that involved segmented optics. There were ground-based telescopes and some were designed to operate in space at sub-millimeter or radio wavelengths that were not one-piece but made of hexagonal pieces fitted together. He therefore knew that this technology existed and had seen the problem solved in the submillimetre wavelengths.

At the 1996 American Astronomical Society meeting in Tucson, Arizona, I sat in the front row. Next to me, Alan Dressler. Dan is on the podium. He looks at Alan and says, “I see Alan Dressler here. All he wants is a four-meter optic… And I said to him, ‘Why are you asking for something so modest? Why not go up to six or seven meters? »

Then Alan said, “Why not eight? Dan bangs his fist on the podium and says, "Sold." As if it were an auction.

In this image released by NASA, Arianespace's Ariane 5 rocket, with NASA's James Webb Space Telescope on board, lifts off Saturday, December 25, 2021, from the Guiana Space Center in Kourou, French Guiana. (Credit: NASA via AP)

So the Next Generation Space Telescope, NGST, as we called it at first, was originally envisioned as an eight-meter telescope, and it was to be realized by segmented optics .

But we had no idea what it would be made of. All telescopes that had flown in space before, and Hubble was by far the largest, were made of glass that was back-thinned by water-jet or grinding, because glass is heavy.

Here are some quick calculations for our readers. Hubble's 2.4 meter glass mirror weighs 828 kilograms. At this weight per square meter, a mirror 8 meters in diameter – or 10 times the surface – would have weighed more than 10 tons.

We therefore considered silicon carbide, composite materials covered with a very thin layer of glass and beryllium, which ended up winning. Our goal was to divide the mass density by ten. [With success: Webb's beryllium mirror weighs about 20 kilograms per segment.] The competition took place over several years. We have invested approximately $50 million in the development of these technologies.

In this September 29, 2014 photo made available by NASA, Larkin Carey, optical engineer for the James Webb Space Telescope, examines two test mirror segments on a prototype in the giant clean room at Goddard Space Flight Center in Greenbelt, North America. Maryland. (Credit: Chris Gunn/NASA via AP)

We also had to find a way to deploy the mirror. Should a robot arm distribute the hexagonal panels like a deck of cards in space? Should he bend? How to make a whole from the parts?

The challenge was to operate the adaptive optics at cryogenic temperatures, at 40 Kelvin. All actuators, fine motors and sensors had to operate at very low temperatures. The sunshade wasn't seen as a big challenge initially, but eventually it was in terms of deployment reliability. Initially, we thought the umbrella would be inflatable.

When you add up all the mechanics and put it all together, the overall problem of running a complex deployment with 100% reliability was a challenge, and the only way to solve it is to train. No one had ever done anything so complex before in space. We knew it would be complicated, but we hadn't anticipated this magnitude of complexity.

Normally you mitigate the effects of a moving part by having a backup. If one primary engine fails, you have another engine. But not everything can have a backup. When you deploy a line that pulls and creates tension on the sun visor, you cannot have another engine on such a piece.

We went from "eliminating moving parts" to "learning to live with moving parts".

[Webb engineers] believe that, within the limits of our knowledge as humans, we have analyzed and tested just about everything we could. You put the greatest minds on it, you have a plan, and then you just have to have faith and believe it's going to work.

Of course, what makes all this complexity terrifying is that the only way to keep the telescope cool enough to see the far infrared light of fledgling galaxies is to station it about a million miles from Earth , four times further than the Moon, where it will not be possible to repair it with existing technology. So what are the advantages of the L2 point that justify giving up any chance of fixing an error in such an incredibly complex machine?

It is always dark at L2, as a large umbrella the size of a tennis court blocks out light from the Sun, Earth, and Moon. Half of the sky is therefore always in darkness. This means that, unlike Hubble, you're doing science all the time. In five years, you can have as much observing time as Hubble has in 15 years, because Hubble only observes about 35% of the time. So even if the primary mission is shorter in duration (at the time of launch, NASA estimated the probe's lifespan to be 10 years before fuel depletion), it will be very, very effective.

This combination of images from an animation made available by NASA in December 2021 shows the unfolding of components of the James Webb Space Telescope. (Credit: Conceptual Image Lab via AP)

We're starting to see why everyone is so impatient. So many risks and so many promises. Let's talk about you. Trained at Princeton, Department of Defense, NASA, Boeing. This is not the usual CV that one encounters among olim [immigrants to Israel]. What suddenly awoke in you the desire, in 2010, to go to Israel?

It was the fall of 2009. I was living in Boulder, Colorado. The base of the Rocky Mountains is right outside my window. I moved here to work for Ball Aerospace. I left Ball and went to work for Boeing on planetary missions. Everything was going well.

But my youngest son was in college at the time and was starting to want to convert to Christianity. He had become involved in a fellowship that was winning him over – he was talking about Messianic Judaism.

I asked some friends what I could do to shake it up a bit. They said to me, “Take him to Israel. “I had never been to Israel before. I thought about it, but it was always either Israel or Yellowstone or Israel or the Grand Canyon. It never topped my list, which is probably true for most American Jews.

New immigrants from North America land at Ben Gurion Airport after a flight from New York chartered by Nefesh B'Nefesh, July 19, 2016. (Shahar Azran)

So I planned a travel. I talked to my rabbi and others about how to have a spiritual and meaningful journey. Their first piece of advice was, “Don't stay at the hotel. Find rooms to rent in people's homes. You will have a better connection. »

I wanted to awaken the Jewish part of my son's soul.

Long story short, it didn't work on him, but it worked on me. I returned home and my friends told me that they had sensed a change in me. I am not religious but I am spiritual. I didn't know what aliyah was. I met my rabbi, and he said, “Oh, you are going to make aliyah. I replied, "I don't know what it is, but I'm thinking of going to Israel." »

Over the next five years, you met the entire upper echelon of the Israeli aerospace industry and space program and became deeply involved with SpaceIL, the Israeli team that entered the Google Lunar X Prize for land a space probe on the Moon. The probe, called Beresheet, finally crashed on the Moon in April 2019. How does the Israeli space world appear to someone coming from NASA and Boeing?

I spent five years trying to find my role, but I did not find the necessary openness to an experienced person coming in with different points of view.

For example, I told the SpaceIL team, “You're not thinking about redundancy the wrong way. Certainly, no human life is at stake, but you will be on the international scene. All the school children in Israel will watch the moon landing. You need to think about what can go wrong and spend the extra money to make sure you've identified the failure modes. »

One of the last photos taken by Beresheet before it crashed on the Moon, April 11, 2019. (Courtesy SpaceIL)

Looking at Beresheet's moon landing [in April 2019], you could exactly find out what went wrong. You see the readout on the screen showing altitude and airspeed, and at about two or three miles up, all of a sudden the airspeed drops to zero.

I think the inertial measurement unit has failed – the sensor that tells you you're moving. If the sensor says you're not moving, then the spacecraft's computer says, "We're on the ground, we've landed," and shuts down the engines. A crash. I was like, “It must have been a $100 coin. »

They had a wonderful vision, but I looked at their program when we first met in 2011, and saw a complete lack of understanding of the cost of this program. They had raised $24 million. So I said, “What are you using for fuel [at this price level]? I think you are using 'unobtainium'. »

I had worked on lunar probes at Boeing. First you figure out how much fuel you will need, size the gas tank, then size the engines. A probe is a flying gas tank. I asked the Boeing team, "What is the minimum cost to land something on the Moon?" And the answer was $150 million. Because of fuel, size and how everything fits. And if you put 50 kilos of cameras and scientific instruments, it will cost more.

It's done with an experienced team. There, it was an inexperienced team. They're smart guys but they've never done this before. I calculated the difference between labor costs, mission complexity, and inflation and came up with a price tag of $100 million. I spent the next three years banging these guys on the head and asking them, "Where's the missing $76 million?" Sheldon Adelson came to visit us and they were going to ask him for another $8 million. I said, "No, ask him for 80. He's got them." And if there's any left, tell him you're going to build the Sheldon Adelson Science Museum. »

Launch crews monitor the countdown to the launch of Arianespace's Ariane 5 rocket carrying NASA's James Webb Space Telescope, Saturday, Dec. 25, 2021, in the Jupiter Center at the Guiana Space Center in Kourou, French Guiana. (Credit: NASA/Bill Ingalls/NASA via AP)

It ended up costing $100 million. But they lost years. They ended up transferring the project to IAI [Israel Aerospace Industries for the construction of the probe], where they had real professionals. It was a wonderful and noble cause, but you can't do that with volunteers. They needed help. But there was pride. The leaders did not want to listen to the advice of those who knew how to do these things.

Was SpaceIL, a unique and particularly bold initiative, representative of Israeli aerospace in general?

I've seen it in other entities. I have seen mistakes made that I cannot comment on.

I found this very frustrating. I think if SpaceIL had listened from the start, the mission would have been a success. The leaders had no idea how to conduct a space mission, they thought you could put people in a room with pizza and solve the problems in a weekend.

In this file photo taken on December 17, 2018, Israel Aerospace Industries Space Division Director Opher Doron stands in front of the Beresheet space probe during a presentation by Israeli non-profit organization SpaceIL and the Israeli public company IAI, in Yehud, east of Tel Aviv. (Credit: Jack Guez/AFP)

What you describe as a deep flaw in the Israeli space ecosystem is generally cited as one of Israel's greatest strengths, namely the willingness to challenge the practices accepted and to take risks.

Look, if Iron Dome had evolved in the United States, it would still be on the drawing board. But that kind of culture doesn't necessarily work when it comes to space. Once you launch it should work. There are no second chances. This is not a drone that breaks down, you learn, you fix and you try again.

I learned a lot from my time in Israel. I was divorced when I moved there and met my new wife in Jerusalem. She was from northern California. I made many friends and had many moving and meaningful experiences in Israel. These five years have therefore been extraordinary. But it was very frustrating professionally, in the sense that I think I could have been much more helpful in advancing the Israeli space program.

Someone said to me, “If you had moved to Israel earlier and served in the military…” – the management teams, for the most part, had served together and I didn't benefited from this cultural experience.

I have since met other Anglos who moved to Israel when they were over 50. The management culture in Israel struggles to integrate seniors who come from outside, to give them a seat at the table, to listen to what they have to say and to be ready to change course.

Former NASA engineer Michael Kaplan under a model of the aircraft-mounted SOFIA telescope he helped develop. (Courtesy)

I think if the teams had listened, Beresheet could have been a success. The project would probably have won the X Prize. We wouldn't have wasted so much time. For three years, we were “three months away from the PDR [Preliminary Design Review, an important first step in the life cycle of a project]”. There is this bravado, which is wonderful, but you also have to accept the limits and be ready to bring in people from outside who really know the field.

It's not just in aerospace. I saw it in medicine. Experienced doctors come to Israel and are integrated at the bottom of the ladder, when they should be heads of departments.

I was talking to someone from Nefesh BeNefesh. I suggested they do a serious study of people who come in with high-level expertise and develop a program to get them into positions where they can be useful.

I am not sure that I would have made aliyah if I had known that I would encounter these obstacles. I ended up finding myself doing a lot of space consulting in Europe and the United States and wondering why I was living in Israel. That's when I figured I might as well go home, because my ability to help here sucked.

The Hubble Space Telescope, left, orbiting Earth and an illustration of the James Webb Space Telescope, right. (Credit: NASA via AP)

Could your experience in Israeli space teach you that space is inherently a game of superpowers, that it takes the scale and budget of NASA to do anything? something significant in space?

The future is commercial. Between the time I returned from Israel [in 2015] and today, two things have changed profoundly in space. One is the reduction in launch costs that started with SpaceX and the Falcon 9 rocket. It used to be that to get something into space you used Atlas and Delta rockets, and they cost $150 million to $200 million. per launch, and now we're at $50-60 million, a fourfold reduction because the rocket is reusable.

Elon Musk correctly applied an agile development process to aerospace. Israel knows all this; this is how the Israelis develop software. We don't build the whole product and then test it, we build a little and test it, then we rebuild it, then we test it, with teams working in parallel and integrating as we go along.

The other thing Musk did is design engines that wouldn't perform at their maximum capacity. If you want to make something reusable, you can't overstretch it. It should be running at about 75% capacity. It was a huge success.

I remember sitting in the cafeteria at Boeing with a bunch of Delta engineers when Falcon 1 suffered its second launch failure [in March 2007], and they were like, 'He's not gonna make it. Never. Hell, they were wrong.

The Amos-6, the largest satellite ever built by Israel, and the SpaceX Falcon 9 rocket on which it was perched, burst into flames after the rocket exploded on the launch pad at Cape Canaveral in Florida, on September 1, 2016. (YouTube screenshot)

The other thing that happened was this small electronics revolution brought about by smartphones. This transformed small cubesats, which were toys that universities used to train engineers, into satellites for communications, weather and remote sensing. During a recent mission to Mars, two small satellites called MarCO demonstrated that such a thing was possible. They served as relays.

I know that planetary missions are under consideration: a main mission will be put into orbit and several small cubesats will be sent as probes to explore the upper atmosphere of the planet. If they burn, that's okay, but in the meantime, they're getting data you couldn't get otherwise. These types of missions would not have been possible without the maturation of much of the cubesat technology. It has gone from being a toy to being a real solution.

These two changes mean that deals that weren't before are now being done in space. And it attracted huge amounts of investment capital. The rapid growth of the space economy will also help space science.

NASA will abandon the International Space Station at the end of this decade. It will be replaced by commercial habitats. It is not difficult to imagine that one of these habitats could be designed as an integration, test and assembly facility for future astrophysical observatories. Space tugs are already being developed in the private sector. Much of the infrastructure needed to build Webb's suites will already be in place.

All this infusion of private capital is helping to develop infrastructure in space. NASA and other space agencies will not have to pay for the development of these capabilities. Now suddenly NASA can pay for the use of capabilities.

It's very possible that by the time we start thinking about the next big flagship mission after James Webb, robotics will already be key. The powerful telescopes of the future could be 15 or 20 meter telescopes, and I believe they will be assembled and tested in space by a combination of robots and astronauts.

Illustrative: SpaceX's Crew Dragon capsule approaches the International Space Station for docking, April 24, 2021. (Credit: NASA via AP)

The lack of robotic serviceability is one of my deepest regrets about Webb. One of the boundary conditions we were given when planning Webb was, "Don't make it fixable." The reason was the cost. Hubble would have been a colossal failure if it hadn't been usable. But for it to be usable by humans, Hubble needed to be “human-friendly,” which is expensive. For example, there are no sharp edges on anything, because you don't want anything that can tear a spacesuit and inadvertently kill a person while working on it.

But what I didn't know at the time was that DARPA [Defense Advanced Research Projects Agency] was working on a robotic service concept called Orbital Express. It was built by Boeing. I then worked with the Boeing team on this project, to finalize it. If I had known at the time, I would have insisted on having a robotic maintenance option for the telescope, because the only thing that limits James Webb's lifespan is fuel. It will eventually run out of fuel to maintain station at L2 level.

So to end where we started – as things stand, Webb is not fixable at all? Even if we could bring a robot there, the machinery needed for maintenance is not structurally in the right place? So once there's no more fuel, it's over?

I think it's true. That said, there are a lot of things that we ended up doing with Hubble [which was originally supposed to go out of business in 2005] that were supposed to be impossible, things that we maintained that weren't designed to be maintained, but which extended its lifespan.

In this Dec. 21, 2015, photo provided by NASA, Expedition 46 Commander Scott Kelly participates in a spacewalk outside the International Space Station, during which he and flight engineer Tim Kopra, not pictured, moved the station's mobile transporter wagon before docking with a Russian resupply spacecraft. (Credit: NASA via AP)

The next big leap for me is thinking about how to take advantage of emerging space infrastructure, things like Starship [SpaceX's planned interplanetary rocket] or the New Blue Origin's Glenn, which doubles or even triples the size of the fairing, allowing large modules and very large mirrors to be thrown. These are game-changing elements.

Or maybe we could link astronauts in a habitat in low Earth orbit to an orbital transfer vehicle to go to L2.

There are all kinds of architectural paradigms that we can consider to take advantage of where we are today and where we are headed that would constitute paradigm shifts.

Space has a bright future.