The European Space Agency (ESA) has released its Space Environment Report 2026, warning that Earth’s orbital environment is becoming increasingly congested as commercial satellite constellations continue to expand.
The report, produced by ESA’s Space Debris Office, aims to provide an annual overview of global space activity and assess whether international debris-mitigation measures are improving the long-term sustainability of spaceflight. ESA said the 2026 report is based on data collected up to the end of 2025 and excludes projects still being prepared for launch.
Among its key findings, ESA said not enough satellites are leaving heavily congested orbits at the end of their operational lives, contributing to rising collision risk. It reported that more than three intact satellites or rocket bodies are re-entering Earth’s atmosphere each day on average, while around ten new payloads are launched daily.
ESA also pointed to changing constellation behaviour, including a trend of constellations shifting altitude significantly from year to year, and introduced a new metric in the 2026 report focused on the on-ground casualty risk of re-entries. ESA said the probability remains low relative to everyday risks, but has increased in recent years due to higher levels of traffic.
The agency said its future projections show a “worrying” year-on-year deterioration, with expected numbers of objects and collisions in low-Earth orbit rising sharply, even after shortening its projection horizon from 200 years to 100 years.
ESA’s Space Environment Health Index, designed to summarise long-term sustainability with a single figure, found that in 2025 the long-term effect of current space activities became an order of magnitude worse in one year, according to the report.
The agency said active debris removal will be needed to stop the growth in orbital objects driven by collisions creating additional debris, often described as the Kessler syndrome. It added that while some indicators suggest interest in and adherence to debris mitigation is increasing, efforts need to be faster, more consistent and more reliable to avoid passing escalating costs and constraints to future space users.