What is space debris and how close are we to cleaning it up?

Space debris is anything in orbit that no longer does a job: dead satellites, spent rocket stages, and the fragments left when they break apart. ESA says there has been more debris in orbit than working satellites ever since the space age began (ESA).

How much is up there

It depends on the size you count. ESA's model, from February 2026, estimates:

• 68,450 objects larger than 10 cm, including about 11,300 working satellites
• 1.5 million pieces from 1 to 10 cm
• 230 million pieces from 1 mm to 1 cm

Those figures come from ESA's 2026 Space Environment Report (ESA). They are model estimates, not counts.

Only the big pieces are tracked. The US Space Surveillance Network routinely tracks objects larger than about 10 cm. As of August 2026 it had catalogued more than 34,000 objects (NASA). ESA counts about 47,370 objects that tracking networks follow regularly (ESA DISCOS).

The small pieces matter because of their speed. In low Earth orbit, debris travels at 7 to 8 km a second, and it hits other objects at about 10 km a second on average (NASA). ESA calls anything larger than 1 cm "large enough to be capable of causing catastrophic damage" (ESA). The space station is the most heavily shielded spacecraft ever flown, and its critical parts can normally survive hits from debris up to 1 cm across (NASA). So the most dangerous pieces are between 1 and 10 cm. They are big enough to kill a satellite and too small to track routinely.

When a tracked object is predicted to pass close to the ISS with a collision chance above 1 in 10,000, the station moves. It has done so 41 times since 1999 (NASA).

How it got there

Most debris comes from things breaking apart. A few events made a lot of it at once:

• 2007. China destroyed its own Fengyun-1C weather satellite with a missile.
• 2009. The Iridium 33 and Cosmos 2251 satellites collided by accident. NASA says these two events significantly increased the amount of large debris in orbit (NASA).
• 2021. Russia destroyed its Cosmos 1408 satellite in a missile test. It created more than 1,500 pieces of trackable debris (Office of Space Commerce).
• 2024. A Chinese Long March 6A upper stage broke apart after launching the first Qianfan satellites, leaving more than 300 trackable pieces (Space.com). In October, the Intelsat 33e satellite broke up in geostationary orbit (CSI).

Accidents keep happening. Over the last two decades, about 9.8 accidental breakups have occurred every year (ESA report).

Why it keeps growing

In 2025 there were more than 300 launches, carrying over 4,000 new satellites. ESA says more than three intact satellites or rocket stages fall back into the atmosphere every day, while ten new ones go up (ESA).

The bigger worry is collisions making more debris. ESA calls this the Kessler syndrome: "the self-sustaining cycle of collisions creating fragments that trigger further collisions". It says that even if no new satellites were launched, the debris would keep increasing, "because fragmentation events generate debris faster than they can naturally reenter the atmosphere" (ESA).

The rules

In September 2022 the US Federal Communications Commission adopted a rule that satellites in low orbit must come down no later than five years after their mission ends (Via Satellite). It replaced a 25-year guideline (Payload).

In Europe, twelve countries signed ESA's Zero Debris Charter in May 2024. It aims to make space activity debris-neutral by 2030 (ESA). The European Commission proposed an EU Space Act with debris rules in June 2025, and member states are still negotiating it (E+H).

ESA now says rules alone won't fix it. "Prevention alone is no longer enough. Active debris removal must become part of the solution and soon" (ESA).

Tracking it

Governments run most tracking. NASA also uses ground radars to detect debris as small as a few millimetres and estimates the rest with models (NASA). In the US, the Commerce Department is building TraCSS, a civil system to warn satellite operators of close approaches. It is running on its 2026 budget, but the 2027 budget request would cut the office that runs it by about 80% (FedScoop).

Companies sell tracking too. These are in our directory:

• LeoLabs runs its own radar network and a commercial catalogue of objects in orbit (LeoLabs).
• Slingshot Aerospace runs optical sensors. The UK Space Agency uses it to track satellites and debris (Slingshot).
• Digantara in India is building MOSAIC, a system that detects objects moving above the country and separates satellites from stars and debris (India Today).
• OKAPI:Orbits in Germany sells collision-avoidance software. Tech.eu reported that SpaceX and Amazon use it (Tech.eu). It is also building the next version of MASTER, ESA's model of the debris environment (OKAPI:Orbits).

Removing it

Why it is hard. Debris was never designed to be caught. Astroscale says unprepared objects have none of the technology that makes docking possible (Astroscale). Many targets are large. The rocket stage ADRAS-J2 will try to catch is about 11 m long, 4 m wide and weighs around three tonnes (Isar Aerospace). Targets can change before you reach them. ClearSpace-1's first target, a payload adapter left by a Vega rocket in 2013, shed new fragments in August 2023 (ESA).

The spacecraft doing the catching can fail too. Katalyst launched its LINK robot in July 2026 to grab NASA's Swift telescope, a working satellite, and raise its orbit. An attitude-control problem sent LINK into a spin. It never captured Swift and re-entered on 25 September 2026 (Katalyst).

What has been tried. Every mission so far has practised on something easier than real debris:

• In 2018, the UK's RemoveDEBRIS caught a target with a net. The target was one it had carried up and released itself (ADS Group).
• In 2021, Astroscale's ELSA-d repeatedly caught its own client satellite with a magnet (Astroscale).
• In 2024, Astroscale's ADRAS-J flew within 15 m of a real abandoned Japanese rocket stage and photographed it, without touching it. It began deorbiting itself in March 2026 (Astroscale).

What comes next. Astroscale's ADRAS-J2 will try to capture that same rocket stage and bring it down. It is due to launch on Isar Aerospace's Spectrum between 2027 and 2028 (Isar Aerospace). Payload describes it as aiming to be "the first spacecraft to capture and remove a piece of large orbital debris" (Payload). Astroscale's ELSA-M will remove an end-of-life Eutelsat OneWeb satellite (Astroscale). That satellite was prepared to be caught, so it is easier than real debris (Astroscale).

ClearSpace was the original contractor for ESA's ClearSpace-1. In 2024 ESA handed the lead to a consortium under OHB. ClearSpace still runs the approach and capture (ESA). The target is now ESA's old PROBA-1 satellite, and launch is planned for 2029 (ESA). In October 2026 it signed a £61M contract with the UK Space Agency to remove two dead UK-registered satellites (ClearSpace).

Others are working on parts of the problem. Starfish Space has taken control of another company's spacecraft to practise a rendezvous in orbit (Ars Technica). Katalyst Space was picked by the US Defense Innovation Unit to plan the capture and deorbiting of Space Development Agency satellites that were never designed for servicing (Katalyst). Orbital Lasers in Japan is studying how to slow a tumbling object with a laser so it can be caught (Orbital Lasers).

The latest from each company

How close are we?

Tracking debris is a working business. Several companies sell it, and governments buy it.

Removing it is not, yet. As of November 2026, no mission has captured and removed a real piece of debris. ESA still describes ClearSpace-1 as "the first mission to remove a piece of space debris from orbit" (ESA).

What to watch

• ClearSpace's PRELUDE demonstration with ESA, targeting launch in 2027 (ClearSpace)
• Astroscale's ADRAS-J2, the first attempt to capture and remove a real rocket stage, between 2027 and 2028
• Astroscale's ELSA-M, removing a OneWeb satellite built to be caught
• ClearSpace-1 and the UK's debris removal mission, both aiming for 2029
• A French demonstration with Astroscale and Exotrail to deorbit a OneWeb satellite, between 2029 and 2030 (Astroscale)
• Whether the US funds TraCSS in 2027