Low-Earth orbit is facing growing congestion as commercial satellite constellations expand, military satellite technology develops, and space debris multiplies due to increased traffic. The European Space Agency (ESA) has released its Space Environment Report 2026, produced by ESA’s Space Debris Office, which warns that Earth’s orbital environment is becoming increasingly crowded and that future projections show a worrying year-on-year deterioration with sharp rises in objects and collisions.
ESA Space Environment Report Warns of Congested Low-Earth Orbit and Rising Debris Risks
The report, based on data collected up to the end of 2025, aims to provide an annual overview of global space activity and evaluate whether international debris-mitigation measures are improving long-term spaceflight sustainability according to the findings. Among the key conclusions, ESA stated that an insufficient number of satellites are departing heavily congested orbits when their operational lives end, thereby increasing collision risks.
Data Show Millions of Debris Objects and Frequent Collision-Avoidance Maneuvers
According to data released by the European Space Agency, roughly 18,840 satellites out of all those ever launched remain in Earth orbit, with about 16,000 of them operational. Space surveillance networks routinely track approximately 46,650 man-made objects, which includes both satellites and rocket debris. Smaller fragments that are difficult for radar to track are significantly more numerous, with estimates placing debris pieces between 1 and 10 centimeters across at about 1.2 million, and pieces between 1 millimeter and 1 centimeter at roughly 140 million.
The congestion affects day-to-day operations. Starlink satellites performed over 355,000 collision-avoidance maneuvers between June of last year and May of this year, averaging more than 40 adjustments per satellite annually. ESA reported that more than three intact satellites or rocket bodies re-enter Earth’s atmosphere daily on average, while approximately ten new payloads are launched each day. The agency introduced a new metric in the 2026 report focused on on-ground casualty risk from re-entries, noting the probability remains low relative to everyday risks but has increased due to higher traffic levels.
Furthermore, ESA’s Space Environment Health Index determined that the long-term effect of current space activities worsened by an order of magnitude in a single year during 2025. The agency emphasized that active debris removal will be required to halt the growth in orbital objects driven by collisions creating additional debris, a phenomenon known as the Kessler syndrome.
