How would NISAR expand our understanding of the Earth? | In Focus podcast

0:00 Hello and welcome to this episode of In Focus the Hindus podcast series and lately a video series as well where we discuss news that has animated public discourse. I'm Kunal Shankar. On July 30th, India and the United States marked a historic milestone in space collaboration with the successful launch of NISAR, the NASA ISRO synthetic aperture radar satellite. This flagship Earth observation mission jointly developed by the two space agencies is the first satellite to use dual frequency radar NASA's Lband and ISRO Sband to continuously monitor the Earth's surface. NISAR is expected to

0:45 deliver breakthrough data on land deformation, glacia, dynamic forest, biomass, and natural hazards such as earthquakes and floods with high resolution all-weather dayight imaging capabilities. The mission is poised to significantly improve climate resilience, agriculture, monitoring, and disaster response. Beyond its scientific value, NISA could also unlock new commercial opportunities powering geospatial analytics, data services, and early warning systems across industries from insurance and infrastructure to agriculture. To discuss this scientific milestone and what this means to global space cooperation, we are joined by Dr. Karen St. Germaine. Dr. St. Germaine is

1:30 the director of the earth science division at NASA's science mission directorate where she oversees NASA's full earth science portfolio satellite missions technology applied research and data to action programs. Karen, thank you so much for joining us today. So can you give us a few examples of scientific studies that are possible with NSAR but haven't been possible so far with the existing crop of Earth observation satellites? >> Absolutely and it's great to be with you. Um, nice. The way to think about nicar is that it will see any anything that has structure to it that moves that changes its position at a scale of uh less than a centimeter um over o over an area about the half of a tennis court.

2:18 So 10 foot say square. Um, so that means when I say anything that has structure, it could be forest, it could be buildings, it could be glaciers, mountains, land. So anything that moves, we'll see at an unprecedented level of fidelity. And what that means is we will be able to see the slight bulging that happens before a volcano erupts. uh we'll be able to see um the lands uh land becoming unstable before a landslide. We'll be able to see building shifts after an earthquake or or any other sort of event. So, anything that moves, a forest that gets cut down, we'll be able to see that. So, anything that changes, we'll be able to see. And

3:05 that's an extraordinary new capability for us. >> Okay, great. And um you know after the launch NISAR will start its 90-day uh commissioning phase and this is the world's first dualband um Satellite. In this phase uh do you foresee any challenges with calibration especially with crossband calibration and could you break down that process for us? Yeah, the so uh there are a number of different aspects to the calibration and uh and largely the ISRO team will focus on calibrating the S-band radar and the NASA team will focus on calibrating the L-band radar. They don't really get crosscalibrated, but each one will look at its own special targets. Now, what do

3:51 I mean by a target? It's something we call a corner reflector, and it is exactly what it sounds like. It's a corner just like the corner of a room >> and it has a special feature which is that when a pulse of energy hits it from any direction it reflects back in exactly the same direction. So we use these targets uh to to calibrate independently each of the uh instruments. And then the only other thing we really have to pay special attention to is the alignment the pointing. Are they pointing in the same place on the ground? And for that we'll use uh we'll use the data itself. So the data itself will uh identify features and we'll align those those features I see from each from each radar.

4:37 >> Okay, >> great. >> So NASA's investment in NAR is about $1.2 billion, right? >> That's about right. >> So if possible, could you tell us how this cost breaks down on the US side? Well, the uh the way NASA builds missions, we establish a life cycle cost. So that uh that life cycle in it starts when we start designing and it runs through the design phase, the the build, the integration, the launch and all the way through the uh what we call the prime mission which for NISAR is the first three years for NISAR that included uh the deployable antenna. It's

5:23 the most distinguishing feature of of NISAR. It includes the L-band radar and of course the Lband and the Sband are operating through the same reflector and then uh of course uh there are various electronics and data handling uh elements as well. So um uh and then there are the people right the the people that that put it all together and and worked so closely with the team from India. So even after we were finished building our part, our team came to uh to India to work with ISRO to integrate it onto the spacecraft and prepare for launch and even sat on console uh for for the launch. So it's uh it's a it's a total cost. Um and you know speaking of

6:10 costs and and uh there there's a lot of interest about the commercial aspect uh the applications aspect of MSR and u could you just tell us a bit about the kind of uh interest that it has generated uh >> yeah and actually let me let me take a step back and talk about earth observation data in general because in general understanding uh the the earth it's you know the surface the atmosphere here. Um, and the change that changes large and small that can have impact on communities and businesses, uh, that's become an enormous area of interest. In in fact, um, NASA's been collecting data on the Earth system for, uh, more than

6:58 60 years now, right? And uh and we find that about threearters of our Fortune 100 companies are drawing some something out of that earth observation archive. Um and we also find that about 75% of our users and we have more than 5 million users about 75% of those are coming from right >> addresses. So we are talking about agriculture producers um and uh the insurance industry, the finance industry, the transportation industry um and that's before you even get to things like disaster response, >> right? >> So we have a tremendous interest in general >> for NICAR specifically. We know that NISAR will produce data that uh can

7:44 directly benefit agriculture. Yeah. Um and then also risk assessment. Everything from natural hazards like I mentioned earthquakes and volcanoes uh which are both issues in the US but also things like wildfire risk because NISAR will be able to characterize how much fuel >> is in our in our wildlands. So that's uh dry fuel that is uh burnable. So um so there are all these application areas. Um, and one of the things that we do that we're really excited about is anytime we launch a new mission, we uh we have an early adopters program. These are people out there who anticipate what NISAR might do for them in their

8:29 business. And they don't actually we don't require that they tell us a lot about what they intend to do. But right now for NISAR, we have I think it's at least 200 of these early adopters. And once the data start to roll out and the excitement builds, >> yeah, >> uh we expect it to take off from there, >> which you believe is a high number, the early adopters. Yeah, >> it's a high number for uh for a mission that is um that is as sophisticated as this. Um and what I what do I mean by that? What I mean by that is um pictures are generally easy for people to use. synthetic aperture radar data requires some pretty complex processing to turn it into usable information, >> right? >> But all the data is free and openly

9:15 available um from us. Uh we will distribute it out of the Alaska SAR facility. Mhm. >> Um and then uh that will be the LBAN data. Uh and uh our colleagues at Israel, they they will they have their own distribution mechanism for the SBAN data, but it will also be open and freely available >> available. Right. >> Okay. Speaking of big numbers, >> uh also can you explain why NISA took 11 years to build? Were there any particular uh particularly difficult engineering challenges that you had to overcome first? >> Yeah, absolutely. Um you know, first it's an enormously complex system. with uh many dozens of subasssemblies and and uh that had to be designed and of course uh to make these two radars work together and operate through a single

10:00 reflector uh there's a lot of design work that had to happen up front. Um so it was challenging to begin with and then we had a couple of other uh particular challenges. one uh and this one happened right as I was starting my job >> um was uh co hit. >> So think about uh an integrated engineering team already separated by time zones and distance and now uh having to work through a a global pandemic >> well also in person. A lot of this work had to happen in person. So we had people who had to travel at the height of COVID uh had to leave their families right

10:47 >> um and remember that the waves of CO hit differently in the US in India. >> That's right. >> So we had people uh on both teams uh sometimes uh come down with CO. >> Yeah. >> When they were in the opposite country and so we had to take care of one another's teams. Right. >> Um and then we had to develop entirely new protocols >> for how people could work together in a space uh and remain healthy. >> So so that was a big one. And then more recently we uh the this reflector is an enormous uh it's a 40 foot about a 40 foot >> deployable reflector. And uh and when we were in India integrating and we were testing in thermal vacuum, we saw some

11:32 data that worried us. >> Uhhuh. >> And uh we were really afraid that uh there may be too much of a thermal load on that reflector before it gets deployed, >> right? >> And uh and it might overheat. And if it did that, it could uh challenge the structural integrity. And of course, when you've got a deployable antenna, if it doesn't stay taut, >> it doesn't reflect the way you want it to. So, we ended up uh demating that reflector, bringing it back home, um applying a reflective coating so the sun couldn't cause it to overheat on the struts, not on the reflector surface itself. And uh and then we had to ship it back and reintegrate. So we we had a

12:18 couple of technical challenges which we expect when you're doing something as difficult as this >> right collaborative. Speaking of challenges, uh what do you think are the limitations uh in in terms of um penetration depth of the L band versus the Sband? >> I I don't I think I would not frame it so much in terms of limitations as I would frame it that they are both specialists and they just have different specialties. So the L band has a longer wavelength and uh and that means it can penetrate deeper. So it can penetrate through foliage. And of course they'll both be able to create imagery in day and night through clouds and weather. It's just that when there is some uh

13:04 some material there like foliage, the Lband will penetrate further. It will interact with larger structures. the Sband uh will give you more information about that foliage because it's more sensitive to it. >> So that's just one example. So they they will really just see different things >> and the power then will be when we combine the information from them and get a more >> holistic holistic view. Right. >> Right. Right. Right. >> Exactly. >> This is kind of a followup to that. Uh both the Lband and the SBAN radars use the same reflector since Sband has a shorter wavelength than the Lband. uh does this create any trade-offs in either LBand or Sband performance? >> It doesn't. And the reason for that is because this is a synthetic aperture

13:54 radar. So, it uh creates its spatial resolution um as it moves along. Each radar is taking snapshots as it moves along, you know, to get this kind of centimeter level fidelity and uh the kind of spatial resolution we're achieving. If you were to use a uh a solid antenna, it would be miles long, >> right? >> Um just like when you're talking about a camera, if you want to be able to get high fidelity, you need a big lens. Same idea, but we can't deploy an antenna that big. So what we do, this is still a pretty big antenna, but what we do is we uh we build up image after image after

14:39 image um to get that that resolution. And uh because of this technique, it's actually independent of wavelength. >> So it works the same for S and for L. So again, the only thing that's a little different is uh because the the feeds the antenna feeds for the Lband and the Sband, they can't physically occupy the same space. So they have to be next to each other. And that means there's a slight difference in the way they uh the way their pulses reflect off the antenna. Okay. >> And and come back. So that's that positioning difference. Okay. >> That we can correct for. >> Uh could you uh tell us a little bit more about that slight difference? >> It's uh Yeah. So um so the way a reflector works the f you you would ideally want to put the feed at the

15:26 focal point of the reflector uh but when you have two feeds you can't uh you can't do that. So they're slightly offset so that means they illuminate the reflector just slightly differently >> and uh and so the alignment is just a little bit different. the team optimized uh the design to uh to minimize that difference and to make it so that they could correct it in post-processing. >> Okay. >> All right. Um and um you know how do NASA and JPL's radar systems uh for planetary exploration feed into and evolve from their Earth observation um systems? And even at the moon, NASA and ISRO um have been collaborating specifically using radar systems of DFS

16:13 on Chandrean 2 uh orbiter and the mini RF on um LRO. Can we imagine an ISAR built for missions to the moon or Mars or beyond? Yeah, it's a it's a great question and of course um once you have expertise in a technology you can use it in many many ways and this is often the case in NASA between earth science and planetary science. Uh one uh one of us will develop a new technology or advance a new technology and then it can be used very broadly. So uh so absolutely and we love that kind of interplay. I love seeing earth science technologies make it into planetary missions. Um so that's one one aspect. The other thing is what

17:02 we learn from NISAR on Earth can inform what we understand about other planets. >> Uh so so there are lots of ways that we interact across the disciplines. >> Could you give us an example of a a lesson that you would learn from NASA that would help with the planetary mission? >> Well, um let's see. Uh certainly uh one of the things that uh NISAR is is going to tell us about is what's going on underneath the crust of the earth underneath the surface >> because we'll be able to see uh these very small motions that you and I don't experience daily right we can't sense these uh but NISAR will um and it will allow us to advance our models about how

17:49 the interior Earth planets work. >> Okay. >> And uh and those kinds of models are the same models we use when we try to understand how a planet like Mars works. Um so yeah >> I see right yeah so as you said it could be interchangeably used planetary missions as well as >> so NASA is a first of its kind equal partnership between NASA and ISRO. Can you tell us what kind of precedented this collaboration sets for future major collaborations or technology sharing between the two organizations? First I will say I have been singularly focused on getting NISAR off the ground um and and not really looking beyond um of course uh you know when I when I uh was preparing for launch one of the things

18:36 that I did was uh I found not found I went and and uh and bought a little figure of >> Ganesha >> because my understanding is Ganesha brings um brings uh uh good uh good tidings for the beginning of an enterprise >> and so as for as long as we've been working on NISAR really the launch represents the beginning of that collaboration we will be working together closely uh for many years just to extract all the value out of NISAR um but as as you said NASA and ISRO are working together in many ways in human exploration. That's right.

19:21 >> Um and uh and potentially in other areas. So um I think I hope uh and I think that we will have a rich collaboration for a very long time and I think it will span the areas of interest from um earth science to planetary science and human exploration. >> And that's it from us. Thank you for watching and for more such videos do follow the Hindus YouTube channel and follow us on your various social media platforms.