The Space Debris Problem
Space debris. Credit: ESA

The Space Debris Problem

18/11/2021Written by Josh Barker

Following the recent anti-satellite test by Russia, we take a closer look at the problems caused by space debris.

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mascot Telescope Right
The International Space Station above Earth. Credit: NASA

The environment and humanity’s impact on it has become an incredibly important topic to many. One environment that is often forgotten is space! The recent anti-satellite test by Russia once again has the scientific community talking about the space debris problem and our management of the environmental impact we are having.  

Mirroring the clean-up discussions occurring down on Earth, various space agencies are exploring ways to maintain the cleanliness of the space environment through removal of completed mission hardware. As the number of objects in space grows, so does the chance of collision. These collisions not only threaten current missions but also increase the number of objects in space through the creation of debris. This potentially ends up in a runaway cascade of collisions which could ultimately trap us on planet Earth. This terrifying scenario is known as the Kessler Syndrome 

The Origins of the Problem

The Origins of the Problem
This sequence of graphics show the growing quantity of tracked space junk and operating spacecraft orbiting Earth over time. Credits: NASA
The Origins of the Problem
Space debris. Credit: ESA

The problems of space debris began when we started launching things into space in the 1950s. In the early days of exploration, tidying up didn’t seem so important. Space missions were few and far between and space was an incredibly large place. The risk of collisions and the thought of future problems didn’t rear their heads.

However, as our usage of space has grown so has the number of objects currently orbiting the Earth. The most recent count from the US Department of Defence’s Space Surveillance Network is close to 30,000 objects of which over 27,000 are debris alone. This debris consists of old rocket parts, expired satellite missions, fragments created during rocket decoupling and operation and shards created by collisions and previous anti-satellite missile tests.

Tests like Russia’s have occurred before, conducted by India, China and the US and are responsible for around a quarter of the current debris levels. Much of the criticism that is levelled against these tests is that the issues resulting from them have a global effect. Once a cloud of debris is orbiting the earth it poses a threat to anyone who wishes to utilise the space environment. There is a keen desire to keep space available to all and acts threaten everyone’s accessibility not just setting back the perpetrators.  

A Major Threat

It often comes as a surprise that these small pieces of debris, many no bigger than a centimetre, can pose such a threat. However, the colossal speeds we encounter when exploring space result in huge amounts of energy contained in these tiny fragments. The average orbital velocity of an object orbiting at the height of the International Space Station (ISS) is around 23,000 kilometres an hour. At these speeds something the mass of a pound coin would contain a similar amount of energy to a car speeding down the motorway. This results in the potential for catastrophic collisions.

Where possible, spacecraft are designed with protection to minimise the impact of the smallest collisions but incidents with larger objects must be predicted and avoided. This is where tracking services prove invaluable. Constant monitoring from the ground enable satellites and space stations to reposition if a collision seems imminent. The ISS usually makes one or two of these manoeuvres a year to ensure the safety of the crew aboard. These adjustments disrupt operations on board and will need to be made more frequently if we continue to clutter the space environment. Equipment that has returned from space, like the Long Duration Exposure Facility have shown the damage even small impacts can do. 

Solutions

Solutions
Artist's Impression of ClearSpace-1 and its four robotic capture arms. Credit: ESA
Solutions
Artist's impression of a space harpoon. Credit: Airbus

Like the current Climate Crisis, this doesn’t have to be a depressing tale that merely highlights the beginning of the end. Action can be taken to prevent us spiralling into an impenetrable barrier of debris. Agencies and organisations across the world are putting together plans to ensure we take responsibility for the space environment. Keeping it as a safe and open space that we can continue to explore and use to the betterment of society.

Recently the European Space Agency commissioned the ClearSpace-1 mission. This sees a robotic craft equipped with robotic arms launched into space. The craft will capture defunct satellites and then de-orbit them to be burnt up within the Earth’s Atmosphere. Another proposal being considered is the use of lasers to create a ‘laser broom’. This system will use a laser powerful enough to vaporise part of the object’s surface. This will hopefully act as a mini jet engine nudging the debris’ course so that it enters the Earth’s atmosphere to be incinerated.

As research into this area continues, we are also seeing discussions of magnets, nets and even harpoons considered to ensure we can clean up space. Thankfully this issue isn’t just being left to national organisations. A few months ago we saw private industry enter the realm of space clean up. Steve Wozniak, the Apple Co-founder, announced that he would be working with Alex Fielding to create a new business called, Privateer Space, that looks to track debris with even greater accuracy and help with the global objective of tidying up space.  

Space for Everyone

Space for Everyone
Earthrise on Apollo 8. Credit: NASA

Continued development and collaboration like this will enable us to look after the environment of space. By keeping it accessible and open to all, it will allow us to use space for the betterment of society.

By taking responsibility now and progressing in a conscientious way it will keep outer space as a location that can enable exploration and innovation while allowing us to look back upon ourselves and make the world a better place.

About the author: Josh Barker is the Planetarium Coordinator and Education presenter at the National Space Centre.