So right here at Mount Strommloon, what's called the Advanced Instrumentation Technology Center, where we do all sorts of space things. And as we've explored already, we've talked a little bit about communications and laser communications, in fact, laser optical communications. And so today we're here with Francis Bennett, who is leading this effort at Mount Strommloon A&U to do something that seems straight out of science fiction. So thanks for joining us, Francis. No, all right, thank you. So what is it that you actually do? I know that's a really big question. What do you do? But we've talked a little bit about laser optical communications, but saying it is one thing and then doing it is another. Yeah, well the keyword there is optical. And so what I do is I build optical instruments for telescopes like this one here and a lot bigger. And optical physics is sort of my background. What that means is you play with light and how it moves through materials, how it interacts with materials, and what you can do with it. So in this context, that's how you can move data from one point to another using lasers, doing it over, you know, from satellites to ground, doing it between points on the ground. A lot of different scenarios. You can think the classical one as fiber optics as fiber optics cover the earth. And lasers are used to transmit data everywhere all the time, but you can't plug a fiber into every location on earth. So sometimes you need to go through space. So I do like that analogy of fiber optic cables because I think people just think there's these cables and I could hook up a computer and wanted another and all of a sudden I have Netflix, right? It's a little bit more nuance than that. And now when we start talking about with space transmission, the telescope, which is, so this is going to be one of the test telescopes for the first station that you're building here, right? Basically, yeah. And so this is what? .7 meters. And as we talked about before, that's the width of the mirror. Now what normally would this allow you to see or communicate with in terms of distance? Yeah, okay. So we can get to the moon with a data rate of 80 to 100 megabits. So a really, really good internet connection at home. We can get to the moon with this size telescope. We can do a lot faster than that to closer orbits, to synchronous or low earth orbits. So I mean, 80 to 100 megabits to the moon with this is, it's faster than what I get as I said, plugging in at home. So how does this work? Is the telescope now acting kind of like what the fiber optic cable is doing? Is this the medium that's transmitting through or how does it actually kind of work at detail? So the telescope itself acts more like the laser where the larger the telescope is equivalent to a higher laser power, which means it can be transmitted further. The medium itself is free space. So it's the area between you and the receiver or if you're the receiver the other way around. And so the bigger the telescope, obviously, the bigger the laser and therefore than the more data you can transfer. So at a, you know, 80 to 100 megabits per second to the moon, is this kind of what the requirements are needed for the Artemis mission as we talked about before? Yeah, that's right. That's about it. So that's what NASA are aiming for to do a demonstration of that order. They did a demonstration almost 10 years ago, 622 megabits to the moon. But that was a slightly different setup and very specialized equipment. This one's a little bit more generic and a bit easier to achieve. To go beyond the moon, you can increase the diameter. So if you're talking about, say, a four meter diameter like the AAT at Sighting Spring, you'll get out to around Mars, maybe a little bit beyond and there you're around the 10s of kilobyte level. So not super fast, but still a really big achievement for what you can do with lasers and compared radio dishes where to do the same thing, you need a 70 meter dish. Yeah, I mean, that's, and I think that's kind of the remarkable thing as we visited to the bill of a four. You know, they were using the 70 meter dish to talk to Voyager and it was in the kilobyte per second. It was bits per second. And so four meters, and he said, I mean, these are telescopes that we have on Earth that are, we know how to build and at this point are relatively, I won't say cheap, but, you know, we're not talking about billions of dollars like the biggest ones. We're talking about lot less and at that rate, there is actually a decent dramatic improvement on the data that we're already getting to Mars. And I guess this is all to support an area in a world where we have lots of data transmissions not just a few science missions, right? Absolutely. So the amount of data that we generate in space today is growing. It's immense. You can talk about science missions. You can, like, things like the James Webb Space Telescope. They're going to have a huge amount of information that they need to transmit down. And they're actually limited in what they can transmit. If you talk about satellites that do Earth observations, so they could be monitoring sea level rises, they could be monitoring ice flows, atmospheric CO2 emissions. Those have so much more data than they can actually get down with radio frequency. They are extremely limited in what they can do. And so it's view that now laser optical communications is the solution or at least eating the solution to this? Absolutely. It's definitely the next generation of what you can achieve for the amount of data that you can move. Great. So, Francis, if we're in this new data-rich world of space and radio waves are becoming limited in just how big it is and how many we can do, and laser optical communications can solve some of the data problems, how do we go about setting up a network of these things? Yeah. So, the problem to date has kind of been chicken egg. Do you have things in space for your ground stations to talk to? And do you have ground stations for your things in space to talk to? And so what we're doing is building, you know, the first of all, will be several ground stations across Australia and New Zealand in a network capacity here at Mount Stromblo. And to support multiple satellites in space, you really do need a network. Obviously, it's a reasonably clear day today, but hasn't been so clear this year. And so cloud is a really important factor. Once you have multiple ground stations, you can start to be beyond the scale of the weather systems. And that allows you to always have connectivity when you need it. And when you have more and more satellites in space, obviously each telescope can only talk to one satellite. So more ground stations will give you broader access to a whole range of satellites in space. And you can also target different applications. So if you're talking about deep space beyond Mars, you might have one mission that does that for a couple of days a month. You might have this one talking to the moon every couple of days. And then other smaller telescopes talking to satellites, you know, every few hours. So yeah, so I guess this is one of the interesting things we're exploring about tidbit billi is, you know, they say, hey, you know, radio is during the day and radio astronomers aren't real astronomers because they can be during the daytime. That's a joke, but not really. So the solution here is to get around some of those weather and daytime problems is just building multiple of them, right? Yeah, absolutely. So I mean, clouds only exist over a few hundred kilometers. So once you have one in the ACT, if you put one in Western Australia or the Northern Territory, you're really mitigating that problem by having those multiple ground stations. If you choose your science carefully, you can get, you know, more than 99% availability due to weather with about five ground stations across Australia and New Zealand. So there's you're looking at five in Australia, and I assume that's from the west coast of Australia to New Zealand. And do you have any coverage latitude-wise as well? Is there any advantage going north or south? Yeah, so not at the moment, but it depends on where the satellites are. So satellites which are orbiting between the poles, it really doesn't matter what your latitude is, whereas satellites which have an equatorial orbit, they go sort of around the Earth. Those ones you have to be within range of the latitude to access those. But the population sort of split 50-50 between the two, so no matter where you put your telescope, you're going to get a lot of coverage.