Introduction — A Crowded Sky and a Critical Moment
The global space economy surpassed $546 billion in 2024, driven by record launch rates and the rise of satellite mega-constellations. Yet this growth comes with an escalating cost: over 1.2 million pieces of orbital debris larger than 1 cm now orbit Earth, each capable of catastrophic damage.
As the number of satellites multiplies, the sustainability of the space environment has become one of the defining challenges of our time. What was once a niche concern for scientists is now a strategic priority for the entire satellite industry.
For SES, sustainability is more than compliance, it’s a commitment to innovation, safety, and long-term operational excellence. This philosophy was recently validated when SES’s O3b mPOWER constellation achieved the Platinum rating in the Space Sustainability Rating (SSR), making it only the second operator worldwide to do so.
Raising the Bar: What the Platinum Rating Means
Developed by the World Economic Forum, in collaboration with ESA (European Space Agency) and MIT (Massachusetts Institute of Technology), the SSR is the world’s first framework to quantify and compare the sustainability of space missions. It evaluates operators across six dimensions — from mission design and data sharing to end-of-life planning — assigning a rating from Bronze to Platinum.
“Adopting the Space Sustainability Rating was a way to innovate for sustainability and differentiate ourselves by applying industry best practices,” explains Charles Nzeussi, Specialist Product & Space Sustainability at SES.
This recognition positions SES among the global leaders in sustainable satellite operations, showing that performance and responsibility can coexist.
Medium Earth Orbit: The Sustainable Frontier
While most mega-constellations are being deployed in Low Earth Orbit (LEO) — a region increasingly crowded, SES chose Medium Earth Orbit (MEO) for O3b mPOWER. The decision was both technical and strategic with a spin-off on sustainability.
“The choice of MEO was deliberate and strategic,” notes Luana Capus, Engineer Flight Dynamics at SES. “It allows us to deliver global connectivity with far fewer satellites, reducing launch needs, collision risk, and overall orbital footprint.”
Operating in MEO, satellites can cover wider geographical areas and maintain longer operational lifespans. This architectural approach enables O3b mPOWER to provide global coverage with a smaller constellation size.
Designing for the Future: Sustainability-by-Design
The O3b mPOWER constellation was evaluated across 65 sustainability parameters, covering design, operation, and end-of-life management. Future iterations, says Capus, will go further:
“Future satellites could integrate features to facilitate tracking or potential servicing, such as visual markers or grasp fixtures, in line with emerging sustainability standards. For O3b mPOWER, end-of-life operations involve safely re-orbiting the satellites into a designated graveyard orbit above the operational region, ensuring compliance with best practices for space debris mitigation.”
This proactive approach aligns with the broader direction of international debris mitigation standards — including ESA’s updated ‘5-year rule’ for LEO missions — which reflect the industry’s growing focus on responsible end-of-life management across all orbital regimes.
Sharing Expertise, Shaping the Industry
Beyond technical innovation, SES is pushing for greater transparency and collaboration across the space community.
“SES has strong expertise in collision avoidance practices, which could be shared more widely to promote responsible operations in orbit,” says Nzeussi.
By sharing data and best practices through Space Situational Awareness (SSA) initiatives, SES helps build an “open by default” environment, one where space safety becomes a shared responsibility.
From Certification to Continuous Leadership
The Platinum rating is not the end of the journey, but the beginning of a new standard.
“Certifying O3b mPOWER is not the end — it marks the beginning of a journey,” Nzeussi concludes. “We aim to contribute to foster common ground across the industry to accelerate sustainability actions that drive efficiency, service quality, and new business opportunities.”
As SES’s former Chief Technology Officer, Milton Torres, emphasized:
“For four decades, SES has been at the forefront of promoting responsible practices and innovating new technologies that contribute to sustainable space operations.”
Conclusion — A Shared Orbit, A Shared Responsibility
Space is a shared environment: finite, fragile, and foundational to global connectivity and modern infrastructure.
The future of the space economy will depend on how effectively the industry embraces sustainability-by-design principles: intelligent architectures, transparent data sharing, and coordinated traffic management.
With O3b mPOWER, SES is demonstrating that the path to sustainability and the path to performance are one and the same — paving the way for an orbital ecosystem where innovation and responsibility thrive together.
Contributors:
- Charles Nzeussi – Specialist Product and Space Sustainability, SES
- Luana Capus – Engineer Flight Dynamics, SES
- Co-authored with Mateo Meo
References
🔹 Primary Sources (SES)
SES S.A. (2024). Why Sustainability Matters: SES O3b mPOWER Achieves Platinum Rating in Space Sustainability Rating. Internal press and corporate materials.
SES S.A. (2024). Spatial Sustainability: An SES Guide. Technical white paper on sustainable orbital architecture and debris mitigation practices.
Internal interviews and Q&A (October 2025):
Charles Nzeussi, Specialist Product & Space Sustainability, SES
Luana Capus, Engineer Flight Dynamics, SES
Torres, M. (2024). Statement from SES CTO on sustainable operations and innovation. SES Press Release.
🔹 Industry and Technical References
World Economic Forum (WEF). (2024). Space Sustainability Rating (SSR) — developed in collaboration with ESA, MIT, and University of Texas at Austin.
[Available at: https://spacesustainabilityrating.org]
European Space Agency (ESA). (2024). ESA Space Debris Office Annual Report. Data on debris mitigation and updates to the “5-year deorbit rule.”
OECD Space Forum. (2024). The Space Economy in Figures: Unlocking the Value of Space for Sustainable Development. Global space economy estimated at USD 546 billion in 2024.
NASA Orbital Debris Program Office (ODPO). (2024). Orbital Debris Quarterly News, Vol. 28.
Reporting over 1.2 million debris objects larger than 1 cm currently tracked in orbit.
United Nations Office for Outer Space Affairs (UNOOSA). (2023). Guidelines for the Long-term Sustainability of Outer Space Activities.
🔹 Contextual and Analytical Sources
Space Foundation. (2024). The Space Report, Q2 2024.
Notes a record 259 launches in 2024 — an average of one every 34 hours.
McKinsey & Company. (2023). The Race to Space Sustainability.
Analysis of ESG adoption and economic impact in the space sector.
Harvard Business Review. (2023). Sustainability in the New Space Economy.
Discussion on sustainability as a competitive advantage in emerging industries.
