The Supermassive Podcast - Into the Space Debris Swamp

Episode Date: April 30, 2026

Izzie & Dr Becky think that space needs a spring clean, so this episode is all about space debris. What is it? How big of a problem is it? And what is being done to remove it? With thanks to PhD student Megan Perks from the University of Southampton, who studies how safe all these new satellite constellations are, and photographer Max Alexander, who has created an exhibition all about space debris. It’s called Our Fragile Space and it’s on for free outside of the Royal Astronomical Society until 10th May 2026. Join The Supermassive Club for ad-free listening, forum access, and extra content from the team. And email your questions to [e-mail] or follow us on Instagram, @SupermassivePod.The Supermassive Podcast is a Boffin Media production. The producers are Izzie Clarke and Richard Hollingham. Hosted on Acast. See acast.com/privacy for more information.

But it is the smaller pieces that we tend to worry about when it comes to space chunk. Well, we've been talking here, there's been several collision avoidance manoeuvres. There's one every two minutes currently. All of this shows, though, is that it's not coming down. It's going up and it's staying up. Hello, welcome to the Supermassive podcast from the Royal Astronomical Society. With me, science journalist Izzy Clark and astrophysicist Dr. Becky Smethurst. We think space needs a little bit of a spring clean.

So this episode will be chatting about space. debris. What is it? How big of a problem is it? And what is being done to remove it? Yeah, so we'll be hearing from Megan Perks from the University of Southampton, who studies how safe all these new satellite constellations are and photographer Max Alexander, who's created an exhibition about space debris. It's called Our Fragile Space and it's on for free outside of the Royal Astronomical Society until the 10th of May, 2026, for anyone that listens to our back catalogue, that's this year. But don't worry, if you you can't make it because Max gave me a tool, which you'll hear later in the show. And it features Deputy Director of the Royal Astronomical Society, Dr Robert Massey.

So, Robert, let's dive in. What actually classifies as space debris? Yeah, thanks for that plug. It's not my greatest hit there, I think. I have a great photo. You said that at the time. It's a great photo. Let the listeners judge here.

Anyway, it's space debris, yes. space debris. So this is distinct from natural dustal rocks, the stuff that comes in, so meteorites, you know, comet debris, etc., etc. What we're talking about is the artificial material left in space by human beings. So that includes it's not an exhaustive, but it's rocket

bodies, defunct satellites. And technically I was thinking about this, I guess those dead space probes that are leaving the solar system are not really going to do much harm. You know, Vojian isn't going to encounter anything for rather a long time. Globes. What did you want to do? Don't say that, Robert.

No, not yet. No, no, no. No, no, that's true. That's true. I'm sorry. Cover your ears, Voyager, please. You know, gloves, tools, flex of paint and that sort of stuff. And basically my thought of it is it's like fly tipping and littering in space.

We should stop it. You know, it's ridiculous. And there's so much of it. There's billions and billions of pieces. Most of them are too small to track, which is a huge problem. So we should definitely worry about it. And the debris comes from when we launch things into space, when satellites break down and they're defunct. When astronauts drop things, you know, we're all human.

So occasionally it's going to have. happen. When satellites collide, which has happened quite dramatically once, and in the worst case, when some countries decide to do anti-satellite weapons test, you're not allowed to do it to other peoples, but you can do it to your own. So the US, China, India, Russia have all done this in the last 20 years. And of course, you fire a missile at a satellite and it showers. It creates a huge shower of additional debris. So that's a big problem. Okay. So that's an introduction to space debris, but just how big of a problem is it? Here's Megan Perks from the University of Southampton with the details. If we're looking at Earth orbits, we have about three major regions, which are

known as Leo, Neo, and Geo, where Leo stands for low Earth orbit, and it's the region that's queasers to Earth, so it's between about 200 kilometres up to about 2,000 kilometres above the Earth's surface. And we have Geo, which refers to geostationary orbit. It's a thin altitude band just over about, I think it's 35,000 kilometres. And then we have Mio, which is the middle region in between the two. So we have debris populations that span across all three of them. But if you're interested in absolute numbers, looking at the European Space Agency's current estimates, there's probably about 50,000 debris objects that are larger than 10

centimetres in length. And then we have about 1 million objects that are larger than 1 centimetre. and then if we go smaller again based on statistical models, there's an estimated 140 million debris objects that are between the range of one millimeter to one centimetre in size. So there's a lot of stuff up there, Izzy. Oh my gosh, that is a lot of space junk, okay. And so of those different regions, you know,

we've got low Earth orbit, near Earth orbit, geostationary, which one is kind of the most populated are they all quite messy which one's the worst like where do we see it as a big problem sure so if we're looking at it from a problem perspective we tend to focus a lot on low earth orbit at the moment because that's where we're going to see a lot of increase in the number of satellites and things in the coming years all of the new proposed mega constellations or large satellite constellations are based in low earth orbit so

when we're talking about debris, that's often where people tend to focus, but there's certainly debris in the geostationary environment as well. But I mainly focus on the Leo region of space, and it's quite interesting because in these low Earth orbit regions, we have to deal with atmospheric drag. So altitude plays a really important role when it comes to what the debris population looks like at different altitudes. So at lower altitudes, the atmospheric drag,

experienced by the objects is higher because the atmospheric density is higher. So we have this setup where not all of the debris that's generated necessarily stays in the environment. It gets naturally removed and burnt up in the atmosphere over time. And as a result, some people refer to these orbits as like self-cleaning orbits. Yeah. But that certainly doesn't mean that there isn't any debris there. Yeah.

And the collision risk is still can't be ignored. and there's still definitely debris there. Yeah, it's fascinating. It's quite sad. It's quite confusing because if we think about the first satellite that went into orbit, that was Sputnik in 1957. And then we've just seen this problem grow and grow and grow. So can you kind of contextualize how much of a growing issue this is?

And where have we seen that really start to accelerate? Sure, yeah. So, I mean, unfortunately growing is indeed the way. word for it, Izzy. As you rightly say, Sputnik was the first spacecraft, but actually the first piece of debris was probably the Vanguard One satellite, which was sent up in response in 1958. So even though Sputnik was first, both it and its launch vehicle re-entered in the atmosphere a few months later, whereas Vanguard One is still up there today. The populations have only really continue to grow since, and that's entirely reflective of our increased use of the space

environment. I checked the numbers this morning. It's about 15,000 active satellites in orbit, with the majority of those having been launched since 2020. Wow. More than 10,000 of those belonging to one company, by the way. But we're seeing this really rapid growth in the number of satellites in a very short amount of time. For context, because I always find this a bit crazy, just before 2020, they were just under about 3,000 satellites in orbit. So we really seen a really rapid increase in the number of satellites in a really short amount of time. Sorry. Did you just say it's gone from 3,000 to 15,000 in about six years? Yeah, yeah, exactly. Yeah, then it's reflective of how our launch capabilities have changed.

And, you know, it's really quite substantial increase. Yeah. And it's clear like we need to get a hold of this, but why is that? Can you just talk us through what is the damage that space debris can cause and like, you know, why is it that we're talking about this today because we need to be? The damage that space debris can do really varies with the size largely of the debris object. We tend to categorise the different debris populations in different sizes, like I gave examples at the start. The really small pieces of debris, so less than about one centimetre in size, they might damage your spacecraft. So if you've got solar panels, you can create impact craters. I think there's a lovely image from the Hubble solar panels where you can see these impact craters on the solar

panels. You know, there's probably a very small piece of debris that caused that. But it does cause damage. And as soon as you get above one centimeter, you start to talk about, well, you might be looking at a catastrophic collision, which essentially means that the spacecraft might lose its capability to operate or, you know, fragment into smaller pieces. So we're more worried about collisions with larger objects, unsupprisingly, because they cause more damage and release more debris. But the consequence of that collision largely depends on where in orbit that happens. So how that risk translates to other objects in orbits around it and below. If the collision happens in really populated orbits and you see the debris from it,

you know, spread out into areas where other satellites exist or either at the same altitudes or below, then you can begin to have more of a problem. And if we talk about how we try to wind down satellites in space, what is the current process? Sure. So dealing with your spacecraft at the end of its mission is really important. It's an essential part of various international bodies debris mitigation guidelines where, you know, satellite operators are really encouraged to include a disposal plan. But how operators choose to do that varies slightly depending on the orbital region that the mission is located in. So no matter what, the advice is to passivate your spacecraft, which means to reduce the risk that the satellite will explode by ejecting unused fuel or some other things, so that it's not

going to explode unexpectedly. The techniques are different depending on if you're in geostationary orbit versus lowest orbit. So if you're in geo, it's like a fixed distance above the geostationary operational altitude where these satellites that are moved out of the way at the end of their life. So they're just shifted kind of away, drift off, like, you know, slightly above. Just like a graveyard in space. Wow. Gosh, of course. Okay. Yeah. And it's like moving your car off the motorway onto the grassy verge over the heart shoulder. Yeah, it's still there. But the collision risk to the remaining traffic is massively reduced.

All of this shows, though, is that it's not coming down, though. It's going up and it's staying up. So that's the example for Geostation. Yeah. But in Leo, it's a bit. different because it's much closer to the Earth, you know, so it's far more feasible for us to de-orbit these satellites and burn them up in the atmosphere. The spacecraft must re-enter the atmosphere within either five or 25 years after the mission has ended. So, I mean, again, if we're talking about the motorway analogy, I always like to think of it as like, you know, those massive colossal mega-highways that exist in the world? You've got like 10 or 15 lanes that are stretching across them. You can imagine that you're like driving.

in the fast lane and you've got to take the upcoming exit. But in order to get off, you've got to traverse all of those other, you know, nine, ten lanes worth of high-speed traffic in order to get off that slip road. So it's quite a feat. But the closer you are to that slip road exit, rather the lower in altitude you are, the easier it is for you to de-orbit at the end of your mission lifetime. And so why is it that we can't just burn up all our satellites on re-entry, you know, they're done, they're not serving a purpose anymore?

why can't we just de-orbit all of them? Sure. Well, some of them are derelict. They don't have any propulsive capabilities, so then they're just going to stay there, you know, sometimes indefinitely. You're talking about above a thousand kilometers or so with thousands of years before they would come out themselves.

It's curious because I always think the idea of spacecraft completely burning up in the atmosphere. As a sustainability strategy sounds a little strange, it's a far better option than abandoning them. That being said, there are growing concerns about what this impact might have on the Earth's atmosphere. So aluminium and various alloys are commonly used materials in satellite construction. And there are some recent papers that have raised some concerns about aluminium oxide gets produced during ablation.

Ablation is just a fancy word for burning up in the atmosphere. But particularly the impact that can have on the ozone layer. And they say that we might not see the impacts of that 30 years in the future. But this topic is the inspiration of this really cool satellite. It's known as Lingosat, which is a satellite that's made almost entirely out of wood. I think it's Kyoto University, actually, and it was launched in 2024. I believe that it didn't even use any screws or bolts. I think it was just put together using traditional Japanese methods with a few electronics inside,

which is super cool. But yeah, just to see what else can we make these satellites out of that might be a little kinder to our atmosphere? That is fascinating. So on that theme, and I think it's... the question that everyone wants to know when we said we were going to be doing an episode on this topic and we asked for questions, so many people sent in, what can we do? Is there a way for us to clean up the debris in space? You know, how can that be done safely and how are people researching now? What are the solutions, Megan? Sure. Yeah, I mean, at this very moment in time, there are

certainly technologies that are under development to remove debris. Like I said before, some of them decay naturally, so they don't need removal, but those are a bit higher up or they're really heavy that they're going to need active debris removal. There's companies like Astroscale or Issa's clear space mission. Some of them range from like a giant grabby claw that's attached to a spacecraft with the idea that it would rendezvous with a debris object, grab it with a giant claw and drag it down into lower orbit so that it can decay and burn. But the thing that I always find really fascinating with that technique is that a lot of People forget that these debris objects are not stable.

So they're often tumbling and they're rotating as they're moving around their orbit. So if you want to send a mission up there to grab it, not only do you have to get really close to that debris object without colliding. It's no easy feat, but that you would then have to do a propulsive burns in order to put your spacecraft in a rotation around the object, so that it's essentially in sync with each other, before you could even think about reaching out and grabbing it. All of this while it's hurtling around the Earth at many kilometers,

per second. I don't know about you, but I get a bit dizzy just thinking about that. But there are other options that are being explored. One of them includes possibly firing a laser beam from the ground, essentially in the opposite direction to the debris object's direction of motion, with the idea that you could use the laser to slow it down so that it reduces an altitude and can reenter naturally. That one comes with a few, I'll use the word, challenges. But we also have things like drag sails. So these are fold-out sails that can be either already attached to the spacecraft before it's launched, thus increasing the force that it experiences from atmospheric drag that will hopefully pull it down and have it re-enter and burn up in the atmosphere. So there's lots

of weird and wonderful ideas. None of them are actually been proven yet if we have these really huge numbers of large constellations satellites. You know, you can buy the biggest mop in the world, but it's still no match for Niagara Falls. Thank you to Megan Perks. So Becky, can you clear something up for us? Pun intended, absolutely. So there is this assumption that space debris is like this sea of junk that's really close together and we kind of have to duck and dive to avoid it.

That's not quite the case though, is it? No, I mean, just because space is really big. I was trying to think of a good analogy for this. Like if you think about how many planes you see on flight radar at one time. Okay. Yeah. And they're always concentrated around big airports. And then obviously they spread out, say, across the Atlantic and things like that.

And then if you think about when you're on a plane, if you look out of a window, how many planes do you see? Right. I mean, sometimes, like I've got a few planes. Like occasionally I might see a plane out of the window. Again, if I'm close to an airport. But otherwise, you're not, you don't tend to see planes out of your window, right? So despite the fact that air space is very dense with planes, when you're actually up in the air, you're not like swimming through a seat of planes, right? And if there are any collisions between planes, the majority of them are on the ground, like actually at airports, right, and not in the sky.

So I think it's a similar thing with space junk. There's just lots of places it can go once it's up there. You know, you don't you no longer have two dimensions because you're on the ground. You have three because you have altitude as well. So what we do is we do track the big stuff so that it isn't an issue. for say like, you know, the Artemis mission, for example, that recently launched and looped around the moon, Artemis 2, right? They did hold that launch for about 10 minutes because they were like,

hang on a minute. There is some, so a big piece of operating space tech that currently we have to wait to go past. It wasn't necessarily space junk, but they knew that that was going to be there, so they held the mission for 10 minutes, just to be on the safe side, right? But it's not like it's sort of once it's up there, it's having to constantly maneuver Star Wars Kessel Run style around a load of space junk, right? but it is the smaller pieces that we tend to worry about when it comes to space junk

that can go on track and can be a bit of a danger. Yeah, and uncontrollable, I suppose. Yes, yes. And so have there been any near misses? I'm thinking like with the International Space Station or like any other missions? Yeah, the International Space Station, the ISS, that's been hit before by Space Junk. So that's actually left like tiny little holes in like the Canada arm, which is one of the experiments on board and stuff outside the ISS.

Back in November 24, the ISS also had to perform, and I love what they call these, a predetermined debris avoidance maneuver, a P-dam, just to get away from debris from an old satellite that broke up back in 2015. Again, NASA was tracking. We actually have had a satellite collision before, as Robert mentioned before. So the most famous one was back in February 2009, so it was two communication satellites. It's one active American communication satellite and one old Russian military satellite

that accidentally collided at a speed of 26,000 miles an hour. Yeah, at about an altitude of about 490 miles. Yeah. And it's a really, really big deal when this happens because a collision like that, you know, sort of completely explodes both satellites, for one of a better word, and you end up with a lot of shrapnel. And so then you have this essentially like a cascade

of a lot of smaller debris that's all moving at high speed, which ends up essentially acting like lots of tiny bullets that we can't track. And that's something that's hit the ISS before that leaves holes in things like shields and solar arrays, things like that. And so the big danger is something called Kessler syndrome, where that tiny junk then hits into other satellites, destroying those, creating another cascade of tiny junk and so on and so on. You've got like a chain reaction, just a cascade of ever worsening space junk problem over time. So right now there's thought to be around about 130 million pieces of space junk orbiting Earth, but not all of those are tracked. And then I guess it's just that domino effect, isn't it? Like one goes and then you can see how that just ripples through all of that.

Yeah. So it's a big deal and it's why a lot of people are trying to solve this. Personally speaking, I love it when science and arts just come together and, it's even better when it's trying to raise awareness of a problem like space debris. So this is the topic of a photography exhibition by international photographer Max Alexander. And as I mentioned at the start, it's on until the 10th of May, 2026, outside of the Royal Astronomical Society. So here's what happened when I met Max for a whistle-stop tour of his latest work. I am standing in my favourite courtyard in London outside the Royal Astronomical Society. and it's obviously always gorgeous, but today it's even better because there is an exhibition here by Max Alexander,

and he's joining me now. Hi Max, how are you? Hello, great to see, Izzy. This is amazing. Can you tell us about this exhibition, our fragile space? Absolutely. Well, our fragile space is a photography exhibition. It's about three things. It's about all the economic, scientific and societal benefits we get from space. It's about the growing problem of congestion of satellites and space stabbary in space. including the impact on astronomy, and what are we doing about the problem,

so-called space sustainability and regulation and policy? So let's look at the first chapter of it, if we say, so the benefits of the space industry and the space economy. Can you talk me through some of your favourite images from this chapter? What are we looking at? Absolutely. Well, the first photograph was taken in Chile at the European Southern Observatory of a Spanish astronomer.

I took her out from her control room when she was operating the telescopes, the very large telescope, and put her out beside the Milky Way. And my background's really in astronomy. So the loss of the night sky is important to me and what we're doing in space. So that's a really important key photograph for me. And just to describe that we have, Amelia, sat in a chair, kind of lit in the foreground and behind her there's this amazing milky way as the backdrop,

like the lighting of it. I'm just like, how have you got the light on her face and it still captured the darkness of the night sky? It was actually three of us taking this photograph. So I've got a flash off camera. So if you get all techy here, so it's a 20-second explosion. to see the lights of the Milky Way and the stars and the dust lanes. And then we've got her lit by flash and somebody's walking around with a torch as well to light the foreground. So three people to make one picture.

It's absolutely beautiful. Thank you very much. So shall I talk about some of the other pictures here? Yeah, let's go for it. Okay, so I've got a photograph here from UMMetSat. So they provide the satellites and the data for weather forecasting. But this is a key thing. You know, if we can't use the mid-Earth orbit is where most of these satellites are for where weather forecasting. So if those orbits are lost in the future, then you won't be able to provide

weather forecasting. So they're one of the project sponsors and they're concerned about that environment. If it gets too crowded and busy up there, it could impact on their weather forecasting. If we move over onto the other chapter, it's like it's the cost of this, right? So what is that balance? We were walking around the exhibition earlier and trying to put the world to right, I think, but you gave a really good analogy of the kind of state that the Earth is in at the moment. Yeah, this chapter is called The Cost of Living. I'm going to use a long word here. It's about anthropogenic change.

So how we're really polluting on the land in the ocean with plastic in particular, which is an interesting metaphor for space debris, carbon in the atmosphere. I fly a lot for my projects, we're all to blame as a species. And now this fourth domain of space. and it's really, in low Earth orbit, it's really just 400 kilometers up in that kind of regime, 400 to 1,000, something like that. And it's really become part of this environment by virtue of putting material up there. So that's to put it in that context.

We don't want to ruin that environment like we have on many of these other domains. And it's hard, though, because how do you capture that? Because this is the thing with Space Debris, right? Like, we talk about it a lot, we're all concerned about it, but we can't see it. So how do you translate that to images to make people who come to this exhibition care and pay attention to that? Yeah, there's several ways to do it.

I mean, the use of space is for us down here on Earth. You can do satellite trails, so I do long exposures where I've got a camera where I rotate with the Earth's rotation and do one-minute exposures and stitch all those together so we can see those satellite trails. I've photographed examples of space debris. I've got privileged access because I work in the space industry,

space agencies commercially as well. So every time I go to, we've been to a clean room over a period of a year or so, every time I went to a commercial company to a museum, I asked if I could photograph examples of what's in space, and then we created a montage. So the idea is really to make the invisible visible and use art to communicate what's going on in space. What have been some of the hardest images

as part of this exhibition that you've created? Well, I would say the Pentraeifan picture with the satellite trails. So I had this sort of this prehistoric stone age experience. So this is Pentre Efan. It's a burial chamber. It's got a 16-ton capstone's been sitting on those three points for 5,000 years. It's just four miles from the Priscilla Hills where the stones from Stonehenge come from, and it predates that.

And then we have Starlink and the International Space Station, and all these satellites and rocket bodies coming over during that time. So it was a really powerful experience to bring those two worlds together. Well, that was three years ago. guy's got busier. In many ways, it's sobering as well. Yeah, because we have this monument, but then in the night sky, it's just covered with lines of different brightnesses. I mean, it's almost like a grid. There are so many of them, and that's just two and a half hours. It is, and it's got busier, and there are about 15,000 satellites in space now. There are

licenses around the world for more than a million. That won't happen, but if we go up in order of magnitude to 100,000 with the state of play, there's, well, we've been talking about. We've been talking here, there's been several collision avoidance maneuvers. There's one every two minutes currently. So if you go to 100,000, we're getting into seconds. So again, is that sustainable? So those questions need to be asked. And to me,

sadly, it feels like the sky's being scratched. And you've travelled the world with this. You've got so many voices involved. One thing that really stands out for me in this exhibition as well is the section on our shared sky that you've worked with indigenous communities to translate

their relationship with the night sky, well because that is so important historically. So what was that like working with those communities and I'm featuring that in your art? It was amazing, it was a unique experience. I worked with about six different communities around the world. So they've used the night sky for thousands of years. I mean, I'll give you one example,

a square kilometre Array Observatory in South Africa and Australia. So they're partnering up with Wadria, Aborigines in Australia and the San people in South Africa and other communities. So a lot of indigenous knowledge of the night sky has been lost. So they're actually helping to redevelop that to reawaken it. And I think this is a renaissance in those countries. They've learnt their lessons from other observatories around the world where they haven't really paid attention to that, and actually they're making a real feature. But that ties in with all our love of the night sky,

both Western and Indigenous. And those things are really coming together by the work of places like the Square Kilometer Array. Yeah, and it's really important to have that involved. So I know it's a whistle-stop tour, but if we look at this chapter here, that's what we leave behind. I mean, there's this amazing photo of Tim Peake. Tell us what's this section about and how did it all come together? Yeah, well, I've got to know Tim quite well. I photographed him while he was training before he went to space, went to Star City before launch. So he was very interested in my cameras because it's the same cameras on the International Space Station. So I gave him a bit of informal training before he went. But he did put me on his email list and

I trained him for his photography when he was in space. It was very cool to get an email from space on your phone. It felt like showing the next person in the street. So it was a unique experience in a photographer's life to do that. It was amazing. So he famously took this photograph here of the Coppola window and the International Space Station so it's a crack in the glass.

They'd have to do a chemical analysis, but it may have been caused by something like a fleck of paint. If it had been a bolt, that would have been a very bad day for the International Space Station. Sorry, I need to respond to that because if that's from a fleck of paint, the image of it is, like, you've got this black square and it just looks

like someone's thrown a rock or something at your windscreen. It's that sort of effect. So that would have been very small and it shows just the risk that we're at here, right? And especially astronauts. I think the key thing is, you know, probably we've got a very informed audience here we know about velocities in space. But this debris is travelling 17,500 miles an hour. You've got the approach velocity for the other object. So these are tremendous velocities 10 times faster than a bullet out of a gun. So a flack of paint can be a a bad day for your satellite. Certainly a bolt can be very destructive

for that. This whole exhibition does end on a note of hope, right? There are people working out here to find solutions to work out what we do about space debris. So who have you worked with on this last section and what do you think the solutions are?

I've liked to think we're in an optimistic note. I think really what's coming out of this is an opportunity, an economic opportunity. So the first adopt of these new so-called space sustainability practices will gain commercial advantage from that. So that's important to say.

Part of that is the observance, at least, of astronomy and how that impacts on them. So here we've got examples of de-orbiting satellites. We've got three different engineers here working on bringing satellites down with a drag sail with a magnet and robotic capture of satellites and rocket bodies. Thank you for showing me around. It's been absolutely beautiful.

And a lot of food for thought, I think, as well. So what's next? Are there any other projects on the horizon? Well, I'm working my way through three projects from Space Situation Awareness, SSA. So this is my space debris project. I've done one on space weather, which was also opened at the Lloyd's Building here in London. And my third opus will be on asteroids. So I've had an asteroid named after me for this work here. I think that's the biggest flex possible. That's amazing.

Just wanted to drop that in there, just to work that in, this 12-kilometer wide asteroid. And so my next project will be on planetary defence and asteroids. So I would like to save the world. That's my next project. Yeah, I mean, that's no small task. So good love with that. Thank you. Thank you to Max Alexander.

And Robert, the Royal Astronomical Society have been a big supporter of this exhibition too. So how are you working with Max and have you seen any impact of this exhibition and on the wider space industry? Yeah. So I have worked with Max on this. from the very start with our fragile space and it's the only exhibition yet has got this photo of me in it, but because of our work of satellite constellations

and light pollution on the ground, you know, Max approached us and we've talked to him over the years about this stuff. And I put an essay in the catalogue too. And he's been photographing astronomers and astronomy for a really long time in the space sector. So we're really pleased to work with him on it.

So this is the first time the exhibition has come to Burlington House, which is the courtyard outside, the Royal Astronomical Society were part of part of Burlington House itself. and we think that many thousands of people are going to see it over the eight weeks that it's on because they're on their way to the Royal Academy to see art exhibitions. And it's nice because it's very public.

So it started life at Lloyd's of London, which is a big insurance breaking house. And essentially, you know, that part of the city you don't get in the building that easily. There's security controls and all the rest of it. What's really great about this one is that you can just walk in and have a look. And then after that, and I give credit to Max for this. I mean, there's lots of people involved with this stuff. The score was quite difficult to point in one person, but I've no doubt has been influential because he is what, I don't know, what the kids, from my perspective, would describe as a visual storyteller, right? So he's creating all these fantastic images and people are seeing it.

And, you know, we saw the creation of something called the Astrakata. I'm going to forgive you if you don't know what that is, but if you do, it's... Is it like the Magna Carta? Is that a pun? Yeah, yeah. So King Charles is very big on this, right? So you've got the Magna Carta from 800 years ago, and then he had the Tama Carter. Terracarta, which was to care for the Earth. And the astrakarta is an initiative of something called the Sustainable Markets Foundation,

which is bringing companies together. And the motto is to care for the infinite wonders of the universe. So we could quite easily get behind that. Now, it was launched, I have to say, to zero publicity. I don't think there was any press coverage of it at all. But, you know, those in the sector know about it, very nice logo and sold. And on the same day, we signed something called the Earth Space Sustainability Initiative, which is doing the same thing, and brings him the wider.

the wider communities of academics and so on as well. And the whole premise is to look after the near space environment. It includes protection of the sky, dark and quiet skies that we've talked about before. But it very much includes reducing space debris, managing that stuff, ensuring that the space environment is kept in good order. And Max has been really involved with that from the start as well. So credit to him for doing all this work. This is the supermassive podcast from the Royal Astronomical Society with me, astrophysicist Dr. Becky Smithhurst and science journalist Izzy Clark. So let's get on to some listener questions.

Becky, Harun Daniel on Instagram asks, how dangerous is space debris for future humans planning to live in space and on the moon? Well, in terms of humans living in space is one of the biggest issues for space stations, right? It's dealing with that constantly worsening situation of that cascade of chain reactions of space junk hitting into other space junk. that tiny sort of bullet of space junk moving at 1,000 miles per hour is a big issue if it hits your space station, yes, but also if it hits your space suit on an EVA, right, a spacewalk, basically. I personally would not like to go out like that. Just saying.

No, thank you. It's not much of an issue for, like, humans thinking about living on the moon in the distant future or the near future of nothing is its way, I guess, at least not currently anyway. So the lunar orbits of the area of space around the moon that satellites in orbit in is fairly free of space junk. We've got a few working satellites with the likes of the lunar reconnaissance orbiter and a few defunct satellites that have been left there. But otherwise, like, in comparison to Earth, there's absolutely nothing. Ideally, though, we'd need to keep it that way. Yeah, you will exactly.

The danger is if, say, NASA or a commercial company or any other space agency want to build a moon base, so actually on the surface of the moon base station, is that, construction from that could create a similar space junk problem around the moon with its own worsening situation due to Kessler syndrome and the cascade of collisions and things like this. You know, if you think about sort of like how would like a lunar space station be constructed, it would probably be mostly constructed like the ISS was on Earth in modules that were then fitted together in space. But that would hopefully minimize space junk. But at the same time, you've still got astronauts having to piece these things together, dropping spanners, that kind of thing. you know, like there's still issues. So perhaps if people think about this carefully, we might be able to avoid the situation

that we've ended up with in Earth. But, I mean, you're not going to need things like weather satellites for the moon and things like this. So there is going to be a lot less things sent into orbit around the moon. Anyway, but the moon is also smaller, so it has less real estate when it comes to orbital space. So there are a lot of things to consider. Yeah, I feel like we've got a really good record

of putting on grab your hands on. You can say, oh, humans were here. Okay, cool. Yeah. And Robert, the purring pulsar wants to know. How can you tell if a shooting star is a meteor or space junk? Yeah, thank you, purring pulsar. And I looked at this and I did have some vague memory of the difference.

And the key distinction is the incoming speed and the pattern in the sky. So meteors and fireballs, so now those natural space debris, tends to come in really quickly. And if you look at the Eta Aquarius meteor shower, which is in May, then they come in at 66 kilometers a second as the typical speed. So really high speed, much faster than so. The astronauts had to launch an Artemis to get to the moon. But space debris from Earth orbit tends to go in about between 7 and 15 kilometers a second. So it's noticeably slower as it burns up. You know, you still think that's blazingly fast.

But of course, it's really quite high up as you're watching it. So even at that speed, it can take a while to cross the sky. it can be even minutes. It moves more horizontally as well because this meteor showers, you know, very often stuff is coming in directly. There are Earth grazers, which are an exception. But the majority of it is coming straight at you,

whereas with something like space debris from Earth orbit, it's coming at a shallow angle. It takes longer to come in. And it can be bright. It can break into pieces. You know, if I're very unlucky, some of that hits the ground. And you can see this pattern of debris. And I was thinking about this.

I thought, when I was about 13, I remember seeing in my back garden, something which looked like, a weird meteor, you know, like something breaking up. Now, this was, I kept, well, I was in 1988, something like that, but the 1983 or so. But thinking about the pattern of it now, I'm thinking, did I see reentering space to Brise? I've now sent myself the homework of trying to find out if there was a big satellite reentering

in 1983. I've got absolutely no idea. But, you know. Please report that. Exactly. We want to know. Somebody on the podcast who's listening as any way of finding records of this would be really interesting or gets to me because it was just, it was visible over the southern

the UK. And it was like, oh, that was very dramatic. So now I think, yeah, that might have been space debris. Oh, wow. And Becky Loder, who is a long-time listener, asks, is there a risk that any of us here on Earth can be hit by a piece of debris that fell from orbit? Unfortunately, Loder, yes. It's not a high risk, but it's not zero either.

So some listeners might remember when Skylab was deorbited back in 1979. It fell to Earth with a load of debris that landed. over Australia. Or we also had the recent re-entry of the Chinese Long March 5B rocket over Malaysia a few years back as well. Thankfully, in both of those scenarios, no one was hit by anything, but large, large chunks fell to earth. You know, you have to remember, like, a lot of this material does burn up in the atmosphere because it gets so hot, but the things that are going to survive that are the big chunks of metal, which obviously can cause a lot of damage when they land back on Earth. And as far as we know, there's only one person.

that's ever been recorded to have been hit by space debris. That was a woman called Lottie Williams from Tulsa, Oklahoma, USA. It's always the USA, isn't it? Always. If you are, so what country have we like? The US. But she was struck harmlessly, thankfully, in the shoulder by a piece of space debris in 1997.

She picked it up, she took it inside, she brought it to the authorities. They came and got it the next day. It was about the size of her hand, which I thought was pretty big. I'm like harmlessly in the shoulder. Like, about the size of your hands. Yeah, that she wasn't hurt by that.

Yeah. It was thought to have come from a Delta 2 rocket was what it was thought to have come from. So, yeah, I mean, like I said, chances not zero. Yeah. Still that. And so there are many different estimates on the chance of space debris hitting someone. Most are in the sort of one in 10,000 range. But that's the chance of any single person on earth being hit at any one time, like anywhere in the world.

the chances of like one specific person being hit such as me or you listening right now are more like the order of one in a trillion right manishingly small but not zero exactly and actually when I was walking around the exhibition with Max there are parts of it where he shows who else works in the space sector and there is a photo of the people working at lawyers of London who are like a space insurance group

and he also featured a space lawyer and you're like all of these people that have to think about these things. Yeah. Yeah. I love that idea of like a space actuary. It's like, what are the chances of someone being hit and killed by space debris and a company then having to pay it?

Like that's just crazy that that is now conversations that people are having like in offices around the world. Yeah. Yeah. Yeah. The situation that we have created for ourselves. Yeah. Exactly. Well, on a good note, Robert Astropeep 5 wants to help and they ask,

Are there any citizen science projects to get involved with surrounding space debris? So the answer is yes, sort of, but not like the ones we're used to in things like the zoo universe, which brings together all these citizen science projects where you can look at astronomy data, you know, can do things like find exoplanets, classically identify galaxies, all that sort of stuff. Big up galaxy zoo, that's my project. And I really encourage people to look at that. I can do my PhD thanks to Galaxy doo. There you go.

Becky's PhD was sorted because of that. So there are things. There's something called the CSAT L web resource, which seems to be very, very anarchic. In other words, there's nobody particularly leading it, but people just contribute things. And they're encouraged to report observations. And they sometimes have quite sophisticated equipment. Because I guess if you're looking and tracking pieces of debris, you know, you need, I mean, you can do big satellites with a very goodoculars, right. But if it's very small, you probably need a reasonably sophisticated telescope.

So there are sort of adjacent things. The University of Plymouth has just announced this cosmic dust in the city project, which is more about collecting evidence of natural micrometeorites. I thought I would give it plunge because it's quite fun anyway. It seems to involve putting trays on your reef to collect debris from space, which sounds quite fun. And then there's the sat. And how much bird pooed do you think those trays collect? There will be some.

I think we can assume there's going to be some. What is the ratio of space to create a bird poop on those trays? I'll leave that to the researchers to answer that question. It depends where you live, but I'm sure you're right. And then there's the sat hub section of the I use center of the protection of the dark and quiet sky. And that's what the observers tracking satellites. And some of those might lead to debris. And they've got, you know, pairs of binoculars and a good knowledge of the night sky at the very least.

So they can say where they are in the sky. So you can help with those things. I think we should include the link to them in the show notes and so on. But the, Izzy's nodding nicely at that point. Yes, I'll find them and I'll put them in the show notes. Excellent. Excellent. So I do encourage people to help.

If you've got some equipment and a modicum and knowledge of the sky, is probably going to help. It's not the easiest thing to get into. But it is really valuable. I have to say that, you know, being involved with it from even the dark and quiet sky's perspective, we really, really need the data. It's really helpful if people contribute to this effort. So good shout, Astro Pete. We really appreciate it. Yeah, so nice. And thank you to everyone who sent your questions. Please do keep sending them in. You can email them to podcast at rias.ac. dot UK, find us on Instagram at SupermassivePod. Or if you've joined the Supermassive Club where there is a link also in the show notes,

you can just post on the forum and we'll take a look. So shall we finish with some stargazing, Robert, what shall we be looking out for in May? Yeah, and we're going to divide it into the northern hemisphere first for reasons we'll come to in a minute. So late spring is a really good time to see galaxies still. You know, it's the Milky Way, which we all love, is out of the way. It's around the horizon. So instead of looking into our galaxy, you're looking out of it. So that means you see things that are outside the galaxy, including lots and lots of galaxies.

There's less stars, fewer stars in that direction and less obscuring dust. And there are these things we've talked about, like the Virgo cluster of galaxies. You know, you can get a medium-sized telescope, see loads and loads of galaxies nearby. The Virgo itself is high in the south with the bright star spiker. And if you look higher up, because I was thinking about this about good targets, you can see the whole Eversa Major, the great bear, centered on the plow, which, you know, or the big dipper if you're in the US. It's got galaxies like Messia 81 and 82,

and they look really good, actually. I was like the other night, and I thought, one looks like an edge-on galaxy, one looks like a sort of irregular one. They're not bad, you know, there's one that's kind of spiral shape, almost a spiral shape.

There was always really hard to see the arms, but, you know, they look pretty good. And then there are globular clusters. These are things, again, that you tend to see in that, you know, well, actually all over the sky, but there are some down at ones like Messier 3 in Boatis, and these can have a ten. or hundreds of thousands of stars in them.

And they look round and fuzzy in a pair of binoculars. But if you get a bigger telescope, they really do. They look like they can myriads and myriads of stars, these really beautiful objects. So if you ever get a chance to say a public observing unit somewhere and you look at something like that, it's really incredibly special, rather. And there's also a so-called hidden treasure. There was an astronomer called Stephen James O'Meuro who cataloged these objects people hadn't seen.

And the one he pointed out is that the constellation, Coma Berenesis, which is up above Virgo, Berenys's hair, which is a beautiful name, although it's actually quite modernish, you know, as in only a few hundred years old, it was designated. That's very well known for its galaxies, but it actually is an example of a big open cluster. So you can just look at it, you know, take a actually nothing other than a pair of binoculars is going to help because a telescope will only see a tiny part of it, but you can enjoy the view there. Okay, so that's a lot for the galaxies and stars. What about planet-wise? What can we see? Yeah, so planet-wise, Jupiter, we're getting to a bit of a fallow period.

So Jupiter is sinking down into the sunset. Venus is kind of coming up towards it, getting easier to see. They'll actually get quite close together in June. And so Venus is going further than the sun in the sky. And if you look with the telescope, you'll see it's getting closer to the Earth. It's getting bigger, but the phase is shrinking as well. Sadly, the two comets we plugged last month didn't come to that much. I know.

One of them was destroyed as it went around the sun. So I was watching the Soho images and seeing this thing kind of, in and then, you know, we looked and looked and there was just a little plume of dust coming up. Oh, I was so sad. So that was very sad. So that was that. And the other one, pan stars in the morning sky, wasn't as bright as we were hoping for.

But solar activity is still great. So we had a report of a brighter rural display, even from North Norfolk. So that's still going on. There are still sunspots. There are still displays in northern lights. Not like they were a couple of years ago, but they're still around. And we've also had a message from a new listener, Anneliese in New Zealand. Hi, Alice.

She said she's recently got into space thanks to Project Hail Mary and the Artemis 2 launch. I mean, what a time. And says, is there any chance that she could get a southern hemisphere stargazing check? She's already planning to see the Lyrid meteor shower, but what else is out there? Yeah, so high again, Annalise,

it just makes me think, I want to be in the southern hemisphere, looking at the skies there, because in many ways there's so much better. But, you know, no obvious justification for a media trip but I'd like it. You should totally do a podcast recording in the Southern Heaviscia for anyone to something.

I'm like, oh, we should get them over there. Yeah, exactly. Yes, if anyone would like to host us, thank you, please let me know. Email podcast at raf.orgas.org. Thank you. Frankie L. Camp, if it gets us there. Yeah, anyway, so the Lurids are in April shower. So I hope you had a good view, first of all.

But in May, you've got the Aeto Aquarius Meteor Shows, which is coming up. And that's actually best for observers in southern countries. You might get, say, 30 an hour that you can see between the 5th and the 6th and May. It can say in the north as well, it's just less good. There is a problem which is there's a waning gibbous moon, so that'll wash out. That's a pretty fat-looking moon. It'll wash out a lot of the meteors, but there'll still be some. And if you stand maybe it with behind you, you might see a few.

And you're also lucky enough to be heading into the southern winter, if lucky is the right word. But you get the darkest nights, and you get the view of the heart of the Milky Way, Sagittarius and Scorpius, really is very much. spectacular and even now you can see Virgo high up in the north, Galaxy is well placed for the south as well as the north. And higher up is Rigil Kentoris, Alpha Centauri, so that you're closer start to the sun or one of the closest starts of the sun. Crux, the southern cross is high up there as well.

And the southern Milky Way is already looking pretty good. And I'd look out for things like the jewel box cluster, which is a beautiful, colorful open cluster. You know, it's great with a pair of binoculars. But pick those binoculars up, look at the Milky Way because Scorpius and Sagittarius will soon be there and they'll be almost overhead in the southern hemisphere and that is a really special sight

so we're not at all jealous of your spectacularly beautiful skies. Yeah, I've seen Sagittarius low down before but never overhead like that because I've just never been in like the Southern Hemisphere winter because I'm always like, well, it's nice in the Northern Hemisphere, I'm going to stay. Yeah, yeah. Need to go.

Yes. Yes. And if anyone is listening in the Southern Hemisphere and gets a photo of any of that, then do send it our way. But I think that's it for today. We'll have our usual Q&A in a few weeks' time and then we'll be back with another main episode after that.

Contact us if you try some astronomy at home. It's at Supermassive pod on Instagram or you can email your questions to podcast at rAS.ac.ac.org And we'll try and cover them in a future episode. But until next time, everybody, happy stargazing.