Insight - Catalyzing Remediation of Large Space Debris

Tuesday, March 19, 2024

By Chief Program Officer Dr. Brian Weeden

Over the last several decades, there has been growing awareness and increased alarm in the space community and the general public about the risk posed by the buildup of orbital debris. Among the first to sound the warning were NASA scientists Don Kessler and Burton Cour-Palais, who described the possibility of a cascading series of collisions between space objects in their landmark 1978 paper. At the time, the worry was that at some point this phenomenon, later dubbed the Kessler Syndrome, would create enough human-generated space debris that it would pose more of a risk to active satellites than the naturally occurring space debris. 

Today, the situation is perhaps even worse than originally imagined. There are currently more than 9,500 active satellites orbiting the Earth, more than half of which are from the Starlink constellation (operating between 520 and 570 km altitude) and the OneWeb constellation (operating near 1200 km altitude). In addition, there are at least 36,000 cataloged pieces of debris larger than 10 cm in size and millions more smaller untracked pieces. Satellite operators are increasingly having to spend time and resources designing their satellites to survive in this congested environment and actively working to avoid potential collisions. The number of extremely close near misses of collisions between large debris objects that could create a catastrophic collision is increasing.

Efforts to solve this problem have been focused in three areas: orbital debris mitigation (reducing the creation of new debris during space activities), space traffic management (STM,  policies and processes to avoid collisions between active satellites), and active debris removal (ADR, remediation of existing debris from orbit). Orbital debris mitigation has seen the most success, with the development of international standards that are being implemented by a growing number of countries. Space traffic management has also been a significant area of focus over the last several years in several countries and within the United Nations.

It is the third area, ADR, where efforts by governments have been lacking. Since 2010, there has been a general scientific consensus that the world will need to remove 5-10 of the most massive space debris objects per year to avoid a worsening Kessler Syndrome. But translating that scientific conclusion into real-world action has proven difficult. The United States has done multiple studies and funded some early-stage concept work but has not announced a formal ADR demonstration program. China quietly removed one of its dead BeiDou satellites from geostationary orbit in December 2021 but has not made any public announcements about that operation or future follow-ons. Japan, the United Kingdom, and Europe have announced programs to demonstrate the removal of relatively small pieces of their own debris. No country has pledged to remove the very large objects that are the biggest source of future orbital debris. 

This situation prompted SWF to partner with LeoLabs and hold the Orbital Debris Remediation Summit in Queenstown, New Zealand, from February 20-22, 2024. The goal of the event was to bring together a focused group of international experts from industry, academia, and governments to discuss what could be done to catalyze serious efforts to remove large debris objects. Prior to the event, we released a joint statement outlining why this was a critical issue and identifying goals of the meeting. During the event itself, participants discussed how to resolve four categories of challenges: diplomatic, legal, programmatic, and economic. Overall, participants noted that while there has been a lot of talk about these issues over the last decade and many ideas have been floated, there was a lack of focus on developing those ideas into workable solutions that could help bridge the gap between awareness and action. And while technology demonstrations are a necessary first step, there also needs to be commitments for follow-on programs to begin removal of the most high-risk debris objects, especially those owned by the United States, Russia, and China.

While successful in its goals of highlighting the challenges and generating ideas for moving forward, the New Zealand event was just the beginning of our renewed dedication to this issue. In addition to a forthcoming public summary of our findings and recommendations, SWF will be holding additional discussions on this topic at our 6th Summit for Space Sustainability being held in Tokyo, Japan, July 11-12, 2024. Our goal is to use the Summit in Tokyo as a platform to further refine a strategy for making ADR real and encourage commitments from all the major spacefaring countries to take action. 

We hope this call to action will catalyze the space community into finally grappling with this problem and getting serious about ADR. Failure to do so puts at risk the hundreds of billions of dollars being invested every year in national security, commercial, and civil space programs around the world, as well as our continued ability to use space to improve the lives of everyone right here on Earth.