A rubbish challenge: how do we dump space junk?

In the vast expanse of space around our planet, there is a growing concern that has been gaining attention in recent years: space junk. This refers to the millions of human-made objects, ranging from full satellites that have ceased operation to small bolts shed during spacecraft launches, that now orbit Earth. The presence of this space debris poses significant risks to both ground and space-based astronomy, impacts atmospheric science, and threatens our increasingly space-reliant society. To address this pressing issue, experts Katherine Courtney and Alice Gorman recently discussed the problem and the steps being taken to tackle it in a Physics World Live panel discussion in November 2025.

Katherine Courtney, who started her career in the telecoms industry before transitioning to the public sector and serving as the chief executive of the UK Space Agency, became acutely aware of the impact of space debris during her tenure. Now chair of the Global Network on Sustainability in Space (GNOSIS), an organization with over 1,000 members from research and industry across more than 45 countries, Courtney is dedicated to accelerating research and development efforts to combat issues like space debris. GNOSIS aims to foster collaboration and innovation in tackling these challenges. Courtney also mentors start-up companies working on solutions and engages with young people through outreach programs to educate them about the importance of addressing space debris.

Alice Gorman, known as "Dr. Space Junk," is a space archaeologist at Flinders University in Australia. She focuses not only on debris in Earth orbit but also on planetary landing sites, deep space probes, terrestrial rocket launch sites, and tracking stations. Gorman's research examines space junk in an environmental context, assessing its cultural value and the significance of preserving these objects. Her work highlights the need for a comprehensive approach to managing space debris, considering both its technical and cultural implications.

The issue of space junk is a complex one, requiring a multifaceted strategy to mitigate its impact. One approach is to develop technologies that can remove debris from orbit, such as robotic systems designed to capture and deorbit the objects. Another strategy involves designing satellites and spacecraft in a way that minimizes the creation of new debris. Additionally, international cooperation is crucial, as space debris poses a global threat. Establishing clear guidelines and regulations for space activities can help prevent the accumulation of more debris in the future.

The conversation between Courtney and Gorman underscores the urgent need for action in addressing space junk. As our reliance on space-based technologies continues to grow, so too does the risk posed by space debris. By fostering collaboration among researchers, industry, and policymakers, and by investing in innovative solutions, we can work towards a future where space is not only a source of inspiration but also a safer and more sustainable environment for all. The challenges ahead are significant, but with the right approach and commitment, we can mitigate the risks associated with space junk and ensure the long-term sustainability of our space activities.