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While the US government makes superficial changes to orbital debris mitigation guidelines, ESA is funding a mission to demonstrate the ability to deorbit debris. (credit: ESA)

The United States is losing its leadership role in the fight against orbital debris

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After more than a year of effort, the Trump Administration released an update to the US Government Orbital Debris Mitigation Standard Practices in December 2019. The Standard Practices define the standards for minimizing the creation of orbital debris and generally apply to all US government space missions and establish the foundation for rulemaking that applies to commercial space activities licensed by the US government. The updated Standard Practices are a key part of demonstrating how the United States fulfills its national space policy goal of strengthening the safety and sustainability of space activities and establishing a benchmark for other countries to follow.

Much has changed in the space world since 2001, and not entirely for the better.

They fall far short of that mark. The updated Standard Practices represent a minor improvement that fails to consider the magnitude of the changes that have occurred in the space domain over the last two decades, let alone what will happen over the next two decades, and lack the strengthened enforcement necessary to ensure compliance. They are also symbolic of an overall American position on orbital debris that seems to be more rhetoric than substance.

The first version of the Standard Practices was published in 2001 and was a landmark event in US space policy. For the first time, the entire US government agreed on a set of practices to limit the creation of space debris during normal space operations, limiting the sources of accidental explosions, avoiding collisions, and ensuring safe post-mission disposal of satellites. The Standard Practices adopted by the US government in 2001 became the foundation of the international debris mitigation standards that were agreed to by multiple national space agencies in 2007, endorsed by the United Nations in 2008, and increasingly implemented by spacefaring countries today.

Much has changed in the space world since 2001, and not entirely for the better. In 2001, there were only about 800 operational satellites and perhaps 10,000 pieces of orbital debris larger than ten centimeters that could utterly destroy a satellite in a collision. Today, there are more than 2,200 operational satellites, an estimated 22,300 pieces of orbital debris larger than ten centimeters, and nearly one million pieces of orbital debris bigger than one centimeter than could seriously damage a spacecraft. Commercial companies also have announced plans to launch tens of thousands of new satellites over the next decade and operate them in large constellations of hundreds to thousands each, along with swarms of increasingly smaller satellites, some no bigger than a credit card, that are more difficult to track and identify.

Accordingly, many stakeholders both outside and inside the US government expected the updated Standard Practices to deal with these new challenges. The biggest push was to tighten the so-called “25-year rule”, which says that you should ensure your satellite and any debris from its launch don’t remain on orbit for more than 25 years after its mission ends. Many scientists and satellite operators have called for that blanket timeline to be modified or reduced, particularly for satellites with missions of only a few months or orbiting in heavily congested regions. There was also a push to set a reliability metric for post-mission disposal mechanisms, particularly for large constellations where even a 10% failure rate across thousands of satellites could be disastrous. The original Standard Practices were also silent on the issue of remediation—actively removing existing debris from orbit—and contained no measurable metrics for enforcement.

Why did the Standard Practices fall short, given the public rhetoric from the US government about being a leader in mitigating the threat of orbital debris?

The updated Standard Practices published by the Trump Administration passed on most of those issues. Aside from adding a preamble, the content of the practices remained mostly unchanged from 2001. The main change was to add in some metrics, which are an improvement as they establish quantifiable goals to be met. However, the updated Standard Practices keep the blanket 25-year rule, including for very small or short-lived satellites, and hold satellites in large constellations to the same reliability metric as standalone satellites. They suggest constellations should strive for more reliability and very small satellites should be in orbit for as short a time as possible, but do not make those requirements.

Finally, the updated Standard Practices do not establish a clear prioritization for different post-mission disposal methods or the criteria by which less desirable disposal methods could be used. Although they say direct reentry is preferred, it is not emphasized and there is little to stop a government or commercial operator from choosing a cheaper or easier method, even if it could mean more cost and risk for other satellite operators down the road.

NASA has emphasized, correctly, that greater enforcement of the existing 25-year rule is critical to mitigating orbital debris. That finding is reinforced by a study done by the European Space Agency that found large constellations need better than 90% compliance with the 25-year rule to avoid a significant impact on the space environment. Current compliance for existing satellites is around 60% and shows only a slight upward trend. So yes, there is an urgent need to increase enforcement of the current 25-year rule. However, delaying any tightening of that timeline, even for specific circumstances, until near-perfect enforcement is reached seems shortsighted. Moreover, the Standard Practices do not address strengthening enforcement and compliance at all, which also seems like a significant oversight for such a critical measure.

Why did the Standard Practices fall short, given the public rhetoric from the US government about being a leader in mitigating the threat of orbital debris? The outcome of the interagency process often turns on the interests and positions of the agencies and departments involved, and that was likely the case here. During the process of updating the Standard Practices, several departments and agencies were indeed pushing for a much stronger set of standards, but other agencies resisted. Reports have suggested that NASA, which led the process, was one of the strongest opponents of tightening the standards, particularly the 25-year rule. Dr. J.-C. Liou, NASA’s Chief Scientist for Orbital Debris, has publicly said that their modeling did not show a significant decrease in the growth of the orbital debris population as a result of a shorter rule, and that a shorter rule would “incur additional costs for satellite operators.” Nonetheless, a growing number of satellite operators, through groups such as the Space Safety Coalition, have made statements and pledges calling for increased reliability in large constellations and shorter end-of-life deorbit timelines for certain mission types. These operators recognize the long-term value of orbital safety and sustainability is worth near-term mission cost impacts.

One wonders if winning a war in space in the short-term takes priority over minimizing orbital debris, even if the long-term costs for everyone, including the national security community, are huge.

NASA and the Department of Defense (DOD) are themselves major satellite operators and would bear some of the costs of a tighter disposal rule. Both NASA and the DOD have utilized waivers over the last 20 years to exempt a significant number of their own satellite missions from the 2001 Standard Practices. Most often this was done because the satellites were launched or designed before the 2001 Standard Practices came into force and making changes to comply with them would have cost too much money or would have too much of an impact on the mission. In a few cases, the decision was made to use the remaining fuel to extend the satellite’s life instead of disposing of it because the mission was deemed too important to end, such as with NASA’s Tropical Rainfall Measuring Mission. The waivers continued until very recently: 2017 was the first year that the DOD did not request a waiver. [After publication, the author found that DOD did request two waivers in 2017 and one in 2018.] Moreover, several Centaur upper stages from DOD launches that received waivers have recently exploded in orbit, creating significant amounts of orbital debris.

It’s also important to note the limits of the modeling NASA used to inform their position. The modeling focused solely on determining the long-term growth in the orbital debris population over the next 200 years as a result of launches and on-orbit collisions. It did not look at what the cost will be to detect those debris, predict potential collisions, and notify satellite operators. Nor does it include the costs operators face in dealing with a rapid increase in close approaches they will need to constantly deal with, including expending fuel to avoid potential collisions. That’s partly because the space situational awareness and tracking mission is not the responsibility of NASA (it currently rests with the DOD, although the Trump Administration wants to shift it to the Department of Commerce) and partly because these costs are difficult to model. The modeling also did not include the large constellations planned for deployment over the decade.

Comments from anonymous DOD officials suggest the national security space community was in favor of stricter standards, but my personal conversations with individuals in the national security community suggest that may not have been the consensus opinion across the organization. In addition to being wary of having to incur more costs for their own space missions, one wonders how the recent focus on warfighting in space impacted their position. Although senior military leadership publicly talk about avoiding war in space and limiting the creation of orbital debris, the rhetoric and policy direction from the White House and some members of Congress suggest a renewed political focus on developing offensive weapons to attack adversary satellites during a conflict. One wonders if winning the war in the short-term takes priority over minimizing orbital debris, even if the long-term costs for everyone, including the national security community, are huge. Others have suggested privately that perhaps a space battlefield cluttered with orbital debris might even be a military advantage for the United States as it can hide, maneuver, and fight in a congested environment more easily than its adversaries, although this is not anything DOD officials have stated publicly.

The most glaring failure of the updated Standard Practices and US policy on orbital debris in general is the continued failure to do anything about the existing orbital debris. In June 2010, the Obama Administration released an updated national space policy that directed NASA and the DOD to jointly pursue research and development of the technologies and techniques to remove existing orbital debris. Nearly a decade has passed and neither organization has shown any willingness to make that goal a reality. The space traffic management policy issued by the Trump Administration in June 2018 even appeared to take a step backwards: it noted that the US should pursue active debris removal but failed to provide any direction or goals to develop the capabilities, let alone budget the funding to do so.

With US leadership on orbital debris apparently diminishing, the hope now rests on other countries stepping up to the table. The good news is that a few are.

The unwillingness to address the current orbital debris situation seems at odds with the Trump Administration’s vision for the future of commercial space activities. Currently, the global space economy is valued at roughly $360 billion a year, with far greater indirect socioeconomic and national security benefits. The Trump Administration has touted that number may grow to a trillion dollars a year or more over the next few decades. But that growth will be mediated by the risks posed by orbital debris and the impact it has on business plans, revenue models, and investor confidence. Spending even $1 billion a year to reduce those risks, less than three tenths of one percent of the current value of space, seems like a wise investment, yet one the United States seems unwilling to make.

The Trump Administration has often argued that it is returning the United States to a leadership role in space, but on this issue they have moved in the opposite direction. These updated guidelines are part of a trend that suggests the United States isn’t willing to make strong legal commitments or monetary investment to ensuring the long-term sustainability of space, particularly compared to other priorities such as reorganizing US military space activities into the Space Force or bringing back US Space Command to develop battle plans for future space wars. Both of those efforts will cost the US taxpayer many billions of dollars in additional funding and involve thousands of people. In contrast, there are only a handful of dedicated civil servants working on space sustainability issues, and largely without many resources. The entire federal budget for space sustainability efforts is measured in the low tens of millions of dollars, and funding for critical areas like civil space situational awareness, space traffic management, and remediation is virtually nonexistent. Internationally, the US is willing to talk about voluntary measures, such as the recent United Nations Guidelines for the Long-Term Sustainability of Space Activities, but is unwilling to even entertain any binding legal commitments.

With US leadership on orbital debris apparently diminishing, the hope now rests on other countries stepping up to the table. The good news is that a few are. European leaders recently approved the next three-year budget for the European Space Agency, which includes funding for the first active debris removal mission, ClearSpace-1. The mission funds a consortium led by a Swiss company of the same name to remove a relatively small upper stage adapter ring from low Earth orbit. While this will not make a meaningful dent in the orbital debris hazard by itself, the mission will help prove out the technology and retire policy and legal risks with funding future removal missions. Japan has also significantly increased its focus on orbital debris mitigation and removal, with the City of Tokyo recently awarding the Japanese company Astroscale funding to begin developing a commercial debris removal service, while the Japanese space agency JAXA is partnering with Astroscale for a future debris removal mission.

Even with other countries stepping up, the United States will still need to play a significant role in cleaning up orbital debris. The United States is responsible for roughly 30% of the existing orbital debris, including the two dead satellites that nearly collided over Pittsburgh in late January (see “Will we hit the snooze button on an orbital debris wakeup call?”, The Space Review, February 17, 2020). That responsibility could translate into economic liability should one of those pieces of US-registered orbital debris create damage to another satellite on orbit. On top of potential direct damages, the growing risk posed by orbital debris will increase operational costs to satellite operators and could dampen investment and innovation.

Congress will need to fund these efforts appropriately, at perhaps a billion dollars a year or more. But that cost should be seen as an investment that will likely pay dividends across the breadth of space activities and benefits into the future.

That said, there are still steps the United States can and should take to regain their leadership role. The first step would be for Congress to provide a civil agency the necessary authorities and budget to assume the civil space situational awareness (SSA) mission and begin developing a space traffic management (STM) regime. Both are a necessary part of improving our knowledge about orbital debris and laying the foundation for dealing with it. To overcome the bureaucratic inertia holding back process on remediation, Congress should also designate an agency or department with responsibility for space environmental management, including orbital debris remediation. That agency or department should be charged with developing a strategy for creating the capability to actively remove orbital debris and other capabilities necessary to reduce risks posed by the space environment.

The federal agency charges with these responsibilities should explore how the US government can leverage private sector technologies and work with other countries to develop guidelines for conducting active debris removal safely and transparently. And yes, Congress will also need to fund these efforts appropriately, at perhaps a billion dollars a year or more. But while significant, that cost should be seen as an investment that will likely pay dividends across the breadth of space activities and benefits into the future.

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