Recruiting AI for Orbital Chaos

Around fifteen thousand million years ago, the Universe suddenly came into existence in a tremendous explosion – the Big Bang, a colossal explosion that scattered energy and mass. The gases rushing outwards from this explosion eventually turned into galaxies, stars, and planets, including our solar system. From that cosmic chaos emerged Earth, and with it, the human species reached back to the vast cosmos with satellites and space missions, from simply gazing into the dark sky to setting footprints on the moon. Decades later, not only do we have left footprints or scientific instruments on Mars, but we’ve left a growing trail of space debris orbiting our planet like a minefield. With the rapid expansion of space technologies, the need to tackle the issue of space junk intensifies. Fortunately, Artificial Intelligence (AI) offers ground-breaking solutions to tackle this issue, safeguarding our progress in space exploration and long-term sustainability.

Every 8 minutes, a high probability collision alert is triggered for satellites operating in Earth’s orbit. Space junk, also referred to as orbital debris, can be defined as any human-made object in space that is not functioning or serving no longer purpose left by humans. According to NASA, there are around 6,000 tons of space junk in low Earth orbit (LEO), and most of this garbage is moving very fast, reaching 18,000 miles per hour, which is almost seven times faster than a bullet. There are many reasons why LEO has developed a debris graveyard; for instance, the destruction of the Chinese Fengyun-1C spacecraft in 2007 and the accidental collision of an American and a Russian spacecraft in 2009 alone have increased the debris population by 70%. Collisions between objects can create even more debris in a compounding effect known as the Kessler Syndrome – a situation in which a buildup of space debris in LEO can lead to a chain reaction of collisions, creating more debris over time. These collisions can damage satellites, space stations, and rockets for future space missions. Not only does it cause financial losses, but it endangers human lives by the chance of hitting the Earth’s surface, potential for environmental damage, threatens human spaceflight missions, and disrupts essential services that we rely on. 

Currently, various detection and tracking methods, such as Ground-based radar and telescopes, are used to detect objects that are more than 10 cm in size with manual data processing and cataloging. Today’s methods rely primarily on human-reviewed collision predictions using mathematical models and reactive planning. Moreover, this traditional method is experimenting with missions using robotic arms, nets, and harpoons, which are operated manually. For example, the Remove DEBRIS (2018-2019) launched by the International Space Station (ISS), a mission by the University of Surrey (U.K.) with partners, including Airbus, tested low-cost methods of debris capture. In that mission, all three traditional techniques- net capture, harpoon test, and drag sail were used to accomplish one of the first missions to mitigate space debris solutions. Although the mission proved that traditional, pre-programmed control systems could perform key-debris removal maneuvers, it highlighted the limitations of these systems in handling unpredictable or dynamically changing debris scenarios, the high cost of carrying out such missions, limited real-world applications, and complex energy and mass constraints. This is where the pivotal role of Artificial Intelligence comes in.

While traditional radar systems provide vast amounts of valuable data, the sheer volume of objects in orbit makes monitoring difficult in real time. Also, much debris is still untracked or has incomplete information, making it difficult to trace their trajectories. AI, however, can identify and categorize debris more efficiently and accurately than human beings. Machine Learning (ML) algorithms, for example, can analyze tracking data to predict potential collisions and trajectories of debris pieces. By doing so, AI can provide early alarms or warnings to help prevent catastrophic encounters between debris and operational systems in space. Currently, satellite operators receive numerous alerts about potential collisions, but many of them are false alarms. AI can evaluate multiple variables such as object size, velocity, and orbital decay, enabling it to predict collisions with a much higher level of accuracy. Furthermore, AI-powered autonomous systems are already in development to help satellites make real-time decisions. These systems can automatically reposition satellites when a collision is predicted, saving resources and minimizing human intervention. One of the most exciting potentials of AI is autonomous debris removal. Robots powered by AI can autonomously locate, capture, and deorbit dangerous space debris. For instance, ESA’s ClearSpace 1 mission, set to launch in 2028, will attempt to use 4 AI-powered robotic arms to achieve a target of 95 kg of material. 

One futuristic but increasingly viable solution is to use ground-based or satellite-mounted lasers that can de-orbit the debris’ trajectories, heating up on one side and altering their path. This approach is not meant to destroy the debris directly; instead, it uses the knowledge of physics to heat one side, causing the material to vaporize slightly, and this vaporization creates a small amount of thrust in the opposite direction to slow down and enter the Earth’s atmosphere to burn up. So far, most of the real-world applications to use highly powered AI lasers are still in research or mostly theoretical. For instance, a ground-based laser tracking system created by Australian EOS space systems and Lockheed Martin can mitigate space debris collisions by using AI to track, classify, and guide impulses to subtly change their orbits. This is a non-destructive method that uses photon pressure, which perhaps avoids the formation of secondary space debris. These systems eventually pose no threat to human beings on Earth and in the atmosphere where air activities are held. Firstly, the ground-based lasers hit the debris vertically upwards, meaning this can only happen when the atmosphere is clear, and no object is between the targets. Secondly, after altering the path of the debris, it is forced to enter the Earth’s atmosphere and burn, causing no harm or damage to anything. Also, Earth is covered with 70% water, which could be the least possible probability of getting hit on land where humans reside. A NASA report found that space-based lasers are advantageous compared to ground-based ones because they don’t need to pass through the Earth’s atmosphere, which could deform the beams. Being in space can more easily pulse the target object into favored orbits. While Ground-based lasers are affected by dust, clouds, and air turbulence, the energy is lost, passing through distinct levels of the atmosphere. Being in space can more easily pulse the target object into favored orbits and can be operated with high precision with real-time tracking onboard. 

Can we fully trust machines to make split-second decisions in orbit? Who bears responsibility if an AI misfires or targets the wrong object? These questions highlight the complex challenges and ethical considerations AI introduces to space missions. Technically, AI systems depend on accurate and continuous data streams; gaps or errors in sensor inputs could lead to false detections or miscalculations, potentially causing unintended collisions. Additionally, deploying autonomous AI systems introduces the risk of malfunction, misidentification of debris, or unintended geopolitical tensions. For example, the dual-use nature of AI and laser technologies can be repurposed for military actions, thus enhancing the militarization of space. As we move forward, addressing these risks through transparent international regulations, ethical frameworks, and human oversight would be essential to ensure safety and sustainability.

In conclusion, AI stands out to be the leader of a new era in space debris management, offering us advanced capabilities to solve the problem of space debris. Yet, as we embrace AI to secure the future of space operations, it is imperative to carefully consider and address the challenges and ethical concerns. With responsible development, international collaboration, and clear regulations, AI has more potential not just to solve the issue of space debris, but can pave the way for much safer, sustainable space exploration.