[00:00:01] Speaker A: So right there would have been the star and it's super bright and it's, everything else is blinded. Now coronagraph, you turn it on and all that light is thrown out of the field and you can see the planet.
And that's very special, super tricky.
Like you have to get everything just right so you can do it.
And that's what, you know, we spent a decade at JPL developing to, to be, to be able to do that. And, and it, in all of its tests, it did extremely well. We went through lots and lots of reviews. And so now we have high hopes that it'll do in space what it did in the lab.
ID the Future, a podcast about evolution and intelligent design.
[00:00:45] Speaker B: So a new space telescope was recently launched by NASA. What's it going to look for? Why do we need another telescope exploring the heavens? And how does an intelligent design perspective enrich both the expectations and the interpretations of that telescope's findings? Welcome to Idea of the Future. I'm your host, Andrew McDermott, and today I am welcoming and delighted to begin a two part conversation with Dr. Bijan Nemady about his work on the Nancy Roman Space Telescope.
He's also going to help us understand the goals of the new observatory and how it's going to contribute to humanity's understanding of the cosmos. Dr. Namadi is a physicist and expert in astronomical instrumentation who spent many years at NASA's Jet Propulsion Laboratory. He played a key role in developing the Coronagraph instrument aboard NASA's Roman Space Telescope. He holds a PhD in high energy Physics from the University of Washington and is the founder of Telus One Scientific. He's also written and spoken extensively about exoplanets, planetary habitability, and the scientific case for Intelligent Design.
Dr. Nimati, welcome to ID the Future.
[00:01:58] Speaker A: Good to be with you, Andrew.
[00:02:00] Speaker B: Now, Bijan, you spent roughly a decade helping to develop technology aboard the Nancy Grace Roman Space Telescope and you were actually invited to attend its launch.
So tell us, what was that experience like and what was going through your mind during that final countdown to get it into space?
[00:02:17] Speaker A: Well, it was a lot of satisfaction because, you know, I and many of my colleagues, we've worked about 13 years to get to this point. And so when I started in this field, I had worked for about 13 years on a different mission called the Space Interferometry mission.
And after 13 years it was canceled and it was sort of a budgetary constraints in those years and so we started over on a different mission. So on the second round of 13 years spent on a mission, it Was great to see finally the thing on the launch pad and taking off.
It was a great thrill.
[00:03:00] Speaker B: Yeah, that must have been quite something seeing it. Now tell us, where is Roman headed and how long is it going to take to get there? Maybe it's there already. I don't know the latest, latest information, but what needs to happen before it can begin conducting observations and capturing data?
[00:03:15] Speaker A: Yeah, so Roman's headed to a special orbit called the L2.
It's not there yet.
It's going to take it some months, like two or three months to get there, another couple of months.
And at L2, this is called the second Lagrange point, named after Lagrange the mathematician, but it actually was discovered by a mathematician from the 18th century by the name of Leonhard Euler.
And Euler discovered, and he was, interestingly, he was a devout Christian, by the way, and he was a polymath. He's just like an amazing guy. His name is all over all kinds of mathematical and physics related things.
Anyway, Euler discovered that there are certain orbits that have the characteristic where normally in an orbit, as you go farther from the massive object that you're orbiting, your angular velocity drops and you're going slower and slower as you go farther out.
And so if the Earth is a particular distance from the sun and it's orbiting the sun and it takes 365 days a year to get around it, if you go farther from the Earth, farther from the sun than the Earth is, then your orbit is going to be a slower orbit in terms of days per revolution.
So normally what happens is that if you go farther out from the sun, then you will fall behind, as it were, behind the Earth. But Euler realized that there's these special places where the gravity of the Earth adds to the gravity of the sun and that allows an object to actually be at a particular distance. It can have an orbital angular speed that matches the Earth's. And so here's the sun, there's the earth, and at L2 you're kind of tracking exactly in an angular sense what the Earth does.
If you were being at that same distance, but not at L2, you will fall behind because you're not getting the help from the Earth's gravity anyways. Beautiful result. There is a L1, there's L2. L1 is the opposite on the other side of the Earth relative to the Sun. That orbit is about a million miles away, which is four times as far as the Moon. So the situation that we're going for is one in which the Earth, the Moon and the sun are all mostly look kind of like in a line or at least in a region of space.
And that's important because the instrument we're sending to space in Roman is sufficiently delicate. It's so precise in what it needs to do optically, and it's been made to do it, but thermal perturbations are a difficulty for it. In other words, you want it super pristine. That is one of the reasons we're sending it to L2. And at that, when you send it that far out, Earthshine and the heat from Earth shine doesn't become a problem.
And the variations of it don't. Don't become a problem. For example, when Hubble was sent first up, you know, Hubble was orbiting is the. Orbiting the Earth. And there would be these eclipse events where the Hubble would be on the other side of the Earth, the Earth relative to the Sun.
And as it would come from, you know, one side of that eclipse situation to the other, the solar panels would be almost like hot cookie sheets coming out of the oven. Go bang. And it would just like rattle the whole thing. And I think they fixed that. But. But it's very desired to be in an orbit like L2.
[00:07:06] Speaker B: Okay.
And that. Is that where James Webb's hanging out then?
[00:07:10] Speaker A: That's where James Webb. It's expensive real estate, but these telescopes are worth it.
[00:07:15] Speaker B: Yeah.
Now we have Hubble and we have James Webb. So why did NASA want another space telescope in operation? What's it going to do that these others can't? Or maybe it's helping them.
[00:07:28] Speaker A: Well, first of all, you know, Hubble worked, has worked magnificently after its famous repair.
It had a funny story at the beginning, which, you know, is another story, but it's been very productive.
But Hubble is a general purpose great telescope. It was how we started and how we, you know, learned to do space telescopes, at least on the NASA side of things.
But James Webb is.
What is remarkable about James Webb is that James Webb is a 6 meter aperture. And aperture sizes. That's basically the size of the biggest. Usually the first collecting aperture that, you know, it refers to the first collecting aperture that collects the light.
Not only are you collecting more light, which is important, but more importantly, you are collecting it across a wide amount of area.
And that affects the ability of the instrument to resolve fine features in the field of view.
And it goes to a phenomenon having to do with the wave nature of light. If light was just rays, this would not be an issue.
But because light is actually Waves.
A phenomenon called diffraction limits how fine a structure you can see on the sky in an angular sense. So imagine you're looking at a binary star. That means two stars nearby, let's say.
To most of our eyes, we think that's one star. You put it in a telescope with a bigger aperture, you see it's altar two.
What has happened is that blur has been removed by the fact that you can resolve better to get the better resolution. You need aperture, and there's no way getting around it.
And very expensive to put a wide aperture, a big aperture out there. And James Webb is that. But James Webb is a lot more. James Webb is a fantastic infrared instrument that can make very precision, you know, types of studies in a sort of a narrow field sense, meaning it doesn't look at wide swaths of the sky. It just looks in very narrow parts of the sky. But what it does, it does with tremendous power. Nothing else like it. So it kind of covers a niche that cannot be right now replaced.
Roman is complementary.
Instead of a narrow field, it actually has a colossal field.
Its field is 100 times that of Hubble. And it can, you know, at one, in one shot, see a scene that is that much bigger.
And there are some transient, many transient phenomena that are interesting, both in the areas, let's say, of exoplanets or in the areas associated with dark energy studies where you want to see these transient events.
And if your transient events, you have to get lucky to see them. Having 100 times the angular area means you have 100 times more opportunity essentially, to see these transient events. So rowing can do things like see a transient event, hand off to Webb, and Webb can make a detailed study that, you know, so they can work together just beautifully that way. Okay, but besides this field of view thing, Roman has a special other instrument called a coronagraph, which actually is narrow field, so doesn't have a field advantage, but it has the ability to directly detect planets. And that's a very special device. And we can go into that later. But, yeah, those are the things that Roman does.
[00:11:26] Speaker B: Okay, and your work on Roman focused on the coronagraph instrument. Can you describe what it is and what you did to help develop it?
[00:11:36] Speaker A: Yeah, so I mentioned the wave nature of light. I mentioned that the resolution, you know, is a fundamental thing.
If you imagine looking at our solar system from, let's say, 10 parsecs away, and so 20, 30 light light years away, what do you see? You will see our sun as a star. And then would you see our planets?
Well, it Turns out that because of that phenomenon of diffraction, let's say that you had the Roman telescope, but you're an alien civilization looking down at us. What do you see? You see a spot, and that's the star. That's our sun.
And then there are the planets. The planets are much dimmer than the star.
The brightest of the planets that you would have a chance to see would have been our Jupiter.
Jupiter is about a billion times dimmer than the sun in reflected light.
The earth is 10 billion times dimmer than the sun in reflected light.
Now, depending on the aperture size of your telescope, you know, it's not exactly fair to say the 10 billion and the billion because they're not on top of each other after all. I mean, the image of the planet and the star, they're separated and the star's brightness is tapering off. Yeah. So in a sense, I exaggerated.
The moon is only 40,000 times, you know, swamped by the star.
I mean, the Jupiter, I'm sorry, Jupiter is 40,000, and the Earth is about 40 million times.
But so, you know, if you think about a needle in a haystack or, you know, sort of signal to noise, your signal is 1/40,000, you know, where Jupiter is and about 1/40,000,000th where the.
The Earth would be.
[00:13:39] Speaker B: Wow.
[00:13:40] Speaker A: So directly seeing the light from an exoplanet, directly seeing that planet light, you're gonna have to first dig out a factor of, even for Jupiter, something like 40,000 deep, the starlight, to see the planet light.
So the chronograph, what it does is that it manipulates the wave properties of the light that it has received and scatters the starlight, the sunlight, the starlight, the host star's light away, creating a dark zone, or sometimes we call it a dark hole.
And so right there would have been the star. And it's super bright, and it's. Everything else is blinded. Now coronagraph, you turn it on, and poof, all that light is thrown out of the field and you can see the planet.
And that's very special, super tricky. Like, you have to get everything just right so you can do it.
And that's what, you know, we spent a decade at JPL developing to be able to do that. And in all of its tests, it did extremely well. We went through lots and lots of reviews. And so now we have high hopes that it'll do in space what it did in the lab. So.
[00:14:58] Speaker B: Wow. And the other telescopes don't have a chronograph instrument.
[00:15:04] Speaker A: Well, you know, to that's a really good question. There are coronagraphs and there are coronagraphs. Yeah. So when a typical chronograph design, normally you might just imagine, like just throw everything away. Just say you have a lens, you have a plate, you focus light. There's a star, you see a spot, that's your star.
A coronagraph says, before you do that, let's put a little disk there and actually block out the star and then get that light, the rest of the light to go out and use another lens and focus it again.
When you do that, you actually get rid of a lot of the star, like 99% of the star. But 99%, that means only a factor of 100. So what happened to my factor of, let's say a billion?
Yeah, that's where additional technology is needed. In other words, occulting and various masks are needed. But on top of that, we use special deformable mirrors that will just put the right kinds of wiggles into the. To the light that's coming the wayfront so that interacting with the masks, it does this magic and it vanishes in the area that you need to. And it's all manipulating light, as in its wave nature. A lot of these designs first start with math. You just work out the equations. If your wave looked like that, would it would a lens focus it and be able to throw that light out. Once the math works, then you go and say, well, gee, can I make that happen?
So that's where you use deformable mirror, active optics, you know, fancy masks, special materials. And you spend years and years in the lab trying to make that a reality. And that's where, you know, the corona gap. So in long story short, there are coronagraphs, but some of them amount to just like something occulting that first spot. But not no deformable mirror, no fancy phase masks, no nothing. So they can do a factor of maybe a hundred, maybe a thousand.
But if you want a factor of tens of thousands or millions or a billion, that's a whole. There's nothing else that does this at the level of Roman. Yeah.
[00:17:15] Speaker B: Okay, so Roman's got a very special, very advanced coronagraph instrument.
And it's going to. It's going to let us see what's behind these very bright stars. Now, help us understand what an exoplanet is. And is Roman going to help with the study in search of those?
[00:17:32] Speaker A: Yes. An exoplanet is just extrasolar planet, meaning it's a planet around a star that is not our sun. So that would be any of the stars in the sky, you can ask the question, does that have planetary companions?
And so that's an exoplanet. Roman is going to study and search for exoplanets in multiple ways. Roman has two instruments. There's a wide field instrument and the chronograph. The wide field is actually going to make in some ways, arguably the biggest in statistical sense, the biggest impact.
The Roman Wide field is going to use the famous transit technique that was demonstrated spectacularly by the Kepler mission and now it being used on ground based telescopes everywhere. It's a wonderful technique. It's basically you are doing precision photometry, in other words, measuring the brightness of a star's light.
You're, you're measuring that and you're monitoring, you're monitoring, you're monitoring and suddenly you see by a part in 10,000, it got dimmer. I mean, you know, just almost imperceptible. So you have to have very good precision, what we call photometry, you know, measuring light.
But if you do that and imagine you look at a crowded field and you just. Stars everywhere and you just stare, you stare, you stare, stare over weeks and occasionally you see, you know, if you make very precise measurement, you see the light level drop, you've seen a transit, you've seen a companion go in front of the star.
And so that technique obviously is statistical. There are certain things that have to happen. For example, if this is your star and the orbit of the planet and you, the camera are the viewer, the telescope. Well, if that orbit is like this, occasionally you'll see a transit. What if the orbit is like this and it's going in this circle? Well, you'll never see a transit. So it's statistical.
Some stars may have planets. You just won't see it because you have no efficiency.
So it's a statistical approach. You look at thousands of millions of stars and you then catalog which ones you saw the transits. And what kinds of transits did you see? Consistent with two planets, you know, boom, boom, with different periods, all of that. So anyway, the wide field instrument, because it has this giant field of view, can just look at this massive swath of stars, let's say in the galactic bulge or somewhere else. And it's just going to stare and try to survey and look for transits. There's another technique called gravitational microlensing that's really weird.
You are looking for the existence of a planet because it's by using the fact that it just so happens that its parent star is in front of a background star from your point of View such that it gravitationally is bending that light of the background star and magnifying it. So you actually.
And the stars are all moving in space. So from your point of view, suddenly you see light go up and that is actually the background star being gravitationally lensed to your instrument.
And then if there's a planet suddenly goes, you see a little spike as well. And that, that little, there's a fancy word for it which I can't remember, but that, that little spike is essentially the signature.
Again, it's statistical. You have to get lucky. So you look at very large samples. So we've discussed transits and gravitational microlensing. The third one would be direct imaging. You look at a star and you said you got planets and that one is the coronagraph. The coronagraph just directly can query that particular star and see it. It's much harder, the yield is much lower. It's very difficult to do. So you kind of use the other techniques to pick your prime targets.
And then you don't waste time on non prime cameras because it's going to be expensive time wise. And in space, by the way, with space telescopes, expensive means time. Time is what is running out. And so you, you really care for time, huh?
[00:22:00] Speaker B: Now will we get pictures from Roman or is it mostly going to be sending data that scientists will parse out and put together?
[00:22:08] Speaker A: Oh, it's going to have gorgeous pictures coming out. Yeah, it's going to be beautiful pictures. Yeah, yeah. Because you're going to have these wide field, super wide field, infrared pictures. There'll be false color, but it will be. The color means something.
It's really a spectral information. It's just, it's in the infrared and it's a super wide field. So I think we're going to be in for a treat with pictures from.
And coronagraph images are going to be cool, super cool to see planetary systems, you know, and you know how the planets are organized and.
[00:22:46] Speaker B: Sure. And it's just a little. Aside from that. I was telling my kids about the Roman telescope going up and they were wondering how data gets sent back from these telescopes that are so far away.
What technology is used there?
[00:23:00] Speaker A: Just very briefly, very briefly, it's radio signals from.
There is an antenna on the telescope. In fact, the last picture we have of Roman, if you like look on YouTube when it was finally jettisoned from the final stage and you can see it going away. You see it right in the foreground is the big antenna is on the bottom of it and that's what you see and so there are deep space network, there's radio telescopes in various places on Earth, and there's handoffs because the Earth is rotating as the thing's going. So there'll be, you know, one in Australia, there's going to be, you know, some elsewhere on the, you know, in the northern North America. And so there's these handoffs and radio signals.
[00:23:47] Speaker B: Okay.
[00:23:48] Speaker A: The future of all this is going to probably go to laser communication. And that's a technical reason. But I think that, you know, at some point in the next, next space telescope or the one after it was going to be laser common instead of radio.
[00:24:03] Speaker B: Very interesting. Now, getting back to the work that you did briefly, you played a major role in selecting the detector for the coronagraph instrument. And apparently the detector for the coronagraph has to be very special. Can you tell us something about the detector's significance to the mission?
[00:24:19] Speaker A: Yeah, yeah, it is really demanding. So when I first got started with Roman, they said they're looking for a detector person.
And I was like interviewing, you know, I was at jpl, but it was like I was going to be interviewing with a group that's going to do detectors and with this project.
So, so I got the job, you know, I got the assignment.
And, and then the first thing I had to do is to essentially figure out what would be the yield in terms of the number of exoplanets we would be able to discover versus the properties of the detector. And at that time, there was a number of technologies, some of them super fancy, you know, cool to the like, nearly absolute zero.
All kinds of fancy technologies. There were lots of great technologies, higher technologies than what we used.
But you see, when you do a space mission, you can't use the latest, coolest thing necessarily because the readiness of that thing as a technology is low. And so it's going to break on you and just blind the whole experiment, the mission. So there's a compromise. You don't want to get something very conservative that just doesn't perform and you don't want to get the hot off the press latest technology that is so clunky right now that you jeopardize the mission. So where's the near the curve? Where's the best technology?
And that was what I was. Basically my first job was to figure that out.
And so we settled on something that was well proven in medical imaging called an electron multiplication CCD or emccd, which is what Roman now has. That was what I helped select. And I did it by putting the parameters of these various detectors into a model that I made and said, look, time is expensive in space. You have so much time, how many planets can you search? And if you use this detector, it's going to take you. You won't even have time to do more than so many. If you use this kind, you know, you could do a lot. But the side question is this detector is still not real. It's. It's just in the lab, and it's not going to be seriously ready. And so the sweet spot is this emccd, which can detect single electrons, basically photoelectrons. And so we call that photon counting. In other words, when light comes in each individual photon, you can essentially count it.
So just to give you an idea of how dim we're talking about, imagine you, you got some man holding a candle about 10 miles away on a, maybe a little hill. If he's not on a hill, you won't see him because of the curvature of the Earth, but he's 10 miles away.
Every one of your, each one of your eyes gets about 1200 photons per second out of that candle from 10 miles away.
1200, a thousand photons every second, but it's still. Just think that's a candle from 10 miles. Think of how dim that is. Well, if Roman tries to look for a Jupiter instead of 1200 photons per second, it's going to get something like one photon every hundred seconds.
So you wait 100 seconds, you get a photon, and you don't want a detector that misses it or has too much noise or isn't efficient. And that's how demanding the detector. That's the kind of detector that's on Rome. It is a very impressive kind of detector.
[00:27:57] Speaker B: That's a good analogy to help us understand, too.
Now, just briefly as we wrap up, I know you must have faced technical risks and hurdles as you did the work on Roman.
Does one thing stand out as something that you really had to overcome in order to make this mission successful?
[00:28:18] Speaker A: Well, the systems need to work. All the nuts and bolts that we put in that thing, the deformable mirrors, this fast steering mirror, the focus mechanism, the precision alignment mechanisms, the detector, of course, all of that has to work.
And beyond that, another thing that needs to work is that our assumptions about the stability of the telescope as the thermal conditions change, and it will change. In other words, the telescope's looking at a star, and it needs to take a, what we call a reference measurement at another star. And as it changes, it looks that way. The sun angle has changed just tiny bit different Heating it warps it just slightly, ever so slightly.
All of that's been modeled. All of that looks good. We now have to see it happen for reality. And if it does it all, then I think we have all the makings of a very, very powerful instrument there.
[00:29:17] Speaker B: Yeah.
Well, you've spoken previously on ID the Future about how the evidence for intelligent design changed your understanding of science. Does an ID perspective help shape the kinds of questions you ask as a physicist, or does it help you interpret evidence after the fact? Or a bit of both?
[00:29:35] Speaker A: Bit of both, actually.
I'll handle the kind of questions first.
From a design perspective. If I'm on the experimental side, which we who are planning, you know, building telescopes, we're on the experimental side, not on the theoretical side.
What are we looking for? We're looking for.
And from a design perspective, we know, like the ID filter starts with eliminating law, then eliminating chance.
And so you can, if I'm doing observational astronomy, I would like to take a shot at eliminating chance. That means I need to get good statistics. If I need to get good statistics, it means I need to have an instrument with great efficiency. Efficiency matters because imagine you say, well, I built this experiment and I would look for this effect and I didn't see it. And then I ask, well, how efficient were you? I mean, in other words, if it was there, would you have seen it?
Not really. I would have had a one in hundred chance to see it. I'd say, well, that, that's not very convincing. Your, your experiment was not very efficient and you didn't see it, so we're not surprised.
So what you want to do is convince everyone that your experiment was actually very powerful, very efficient. If it's there, I would have seen it and I didn't see it.
So from an ID perspective, we want an instrument, a space telescope that can do massive surveys just like Roman does, that gets tons of statistics because then your statements about the rareness and occurrence rates and habitability requirements, how many of those you can detect and how prevalent they are, those things mean something. We measure them, we have small error bars, and we see that they're low.
So in terms of the questions you ask, you go for those statistical questions and you try to get good small error bars on those in terms of interpretation.
I think that the paradigm that you use is going to affect your interpretation, and that is just unavoidable in science. And in fact, you know, you look at 20th century astrophysics and you think, you know, in 1915, Einstein comes up with general relativity, 1924 Hubble discovers, you know, the expansion of the universe, essentially, you know, and a finite time, you know, age of the universe. And immediately the scientific paradigm is, is shaken and, and much of the rest of 20th century gets spent trying to find a wiggle away out of a finite age of the universe. And so they, you know, there is no question that the way you interpret the data is affected very much by the paradigm in which you're working.
And so with, with regard to id, I think we would like to just, you know, look at the data from that point of view and say, from an ID point of view, would we expect this or would we not expect this? If we see rareness, do we expect rareness, do we not expect rareness? Or we would comment on the fact that from a materialist point of view, you know, what would should be an honest conclusion from what we see. So that, that's, those are the kinds of questions that we would, we want to engage in and, and prepare for.
[00:33:06] Speaker B: Yeah, that's great. I really like that summation of, of how an ID perspective can inform on both sides of something you're pursuing, both what the results are, interpreting it, but also how you move into that and seeking efficiency in data so that you can basically cover your bases and say, yes, I, I did what I could to answer this question. You know, that's really good.
Well, we're going to leave it there for today, but in a separate episode, we're going to talk more about the search for habitable planets, what it means for a planet to be habitable, and how Roman is going to help us, along with the Webb Space Telescope, to make some brand new planetary discoveries. We're going to see things we've never seen before and it's all very exciting. So we'll continue to look at all of that and how an ID perspective can inform all of that as well.
Makes for a very rich approach to science when you can ask questions.
So all that and more is coming, so stay tuned. And Dr. Namadi, I really appreciate your time today.
[00:34:16] Speaker A: Glad to be with you, Andrew. Thank you.
[00:34:18] Speaker B: Now to learn more about Dr. Namadi's work on space telescopes, you can visit his company website, tell us1.com and in the show notes for this episode, we'll also link to Dr. Nimani's profile at Discovery Institute's website, which will give you links to some relevant articles. And of course, you can kind of track the progress of Roman yourself. We'll be writing about
[email protected] I'm sure.
And it's going to be very exciting to see what happens. Well, until next time, I'm Andrew McDermott for ID the Future. Thanks for joining us.
[00:34:53] Speaker A: Visit us at idthefuture.com and intelligentdesign.org. this program is copyright Discovery Institute and recorded by its center for Science and Culture.
