Solving 'traffic jams' in space

The rapid increase in satellites and space junk will make low Earth orbit unusable unless companies and countries cooperate and share the data needed to manage this region of space.

Necessary coordination

A United Nations (UN) space traffic coordination workshop in late October identified the need for urgent action and called for a comprehensive common database of orbital objects as well as an international framework to track and manage them.

Data from US-based Slingshot Aerospace shows that more than 14,000 satellites, including about 3,500 inactive satellites, circle the globe in low Earth orbit. In addition, there are about 120 million pieces of debris from launches, collisions and wear and tear, of which only a few thousand are large enough to track.

"There is no time to hesitate in coordinating space traffic. We must do everything possible to ensure space safety, facilitate information sharing between operators (public and private) to avoid collisions," said Aarti Holla-Maini, director of the UN Office for Space Affairs, adding that low Earth orbit must be kept safe to prevent costly disruptions to global technology, navigation and scientific exploration.

However, there is no centralized system that all space-based nations can take advantage of, and even convincing them to adopt one is difficult. While some nations are willing to share data, others are concerned about security breaches, especially since satellites often have dual uses, including defense. Furthermore, businesses are keen to protect trade secrets.

Illustration of objects flying around the Earth. (Source: Getty Image).

Meanwhile, the situation is getting worse. A Chinese rocket stage exploded in August, sending thousands of pieces of debris into low Earth orbit. In June, a decommissioned Russian satellite exploded, sending thousands of pieces of debris into space, forcing astronauts on the International Space Station to take shelter for an hour.

Low Earth orbit is the most crowded area for man-made objects because it balances cost and distance, making it a prime target for the rapidly growing commercial space industry. The region also saw a 17% increase in close encounters per satellite over the past year, Slingshot data shows.

Tens of thousands more satellites are expected to enter orbit in the coming years, according to Montreal-based NorthStar Earth & Space, which estimates that the potential financial risk from collisions could be as high as $556 million over five years, based on a modeled scenario with a 3.13 percent annual collision probability and $111 million in annual losses.

'We are at a critical juncture in terms of creating regulations and structures in space to monitor and manage the growing congestion. With SpaceX's Starlink launching thousands of satellites a year, and China and others preparing to follow suit, we will soon be pushing the payload capacity of key orbits,' said NorthStar CEO Stewart Bain.

The final hurdle

Low Earth orbit is densely populated , with frequency bands like the one used for Starlink satellite internet service at altitudes of 540-570km. As of November 27, Starlink had 6,764 satellites in orbit, according to Jonathan Space Report. SpaceX data shows that Starlink satellites performed nearly 50,000 collision avoidance maneuvers in the first half of 2024, double the previous six months.

The European Space Agency also said that in 2021, its maneuvers increased to three or four times per spacecraft compared to the previous average of one time.

LeoLabs data shows that the 800-900km band contains fewer satellites but 3,114 objects (active and inactive), rocket bodies and debris (20% of the total mass of objects in low Earth orbit), posing a significant collision risk. Defunct satellites add to the clutter by remaining in orbit until they either re-enter or burn up in Earth's atmosphere years later, or are sent to 'graveyard orbits' some 36,000km away.

Global cooperation is needed to develop enforceable rules similar to those used by the International Civil Aviation Organization for air traffic, industry experts told Reuters. Such an effort would involve using existing tools such as databases, telescopes, radar and other sensors to track objects while improving coverage, early detection and data accuracy.

However, geopolitical tensions and reluctance to share data with countries deemed unfriendly, as well as commercial concerns about protecting proprietary information and competitive advantage, remain significant barriers.

That leaves orbital operators to rely on informal or semi-formal methods of collision avoidance, such as using data from the US Space Force or groups like the Space Data Consortium. But this can come with issues like accountability and inconsistent data standards.

The top challenges to global cooperation on space objects are speed (it takes time to reach consensus) and trust, said Ms. Holla-Maini, director of the UN Office for Outer Space Affairs. Some countries simply cannot communicate with others on the issue, but the UN can facilitate the process.