Lucy in the Sky
with Debris

Speakers
Alice Gorman (AG), Isabella Ong (IO), Seet Yun Teng (YT)

YT

Your book, Dr Space Junk Vs The Universe: Archaeology and the Future, is a point of inspiration for us. We think a lot about how we can bridge the gap of visibility of the space debris issue that has to do with distance and scale. In your book, you compare the weight of space junk in orbital space to that of elephants in order to bring it back into view and comprehension. What are your thoughts on the perceived separation of outer space and Earth, and how do you think we can start to bridge this gap of visibility?

AG

This is a question I've been thinking about lately. If you get down to space junk of smaller scale—the tiny particles which are floating around alongside naturally-occurring interplanetary dust—you have a continuum of matter from Earth to outer space. We often think of the atmosphere as this thing that just stops, but in fact it keeps going, although at a very, very low density. The atmosphere actually extends beyond the Moon, so we don't have a sharp dividing line between Earth and space. In your project, it’s a nice twist that you’re overlaying space junk on old celestial maps. “Natural” stuff is often separated from “manufactured” stuff, whereas they’re actually all around there together. So I think in terms of visualisation, there's not a lot that shows both of these things together. You've got visualisations from NASA and ESA with little dots of light; and you've also got other images which show you a cloud of junk, as though someone's taken the garbage can out, with bits of machinery and metal and stuff that are all similar in size. And there's not a lot in-between, is there?

I think people do tend to think of space as very separate. Interestingly, Australia is one of the few nations that actually have a legally-defined boundary between Earth and space, at 100 kilometres. Because it's so difficult to define that boundary, few places do it; but in Australian legislation, it's 100 kilometres – sort of the notional Kármán Line. So, yes, I think it's a really interesting question, because a lot of the time, when people hear the term “space junk”, they don't have any visuals. If they do think about what junk means, it’s perhaps that idea of the stuff that's put in the rubbish bin, or scientific, not-to-scale representations. There are, perhaps, pictures of individual satellites or spacecraft, but they're outside of their context and you don't see them as part of the broader environment. So yes, I think that's a really curly problem.

IO

Yes, I think that's exactly what we're trying to tackle in our project. This idea of a material imagination of what space junk or space debris is and looks like. As such, as part of our research, we're trying to collect material evidence of space junk. There isn’t much – the most provocative image that we have is of the SpaceX debris that fell in New South Wales last year, with their charred textures and iridescent metal due to the heat and pressure during reentry. Recently in Western Australia, they fished out a capsule from the ocean which belonged to the Indian Space Research Organisation. Another example of material evidence that we're really taken by is an image of a panel from the Hubble Telescope that has been impacted by both natural and artificial debris over 15 years. People often think of space as empty, and space junk as objects merely floating in space; but in fact these things are moving at multiple times the speed of a bullet, and it's a very violent environment. So what we've been trying to do is to collect all the  material evidence of this environment. But as you said, there isn’t much and we usually don’t see the objects in context of their orbits.

AG

In Sydney, HEO is one of the first few companies who are using onboard cameras on spacecraft to image other spacecraft. It’s not on that kind of resolution like the Hubble panel where you can see the impacts of individual debris. But the thing that's different about it is that these images are spacecraft-to-spacecraft, and so you do see things in their context. They do this in order to perform a condition assessment – how it’s looking after it’s been in space for a duration. This is relatively new – they've been doing it for a few years, but they've just developed this new software to get more detail out of the images. I like this idea because I'm sure a lot of people have never  seen pictures like that, and certainly have never  seen them all in one place. It makes the case that this damage is being done, and it makes it more real. Because the other thing that everybody has seen is the movie Gravity, so that's their idea of what space junk is. So the idea that space junk can be an accumulation of tiny little impacts from small debris, I’m sure, is something that not a lot of people would be aware of.

IO

Yes, I think what we’re trying to do is to create a kind of visual accessibility to something that is so far away – how we interact with satellites and space debris that are very remote. Earlier, Yun Teng mentioned the analogy of the elephant you used in your book. The numbers around how much space debris is out there is often incomprehensible. But we love this metaphor because it's so accessible, and one can easily understand how large and heavy an elephant is, and imagine  a parade  of elephants marching around Earth.

AG

It was a quick visual entrée for people to understand. The other analogy I sometimes use is comparing space junk to plankton – incredibly huge numbers, everywhere in the ocean, and with a lot of diversity in forms. I was also thinking that a photograph taken of the night sky is almost like a slide under the microscope, with the plankton or micro-organisms frozen in a moment in time. I think we're coming back to the problem of bridging the gap. It's interesting what kind of things resonate with people, isn't it? I think with elephants, I suppose you could say from the tiniest kid to the biggest adult, everybody has a sense of how big an elephant is.

YT

I have another question about your perspective on heritage. In our conversations, we've spoken with people working in various areas, such as in the space industry, on policy levels, and within scientific research, but I don't think anyone else is looking at it from a heritage angle. What really struck me is your approach to space archaeology and cultural heritage. Previously, you mentioned this phrase “do as much as necessary and as little as possible”. Who decides what is junk and its heritage value? What are the parameters of space heritage significance, and how do parameters in traditional archaeology transfer onto space archaeology?

AG

Talking about the heritage significance of some of these objects is a way to form bonds with people and to bring out a sense of attachment. Because, again, when you say ‘space junk’, the assumption is that it is all useless. Yet when you say to people, “think about the significance of this spacecraft”, it gives them a point of understanding of what it is. It's not just a useless lump of aluminium, it's actually something that was made by people for a particular reason; it had a purpose, and that means something. So I think it's a way of differentiating things amongst the huge pile of everything that we call debris. The other aspect is that you can reclassify it. Say if something has heritage significance, it has a social purpose, so it's not technically junk anymore. Even if  it's something distant in space, if it's meaningful to a certain community, then it's not technically junk because it's doing something. The thing with heritage is that people generally assume heritage has to be something old. So you know, this stuff isn't old enough. Or it has to be something beautiful. Most people wouldn’t think of this stuff as beautiful, although we probably do.

These parameters are not subjective – they are qualitative, and that’s a huge difference. The phrase “do as much as necessary and as little as possible” comes from the Burra Charter (1979). It has very clear sets of principles for how you would assess heritage significance. This flummoxes engineers – when I have conversations with them, we talk about how cultural heritage significance isn’t static as it can change as people's values change and as events happen. It flummoxes engineers because they want to fix it in time.

So in the Burra Charter, if you're going to follow a process to capture the nature of the significance of something, the five criteria are: historic, scientific, aesthetic, social, and spiritual. Historic significance is obvious. Was it associated with famous people or events? The scientific significance of the spacecraft (although some of them are not doing science, of course) is not always about the science that was done, but also what you can learn from something. If that object didn’t exist, what would you no longer be able to find out? Or what we call “representativeness” – are there a million of these things, or only one? It could be the most common thing on Earth, but if there's only one of it left, then it's got a much higher scientific significance than it would if there were a million. Next, the important one is its social significance. We've been talking about how people become attached to things. A piece of space junk can have high social significance if it’s something that people care about - this can often be for nationalistic reasons. There’s a bit of overlap with spiritual significance, which is about belief. Often specifically religious or spiritual belief, but not necessarily. It’s something I've not really looked into so much, but I suspect with the Starlink mega-constellations, the approach that people who invest so much emotion into anything that Elon Musk puts into space is almost spiritual.

So you can assess and make a case for what kind of significance everything has in these five categories. You can then go further and say, “Well, is it significant at a local level? A regional level? A national level, a hemisphere or continent-wide level? Or a global level?” If it's of global significance, you're entering into World Heritage territory. The main criteria for World Heritage is “outstanding universal value”. However, none of this space junk can have World Heritage significance because it's moving. You're not allowed to have moving things on the World Heritage List, and they have to be on Earth. Somebody could possibly make a test case to get a satellite onto the World Heritage List, but it would be very difficult, perhaps just for a hypothetical situation. Thus, you have all of these ways of saying, “Well, is this thing very significant, or not very significant?”

In our situation, if we're looking at Earth orbit, you have to then ask, “What are the risks? Does this orbital spacecraft provide a high collision risk for other spacecraft?” If it does, then you can say, well, it doesn't matter how culturally significant it is, the risks outweigh that. So if we can get rid of it, then that's justified. I suppose a lot of this is about: “What can you justify to future generations? Is your research and your logic robust enough?” So that someone else can turn around and say that this was all done properly and ethically, or that the justifications here weren't sufficient for the actions that were taken.

Interestingly, someone did a study some years back which found that the longer something has been in orbit, the lower the collision risk. Which kind of makes sense, it's almost a bit circular, because if it had been in a high orbit, a collision might already have happened, or if it was low enough, it might have already been pulled back in and wouldn't have stayed up. So the older the satellite is, the less risky it's likely to be. Some of that relates to the fact that people were testing out a lot of different orbits for different things in the early days, so some of these objects are not in heavily congested places. I think the other strand to this is that we know that the United States, China, and Russia are the biggest contributors to space debris. So there's a lot of countries with a small number of satellites compared to what the big ones are doing. If you were to get rid of that one satellite or that small number of satellites that belong to a particular country, you basically reduce the diversity in the ranks of space junk; if you get rid of junk from the smaller nations or smaller companies, you're making the dominant ones more dominant. From the heritage perspective, representing the whole spectrum of geographies, types of satellites, and purposes of satellites is actually important.

There's also another argument – no one's ever done this in space, but they have done it on Earth – the “use it or lose it” principle. If a nation had nothing in space – not even junk in space – at some point in the future, someone might make the argument: well, historically, you've never used space. So you can't make a case that you have a right to it now. That argument doesn't work in the present, but in the future, demonstrating that you have a presence in space could become critical to establishing that you have a right to use space. These sort of heritage considerations then become heavily political, and you might have reason for resisting any proposals that your junk might be removed. So these are the implications of heritage value.

IO

It’s interesting that we’re borrowing parameters from traditional land-based archaeology to be put in place for space archaeology; and that even though an object might have historic, aesthetic, scientific, social, and spiritual value, it’s all negated because it's at a high risk of collision. This reminds me of an article where you wrote about ‘heritage offset’ where, say, if you had to destroy a satellite and it had all these values, the offset might come into place where you then gather and curate associated documents around it—in a way, preserving a ghost of the object, or its negative imprint. Could you talk a bit more about this? For most of the satellites that are out in space, whether they are junk or relics or artefacts, due to the inaccessibility of its environment, we would never get its original physical form back. It would either be destroyed through re-entry, or it would stay up there in orbit, far away from us. So this idea of creating something by association is very interesting.

AG

There's lots of people who say, let's go and get this historic satellite and bring it back and put it in a museum. That's the first idea people generally have about heritage management. In fact, the UK was proposing to try and catch their Prospero satellite and bring it back and put it in a museum, except they did say that they couldn't guarantee it would survive the process of coming back. But yes, the offset idea. It's not a substitute for the real thing, but you often have prototypes, models, and parts of things. So it's a little bit like the Chauvet cave where they have a complete replica that is preserved. Studies have shown that if people are not aware that they're looking at a copy, they would have the same kind of emotional reaction. If they don't know it's not authentic, they would be absolutely fine with it and have the same experience with the object. Some people compare this to Walter Benjamin's idea of the ‘aura’.

But I think the idea that you're piecing together a kind of a ghost by its absence – I think that's really powerful. You’re discerning the materials, the shape, and the effect of the physical presence by proxy, by having words or photographs which describe what it looks like instead of the actual thing. Plans, circuit diagrams and those kinds of things that are part of the ecosystem of the object, but not the object itself. I think that's quite a powerful idea. It’s almost like the residues or the leftover parts, which are often scattered in all kinds of places. People don't necessarily think about them or know where they are. But if you deliberately set out to collect them together as part of that process, you're in a way manifesting the ghost. With the heritage offset, it also preserves its scientific significance to a degree, because you would be able to access the research at a point when you can't necessarily access the actual object. I guess your point is, it's the process of curating that creates the actual ghost, so I really like that.

IO

When I was reading about your notion of the offset, it reminded me of this observation about the difference between fieldwork and lab work. In fieldwork, you're out there physically interacting with the sample or the object that you're working with; as opposed to lab work, where you understand the object or the artefact computationally in a remote sense. In both cases, there’s still an intimacy or a proximity to what you're studying. I think the idea of this ghost and imprint shows that there is still some sort of interaction or intimacy with the artefact even without its physical presence.

AG

Intimacy is a not-often-spoken-about aspect of archaeological work. It’s easy to say being in the field is great, you’re out in the environment, as opposed to sitting in the lab which students often say is boring. Yet there’s a kind of the relationship you develop to those objects because you're touching and handling them in intimate and physical ways, when you have to pick them up and take the measurements and so on. I think that is exactly the word to describe it. And I think it's not a word that people would often say about spacecraft. But it's interesting when you prod engineers hard enough, they will sometimes come out with some kind of statement that indicates they feel it too — they have an emotional, intimate relationship with the object they've been working on for so long. I suppose, then, that raises the question: when an object is absent or destroyed, what are their feelings about that, and how important do all of those residues become? I suppose you've got the difference between the highly curated objects that are in the museum or collections context, and the random ones that nobody's assembled or catalogued yet, but are still out there in people's houses and garages.

One of my favourite examples is the Australis-OSCAR 5 team. Australis-OSCAR 5 was designed and built by students from Melbourne University in the 1960s, and it was Australia's second home-built satellite. It was nearly the first, and I've been interested in it for a long time. One day, I was doing a radio interview about space junk in general. I went back to my office and I got a phone call from one of the Australis-OSCAR 5 team members. He had been about to recycle all of his paperwork to do with the design of the satellite, and he heard me on the radio and thought, “Oh, she might be interested.” So he rang me up and said, “Do you want this stuff?” and I went, “Of course I want it.” What was really interesting is that he'd never really told his family much about his work on this satellite. Anyway, he was coming to Adelaide and we arranged to meet up. His family came too, and I think seeing how interested I was made them see a new value in this strange thing their father and husband had done. But yeah, in terms of our relationship with stuff, he kept all this stuff since the 1960s, so it was kind of important to him.

IO

I think this is similar to what you were saying before, about the very loose definition between junk and not-junk. Especially with the choice of the term “space junk”, because that implies it is useless. For us, we were very deliberate with our choice of the word – we try not to use the word “space junk” when we talk about the project, but instead use the word “debris”. We are interested in talking about the destructive and violent nature of debris as a product of a collision or fragmentation event.

When you were talking about the different parameters of what makes artefacts valuable, such as heritage or spiritual significance, it made me wonder whether we should start to expand the terms we use. Instead of ‘space junk’ or ‘space debris’, we should, perhaps, start calling them ‘space relics’, or something along that line. I’m wondering in your work, do you try to extend the terms that you use and the definitions in different contexts?

AG

In my book, I discuss the different cultural meanings of discarded things, and the difference between a satellite being alive and being dead. So yes, I think there's a lot of interesting definitional conversations around this. This led me to another thought about relics. So objects like Skylab end up being treated as relics. The bits of Skylab on Earth have some kind of attribution of a semi-magical quality – it’s almost as if by owning and touching it, you partake of that quality. Another comparison is regarding the wood of the True Cross. The wood of the actual cross that Jesus was crucified on appeared as relics in thousands of churches across Europe. John Calvin famously said that if you put all of the pieces of the wood of the True Cross together, you'd have a whole ship, not just one cross. I think this applies very well to what happened to Skylab, in the sense that all those bits became imbued with this sort of otherworldly quality that people were keen to partake in, to the degree where they faked bits of it. I think the relic idea is interesting – people definitely don't think of space debris as space age relics. So what gets to be relics? It’s pretty selective which things get given that level of significance. Once it's back on Earth, it suddenly becomes collectible.