Orbital debris will continue to accumulate even if all satellite launches were halted immediately, according to a report prepared for the European Parliament's Committee on Industry, Research and Energy (ITRE). The document, authored by Valentina Richard Romei and dated September 2026, warns that collisions between objects already in orbit generate new fragments, which in turn cause further collisions. This dynamic makes an increase in debris inevitable, especially in low Earth orbit (LEO), even without additional satellites.
The report estimates that there are approximately 54,000 objects larger than 10 centimetres, 1.2 million between 1 and 10 centimetres, and about 140 million fragments between 1 millimetre and 1 centimetre. Their combined mass exceeds 17,000 tonnes. However, only 46,650 of these objects are catalogued and regularly tracked by space surveillance networks. The rest are known only through statistical estimates, complicating collision predictions and decisions on avoidance manoeuvres.
Since 1957, about 27,490 satellites have been launched. Around 69% remain in space, but only 58% are functional. Over the past decade, the total number of objects in orbit has multiplied by 2.43, according to European Space Agency data cited in the report. The main driver is the proliferation of communications megaconstellations in LEO, with Starlink alone accounting for roughly two-thirds of active satellites. The report attributes this surge to cheaper launches and increasingly smaller satellites.
The distribution of debris is highly uneven. LEO contains 25,060 catalogued objects, compared to 1,303 in medium Earth orbit and 961 in geostationary orbit. Debris makes up 37% of objects in LEO, versus 10% in geostationary orbit. This difference has a physical explanation: in LEO, atmospheric drag eventually causes debris to fall, though the process can take years. In geostationary orbit, at about 36,000 kilometres, friction is negligible, and objects can remain indefinitely unless moved to a graveyard orbit.
The worst-case scenario is the Kessler syndrome, formulated in 1978 by NASA physicists Donald Kessler and Burton Cour-Palais. It describes a chain reaction of collisions that multiplies debris and could render certain orbits unusable, particularly in the most populated areas of LEO. Typical relative speeds in LEO are around 10 kilometres per second. At that velocity, a fragment just 1 millimetre across can damage a satellite's systems, and one larger than 1 centimetre can cause partial or total destruction. The most cited precedent is the 2009 collision between the US commercial satellite Iridium and the Russian Kosmos-2251 at an altitude of about 800 kilometres. It was the first accidental crash between two intact satellites and generated more than 2,000 trackable fragments, many of which will remain in orbit for decades.
The economic impact is significant. The OECD estimates that a Kessler scenario would cause global losses of around €165 billion. An impact assessment of the proposed Space Law puts the cost higher: losing access to space would equate to 2.56% of global GDP. Even without reaching that extreme, avoidance manoeuvres consume fuel and shorten mission lifetimes. Their number is expected to increase 2.5-fold between 2019 and 2059, and shielding and manoeuvres could account for 5% to 10% of a mission's cost. Europe has already felt the effects. In 2021, a Galileo navigation satellite was out of service for two weeks following a collision risk alert. This is particularly relevant because approximately 10% of the EU's GDP depends on satellite navigation.
Uncontrolled re-entries are also a concern. Most objects disintegrate in the atmosphere, but some fragments reach the surface. The usual threshold is a casualty probability of 1 in 10,000 per re-entry, though the aggregate risk is growing: by 2030, it could reach 0.1 casualties per year. These re-entries can disrupt air and maritime traffic, and the report cites forecasts that the annual probability of an aircraft being struck could reach 1 in 1,000. Added to this are pollution from toxic or radioactive materials and the release of fine particles during burn-up.
Science also pays a price. Satellites and debris reflect sunlight and increase the brightness of the night sky by at least 10%, leave streaks in astronomical images, and interfere with radio astronomy. They also make it harder to detect potentially hazardous asteroids approaching Earth.
The European Space Surveillance and Tracking (EU SST) system, involving 19 member states, detected more than 30,000 conjunctions in 2025 — that is, dangerous approaches between objects. Of these, 4,500 were of high interest, more than 10 per day, and 81% occurred in low Earth orbit. Satellites registered in its avoidance service performed numerous manoeuvres, underscoring the growing operational burden.