Space: The Final Frontier of Waste?
Since the dawn of the space age in 1957, humans have successfully launched over 5,000 rockets into space and placed roughly 9,000 satellites in orbit. And as aerospace technology progresses, this number is increasing at an accelerating pace. In the last three years alone, we’ve launched over 1,600 objects into space for research, telecommunications, supplies to the International Space Station, and more.
Unfortunately, while a little over half of those 9,000 satellites we’ve deployed over the years are still in orbit, fewer than 2,000 remain functioning. The thousands of dead satellites that continue to revolve around Earth comprise a navigational minefield that poses a serious risk to existing and future space missions. Each time defunct satellites crash into each other, countless new bits of debris are created and must be factored into launch trajectories so that future missions can avoid them. To make matters worse, these collisions can cause an unstoppable snowball effect as debris fields grow to a critical mass and the risk of additional incidents increases exponentially (also known as the Kessler effect). The result has been a zero-gravity wasteland, an increasingly dense web of metal zooming around the Earth at high speeds and threatening the future of our last frontier just miles from where we stand, in a place where distance is measured in light years.
From a resource depletion perspective, orbital space can be thought of as an environment that is getting polluted by debris creation events. Though space does not exactly fit the conventional image of “the environment” or “nature” in this sense given there is no tangible medium that is being sullied, the very volume of orbital space itself can be thought of as a common resource that is being eroded by debris.
The problem with this pollution is that not all debris is trackable. While global space surveillance networks currently keep tabs on more than 22,000 individual pieces of debris, statistical models estimate that there are up to 130 million debris objects currently in orbit. This debris, traveling at many times the speed of sound, can cause devastating damage to equipment and spacecraft in orbit. In so-called “hypervelocity impacts”, even a 1 cm object (roughly the size of an M&M) can inflict mission-critical damage. A 10 cm, credit card-sized projectile will typically cause catastrophic disintegration of anything it hits.
So what can we do to stop this pollution and mitigate the risk of our next space mission getting decimated by a flying paper clip? Broadly speaking, we need to acknowledge the dangers of space debris and address the flaws in spacecraft design and space management protocols before the upper atmosphere gets too crowded. With new satellites and other instruments being launched into space almost daily, the risk of orbital collisions continues to grow.
Problem 1: Satellites are Generally Not Designed to be Recoverable
Most satellites and other space instruments are not designed to be reused due to the effects of the harsh environmental conditions in space, and are thus generally not worth recovering. Historically, most have taken one-way trips up and anything that comes back down and survives the return trip through the atmosphere takes up a final resting place at sea. Point Nemo (Latin for “no one”), an area in the Pacific Ocean stretching for millions of square miles that is farther from civilization than anywhere else on the planet, is perhaps the most popular place to crash-land space objects and is home to over 260 downed spacecraft ranging from small resupply vehicles to the 120-ton Soviet-era MIR space laboratory. While it’s obviously better for dead spacecraft to land in the middle of the ocean than, say, Manhattan, space junk in places like Point Nemo can exacerbate existing pollution problems by further contaminating the area. Already beset by plastic waste problems, Point Nemo’s once pristine environment is increasingly becoming a junkyard.
It’s not that reusability has never been on the minds of scientists working on space-faring missions. One of the most famous spacecraft in history, NASA’s Space Shuttle, was developed to be partially reusable. While its largest component, the external fuel tank, mostly burned up on reentry, the two boosters and the orbiter (the airplane-like vehicle which most people think of as the “shuttle”) were recovered after use and refurbished. More recently, companies like SpaceX and Blue Origin have developed, launched, and landed reusable rocket boosters, demonstrating feasible component recovery.
The issue is that, while rockets and other launch components are worth recovering to be used in subsequent missions, satellites and other orbital instruments don’t have much use beyond their operational life in space and are thus not worth the money and effort to retrieve. It costs much less, if anything, to simply let a dead satellite drop back down by itself and mostly burn up than to remove it from space intact for proper disposal or recycling. Consequently, most satellites in low Earth orbit are left in decaying orbits or slowed down with their last bit of propellant to fall back through the atmosphere and into the ocean. Satellites in higher orbits that are farther away from Earth undergo similar measures, albeit in the opposite direction, and are pushed even deeper into space to what are called “graveyard orbits” that place them out of the way of most active space instruments.
The primary benefit of these satellite removal strategies is that we can maintain a usable band of orbital space around the planet for active satellites and space missions. The cost is that these actions both contribute to pollution problems on the Earth’s surface and compound the risks of collision in outer orbital zones. Until we can find a way to methodically and cleanly remove nonoperational satellites from orbit, these problems will only grow.
Problem 2: No Standards for Managing Space Debris
Since supersonic debris in orbit has the potential to cause problems for space infrastructure and space missions, regulatory groups have taken some steps toward debris mitigation and management protocol establishment. Unfortunately, existing regulations are either unenforced or vague, so the growing population of private space tech companies, and even government space programs, has little incentive to follow them.
One of the more recent efforts at regulating space debris, primarily focused on the active orbital operations of satellites, is a set of global guidelines that was released in 2007 by the United Nations’ Office for Outer Space Affairs in coordination with NASA and the European Space Agency. For a document that was in the works for over a decade (a discussion on debris mitigation that was the impetus of this document was first held by the UN Committee on the Peaceful Uses of Outer Space in 1994), the publication contains surprisingly little helpful guidance. Most of it is common sense, from simply making best efforts at avoiding collisions in orbit to curtailing the intentional destruction of satellites in space. There is no mention of a system for accountability, and the document just encourages space programs to “voluntarily take measures” to implement the listed guidelines. As a result, these guidelines have only been followed in about 40% of space missions, according to Dr. Alice Gorman, a space archaeologist on the executive council of the Space Industry Association of Australia.
On the decommissioning side of the problem, there is also no global consensus on the best way to remove existing debris from orbit. Gorman contends that this stems from a single glaring issue: any mechanism able to remove dead satellites and other debris from space is, by definition, also a potential anti-satellite mechanism. This could be a hotbed of international incidents, from theft of military technology or other government secrets to sabotage and espionage. The accidental removal of an active orbiting satellite could easily be viewed as military aggression and lead to political conflict.
In terms of bringing satellites down to the surface, the process of splashdown decommissioning–when a satellite is brought out of orbit and crashed into the ocean–is a legally complicated issue given conflicts between standard practices of space law and marine law. What is conventionally referred to as “space law”, as established in 1967 with the Outer Space Treaty, dictates that splashdowns are perfectly legal and in fact necessary for the preservation of the resource of space. However, this framework neglects to address the detrimental consequences of polluting ocean environments with junked satellites, which could be seen as a violation of marine law. This mess of legal jurisdiction is yet another product of a lack of international effort in establishing proper regulations on space debris and will only get worse as more and more satellites reach the end of their life cycles.
Problem 3: Satellites Are Getting Smaller
As technology for communications equipment and spacecraft components progresses, the need for bulky and expensive satellites is diminishing. Many satellites today have small form factors and are classified as “CubeSats”, roughly the size of a small tissue box with a basic design that was first proposed in the late 1990s and inspired by the Beanie Baby toy craze of that time. While smaller sizes greatly increase operational efficiencies in rocket launches by decreasing payload weight, the proliferation of CubeSats and other small satellites in orbit can cause problematic congestion in orbit paths and lead to collisions.
One way in which this proliferation is beginning to manifest is so-called “mega-constellations”, projects that involve the deployment of hundreds, or even thousands, of small satellites into a grid around the Earth primarily to optimize communications networks. One such project, SpaceX’s Starlink satellite network, involves launching 12,000 satellites into low Earth orbit to beam high-speed internet around the world. Such a massive undertaking poses a serious risk of debris creation, and constant monitoring will be necessary to avoid collisions. Unfortunately, this is much easier said than done. SpaceX has already launched 60 of these satellites and lost communication with three of them just one month after launch. Though these satellites will likely burn up in the atmosphere as soon as their orbits decay enough for them to start falling, they could easily crash into other objects in orbit in the meantime. In addition, only 95% of the mass of these satellites will burn up upon reentry, which means that roughly 25 pounds of metal will rain down somewhere on the surface of the planet for each 500-pound satellite the company loses contact with.
The cost of getting these CubeSats into orbit is decreasing as well, with several companies developing cheaper launch technologies and processes. To achieve this, many of these innovations draw from ideas that were developed for ground transportation. For example, rocket launch startup Rocket Lab offers a “rideshare” service as the Uber/Lyft equivalent for satellite deployment. Aiming to offer monthly launch services, the company’s platform comes complete with a slick booking portal that offers a selection of payload sizes and launch windows. The company does also offer a dedicated launch service for presumably larger or more sensitive payloads, but the rideshare offering is what’s truly indicative of where the launch industry is heading — increasingly frequent launches bringing into orbit more and more satellites at once.
As these trends in satellite deployment progresses, it is becoming increasingly likely for crowded orbital space to yield catastrophic collisions. The rise of CubeSats and the ability to launch smaller, cheaper, and more satellites is great from a scientific research or infrastructure perspective, but continued implementation without proper debris mitigation and collision avoidance measures will quickly deplete our orbital space resources and pollute the space environment. In fact, scientists from NASA recently conducted a study that simulated how CubeSat deployment will impact low Earth orbit, and found that, over the course of a 200-year projection period, large-scale deployments of CubeSats would lead to a cumulative increase of more than 300% in the number of catastrophic collisions in orbit over baseline deployment projections. Even factoring in end-of-life recovery mechanisms for CubeSats that are deployed at altitudes higher than effective naturally decaying orbits, the number of catastrophic collisions still doubles. The study does not make any assumptions on the existence of separate clean-up or retrieval processes that may reduce the risk of collisions caused by existing debris, but the point is that no matter how we manage CubeSats after launch, it will become increasingly difficult to maintain a clean low Earth orbital space.
The Outlook
Right now, the global space-faring community is not aligned on standards to mitigate the deterioration and pollution of our planet’s orbital space. It’s somewhat understandable why space tech companies and government space programs haven’t made a coordinated effort to fix this, given how much value satellites and other space infrastructure have created for society. And after all, there’s so much space in space that we shouldn’t have to worry about these issues for a very long time…right?
The problem is, this isn’t something we can keep procrastinating on forever. Without taking action soon, we will be forced to be reactive instead of proactive and deal with irreversible pollution in an environment bigger than any other we have dealt with. The path to clean orbital space will not be easy, and we already have large-scale pollution problems on the ground to deal with as well, but we have a rare (and possibly final) opportunity to set a path of sustainability before we stray too far. Pollution in space may not currently be as big of an existential threat to humanity as climate change, global conflict, or other issues more visible and tangible to the average person, but it’s a problem that is theoretically unbounded and sets the precedent for how we as a species will take our next big evolutionary step forward. Particularly in our own orbital space, our upper atmosphere represents the gateway to future interplanetary and interstellar travel. If we can’t get it right here, how can we ever expect to sustainably colonize Mars and other planets?
From where we stand today, space is a frontier of many things — science, exploration, the human imagination, you name it. We need to do whatever we can to prevent it from becoming a frontier of waste.
