With hundreds of satellites launched every year, in-space collisions and the creation of fast-moving fragments of space debris – or ‘space junk’ – are becoming increasingly likely, threatening our continued human and technological presence in space.The Organisation for Economic Co-operation and Development (OECD) recently published its first report on the economic cost of space debris. Using research from numerous sources, including data and analysis from ESA’s Space Debris Office, it outlines the dangers ahead if we do not act, and what can be done to ensure our future in space.
Here, we summarise the key findings of the report and explain how ESA is helping to address the problem through its Space Safety Programme.
A growing problem
“Economic and societal vulnerabilities to space hazards, in particular space debris, are growing.” – Space Sustainability: The Economics of Space Debris in Perspective from the OECD, 2020.
The institutional and commercial use of space is growing at an increasing rate. The number of satellites in orbit will further increase with the launch of ‘mega-constellations’ for satellite broadband, some comprising thousands of satellites, and with that the risk of collisions and more space debris increases.
Just one collision or explosion in space creates thousands of small, fast-moving small shards of debris able to damage or destroy a functioning satellite. For example, in 2007, the intentional destruction of the FengYun-1C satellite doubled the amount of debris at an altitude of about 800 km, leading to a 30% increase in the total population of debris at that time.
Space debris is expensive, and will become even more so
On the costs of space debris, the report states that: “Space debris protection and mitigation measures are already costly to satellite operators, but the main risks and costs lie in the future, if the generation of debris spins out of control and renders certain orbits unusable for human activities.”
Protecting satellites from space debris is expensive, beginning with design measures, the need for surveillance and tracking, moving operational satellites out of harm’s way and even replacing missions altogether.
For satellites in geostationary orbit, the OECD reports that such costs amount to an estimated 5–10% of the total mission costs, which could be hundreds of millions of dollars. In low Earth orbits, the relative costs per mission could be even higher than 5–10%.
However, the cost of inaction would be far greater. Enough debris in orbit could ultimately lead to the ‘Kessler syndrome’ in which collisions cascade, leading to more and more self-generating collisions, and what the OECD describes as “an ecological tipping point that may render certain orbits unusable.”
Economies and societies are increasingly vulnerable to effects of debris
The socio-economic impacts of the Kessler syndrome would be severe. Important space applications could be lost, such as weather forecasting, climate monitoring, earth sciences and space-based communications. The inability to use certain orbits would have wide-reaching and significant consequences. According to the report, these would include:
- Unique applications and functionalities may be lost e.g. internet, weather and communication services
- Lives lost e.g. increased risk to astronauts in the International Space Station
- Interrupted Earth science and climate research
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