The threat of space debris

A full-blown war in space is (hopefully) a long way off from being the primary threat to spaceborne assets. Putting aside for the moment the non-physical threats from cyber attacks, the most pressing concern is space debris. This is a clear and present risk today that would only be made worse by a shooting war in space at some indeterminate time in the future. As space gets busier, there is an increasing chance of accidental – or deliberate – collisions.

Pieces of man-made debris continue to travel at orbital speeds of tens of thousands of kilometres per hour, fast enough that one piece impacting a satellite would create thousands of new pieces. Debris that fails to quickly deorbit by falling to Earth has a chance of hitting another object and creating a new debris field, which then expands and could hit other objects, creating more  and more debris – a vicious circle known as the Kessler Syndrome [↗]. 

In a worst case scenario, the entirety of Earth’s orbit becomes inaccessible for anywhere from tens to hundreds of years due to this expanding shell of debris, smashing into anything we try to launch into space. The technology does not yet exist to deal with such an eventuality.

There are two main causes of space debris. The first is accidental break-ups or collisions, which create a cloud of debris that then poses a threat to other satellites. The second is weapons tests by nations that want to be able to target and destroy objects in orbit.

Accidental debris

Accidents do happen, but proper management can make them less likely. Collisions between satellites can be avoided through a proper space traffic management system that tracks and catalogues every piece of hardware currently in space. This information can then be disseminated to the owners and operators of these satellites, informing them of likely collision risks in advance so that the satellite can be instructed to adjust its orbit slightly.

In July 2021, Her Majesty’s (HM) Government announced [↗] a £1.2 million National Space Technology Programme to source proposals to aid with detection and tracking of space debris, better data management and integration and new debris removal technologies. With only £200,000 maximum per proposal, this is little more than a first step – but it is a step in the right direction.

The UK is also the largest contributor [↗] to the European Space Agency’s (ESA) Space Safety Programme, which helps develop new sensors and tools that assist in tracking orbital debris. So although a £1.2 million fund might seem small, it is by no means the extent of HM Government’s commitment to enhancing its space situational awareness. It also highlights another area that the UK is showing increasing leadership on – international collaboration and establishing norms and regulations for spaceflight.

This will be an essential cornerstone of mitigating the risks of the second major historical contributor to space debris propagation: military action in space.

Debris caused by military action

On the 15th November 2021, Russia carried out [↗] a direct-ascent anti-satellite (DA-ASAT) missile test targeting one of its old Tselina-D electronic intelligence (ELINT) satellites called Kosmos-1408 [↗]. The DA-ASAT impacted the defunct satellite, destroying it and scattering thousands of new pieces of space debris across several different orbital paths. 

The test was condemned by many other nations, including the United States (US) and the UK [↗], as well as by Japan and Australia [↗], while South Korea expressed concerns [↗] and European space industry leaders were ‘alarmed [↗]’. However, Russia is not the only country to have tested these sorts of weapons – in the past, the US, the People’s Republic of China (PRC) and India have all carried out similar tests. 

Of these, the US test took place at an altitude of 247 kilometres, the Indian at 300 kilometres, the Russian at 650 kilometres and the Chinese at 865 kilometres. Lower orbits generally mean debris re-enters Earth’s atmosphere faster due to atmospheric drag slowing them down and causing them to eventually burn up. Higher orbits tend to mean debris stays in orbit for longer periods. Objects from the 2007 Chinese test at 865 kilometres, for example, are still in orbit and continue to pose a risk [↗] to the International Space Station (ISS).

Here lies the problem – the height at which Russia destroyed the Kosmos-1408 satellite is roughly in line with the height at which the ISS orbits, meaning debris posed a risk [↗] to the international crew living and working aboard. This altitude is also the orbit – Low Earth Orbit (LEO) – that has seen the largest increase in satellite numbers over the past decade. 

While the US does not recognise outer space as a global commons, there are arguments that it should be viewed as such. Due to the nature of the risk from space debris, a solution would require international cooperation from every nation and commercial entity involved in launching and operating satellites. This needs to include regulation against further ASAT tests, and failing that, regulation that precludes ASAT tests in orbits that pose a serious risk of creating lasting debris.

The UK is advancing this cause at the United Nations (UN), with the UN First Committee in November voting 163 For, 8 Against and 9 Abstentions [↗] in favour of forming a new working group [↗] with the remit to:

1. Take stock of the existing international legal and other normative frameworks concerning threats arising from State behaviours with respect to outer space; 
2. Consider current and future threats by States to space systems, and actions, activities and omissions that could be considered irresponsible; 
3. Make recommendations on possible norms, rules and principles of responsible behaviours relating to threats by States to space systems, including, as appropriate, how they would contribute to the negotiation of legally binding instruments, including on the prevention of an arms race in outer space.

Russia, too, has sponsored [↗] UN measures that reaffirm [↗] the international commitments to the Conference on Disarmament (CD) as the primary multilateral disarmament negotiations forum and requests that it sets up a new working group to examine the prevention of an arms race in outer space. The UK has sought to create a new working group outside of the CD, pursuing a rules and norms based approach rather than a treaty-based approach favoured by the Russians and Chinese.

A new UN treaty on space activities will no doubt run into resistance – be it from the US, Russia or the PRC – but a lower level approach, as championed by the UK, may bear more fruit. HM Government should therefore push ahead with its efforts.

Richard Payne is the Communications Coordinator for the Council on Geostrategy. He holds an MSc in Global Cooperation and Security from the University of Birmingham.