Why should a private company make a business out of space debris removal?  Alternatively, can space debris removal be made into a viable business model?  This is one of those complicated questions that I recently saw reduced to a gross oversimplification in a news article.  There were a lot of issues with the article, and I don’t want to dwell on it, but I think the biggest problem was its underlying, unstated assumption that the only viable business case for space debris removal as a commercial service was if the government was the customer, or regulated private space industry into becoming customers.  The underlying argument of the article, therefore, is that there is no viable business model based on space debris removal.

First of all, it is worth framing the space debris problem in proper terms.  When most people talk to me about space debris, or about space in general, they convey the sense that space debris is a pervasive, consuming, imminent problem.  From the articles you might read on the topic, you’d think that space was just a giant landfill already, with functional satellites skulking slowly through the sludge.  This is not helped by artists’ renderings showing satellites piled up and surrounding Earth like a Dyson Sphere, or panicking declarations by astronomers about the stars becoming invisible, or melodramatic advertisements from the Space Force featuring satellites moving in real time to avoid impacts, or really bad movies about runaway collisions in space (I’m looking at you, Gravity).

Yes, space debris is a problem, but it’s not a today problem.  Space debris is the sort of thing that will become a significant problem if we don’t do anything about it in twenty five or fifty years.  This is not to say that it’s a problem that we should be ignoring, just because it’s not an imminent threat, but it is useful to reframe the problem in more realistic terms, with a little less sensationalism.  In a phrase, space is big.  Big in a sense that is almost incomprehensible.  I will try to put it into perspective.  The radius of the Earth is about 6378 kilometers.  That means the Earth’s surface area is some 511,185,932.5 km2 (511 million).  If we say that we have a low earth orbit (LEO) with an altitude of about 500 km, the surface area of that sphere would be 594,475,836.95 km2 (almost 600 million).  At medium earth orbit (MEO) altitudes of about 20,000 km, that surface area becomes 8,743,666,649.4 km2 (8.7 billion), more than ten times more surface area than the LEO orbit.  Geostationary (GEO) orbits have a distance from the center of the Earth of 42164 km, which gives a surface area of 22,340,530,070.42 km2 (22.3 billion).

Not all of that “surface area” will necessarily correspond to useful orbits, and it’s not like land area on the surface of the Earth – this is to give you an idea of just how big space is.  The average cross sectional area of a satellite in 1995 was about 10 square meters, and is probably much smaller today.  That one satellite in LEO would occupy 0.00000000168215% of the LEO “surface area,” 0.000000000114368% in MEO, and 0.0000000000447617% in GEO.  In other words, by surface area, there is room for ten billion satellites and less than twenty percent of these orbits would be filled.  We might not want to fill that entire surface area (unless we were building some kind of riff on a Dyson sphere), but the point is that space is almost unfathomably vast compared to the scales to which we are accustomed in terrestrial settings.  For reference, there are estimated to be a mere 900,000 manmade objects currently in all Earth orbits combined.

Furthermore, managing space debris is not as unregulated as the hyperbolized warnings would suggest.  In the US, NASA originated a requirement for most spacecraft to have a deorbit plan within 25 years of launch.  Spacecraft and other objects with orbital altitudes of less than a thousand kilometers will naturally deorbit due to atmospheric drag, and spacecraft in LEO will often use thrusters to lower their perigee in order to increase their drag over time, slowly lowering the orbit until the energy is sufficiently low that they burn up in the atmosphere.  Higher orbits will move from a mission orbit to a trash orbit or graveyard orbit when they reach their end of life, orbits that are currently considered of minimal usefulness.

While I think it is important to step back from the apocalyptic and sensationalistic messaging on the topic of space debris, it is a minor problem currently, and will eventually become a major problem in the decades to come if unmitigated.  Full mission lifecycle planning for spacecraft is helpful, but outside of low altitude orbits is more of a stopgap measure.  Even if we never find a use for the graveyard orbits, perturbations will over decades and longer migrate defunct spacecraft in those graveyard orbits into more perilous configurations.  Perhaps most perniciously, mission planning can do only so much to address the actual debris that is generated as part of many space missions: rocket bodies, discarded motors, used frangibolts, and other, disposable components that go along with the compromises necessary to get an object to space, and make it functional there.

As space debris becomes more of a problem for the users of space, the potential business case for space debris removal services improves.  If a company is concerned that their three hundred million dollar spacecraft is going to be hit by space debris, they very well might pay another company to “take out the trash,” just like businesses and individuals in terrestrial settings pay for trash and recycling companies to remove waste products from their vicinity.  The technical challenges are immense, but as the risks become greater, the economic case grows for solving those challenges.  Launching an armored satellite with current technology is prohibitively expensive, so space debris removal could be a cheaper and more technically feasible solution.

More intriguing to me is the case for repurposing the resources that we’ve been launching into space for the past half a century.  I have been advocating for the necessity of in situ resource utilization to further space access, exploitation, and exploration for many years, and graveyard orbits full of defunct spacecraft look to me like ribbons of raw materials spinning around the planet, with the costs of launch already paid for, and the very materials of interest conveniently packaged for use.  Rather than a space-debris-removal-as-a-service paradigm in which companies attempt to become the orbital version of Waste Management, paid by satellite operators to ensure the cleanliness of their orbits, I am intrigued by the potential economic viability of harvesting space debris for its raw materials to be used for in-space industry.  In this model, rather than selling space debris removal, the product would be new spacecraft, created by collecting space debris and using the resources contained therein.

Of course, the technological barriers to achieving such a capability are immense.  Resource processing in space has never been done before.  The velocities of the debris involved, and the disparate compositions, make capture and retrieval a daunting proposition.  So too does the amount of energy required to change all of those orbits in order to assemble the debris at some kind of processing station.  Either extremely complex automation or a manned industrial plant in space would need to be established in order to implement this idea.  Legal and cultural challenges exist to, regarding resource ownership of space debris, the complex imagery of such dual use technologies, and potential risks to operational spacecraft.  Any technology that would be capable of addressing space debris would also be able to do the same to operational satellites – in other words, space debris removal would have the twin capacity for being a devastatingly effective antisatellite weapon.

All of this is to say: there is a viable business case for space debris removal that does not invoke the government as a necessary regulator or even primary customer.  Implementing that model, however, is riddled by technical and human challenges that must first be addressed.  Fortunately, despite what media “experts” who probably think that HEO means High Earth Orbit say, we have time to develop those solutions before our orbits look like advanced “spacefills.”

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