Spacecraft orbiting Earth play a vital role in monitoring climate change, enabling global communication and navigation, and advancing scientific research. However, many of these orbits are becoming overcrowded and increasingly filled with hazardous debris from old satellites and rockets, posing a serious threat to the future of space operations.
To address this, the Inter-Agency Space Debris Coordination Committee (IADC) — which includes ESA as a member — introduced the Space Debris Mitigation Guidelines in 2002. These voluntary guidelines offer recommendations on how to design, operate, and retire space missions in ways that minimize the generation of new debris. They marked a significant advancement in protecting key orbital paths and have shaped ESA’s mitigation policies, national regulations, and technical standards for the past 20 years.
Since 2017, ESA’s Space Debris Office has released an annual Space Environment Report, providing a clear and comprehensive overview of global space activity. The report assesses how effectively current measures — including international efforts — are supporting the long-term sustainability of spaceflight.
ESA's key 2025 takeaways
- Earth’s orbital environment is a finite resource.
- Satellites that remain in their operational orbit at the end of their mission are at risk of fragmenting into dangerous clouds of debris that linger in orbit for many years.
- The number and scale of commercial satellite constellations in certain low-Earth orbits continue to increase year over year.
- Within certain heavily populated altitude bands the density of active objects is now the same order of magnitude as space debris.
- Intact satellites or rocket bodies are now re-entering the Earth atmosphere on average more than three times a day.
- Yet not enough satellites leave heavily congested orbits at the end of their lives, creating a collision risk.
- 2024 saw several major fragmentation events as well as many smaller ones, together adding thousands of new debris objects, underlining the need for prevention by implementing passivation and reduced orbit lifetime measures.
- The adherence to space debris mitigation standards is slowly improving over the years, especially in the commercial sector, but it is not enough to stop the increase of the number and amount of space debris.
- Even without any additional launches, the number of space debris would keep growing, because fragmentation events add new debris objects faster than debris can naturally re-enter the atmosphere.
- To prevent this runaway chain reaction, known as Kessler syndrome, from escalating and making certain orbits unusable, active debris removal is required.
Read the original article and ESA's Space Environment Report 2025 here.
