Space Debris and Contemporary Solutions
All non-functional, human-made objects, including fragments and elements thereof, in Earth orbit or re-entering into the Earth’s atmosphere, are referred to as “space debris” according to the European Space Agency. This ‘space junk’ comes from the thousands of objects that have been launched into space over decades of space activities from Earth, with man-made debris outweighing natural environmental debris. The objects launched into space break or collide in orbit and consequently become a part of the debris’ collection. The need for mitigating space debris stems from the fact that even the smallest of objects can move at the speed of a bullet in their orbit and cause more than significant damage. This concern exists concurrently with the Kessler effect, which describes the occurrence of cascading collisions wherein one collision creates more space debris which further causes more collisions.
Computer-generated images of tracked objects in Earth's orbit. | NASA Orbital Debris Program Office
The current legal regime over space debris follows the suit that an object sent into space requires registration due to Article II of the Convention on Registration of Objects Launched into Outer Space, which was entered into force in 1976. The Outer Space Treaty of 1967 indicates in Article VIII that an object launched into outer space includes its components as well and so any components detaching or malfunctioning count as the same object. International liability of damage or harmful contamination caused by the said object or any of its components is also encapsulated under Articles VI and VII of the Treaty.
One of the methods of mitigating damage from space debris is by de-orbiting these materials and taking them back to Earth’s atmosphere. Controlled re-entry is the most common method for this, but it has also been proven to be heavy, expensive, and unsustainable with respect to fuel usage. The first example of a practical and possible application of this principle can be seen in the European Space Agency’s General Support Technology Programme, which is working on a subsystem that will be programmed to recognize when a component or a satellite has run its course. This was first proposed in 2012 and in 2017, the first iteration of the subsystem was completed and survived several tests. It is supposed to create a membrane around the part of the debris that is to be removed and act as a sail to aid re-entry, however it may take up to 25 years for this process to complete. In addition to the restriction of prolonged time, the system must also be light, scalable enough to use on various spacecraft, and entirely passive, while constantly making correct aerodynamic calculations. This project seems feasible only to the extent where its high financial and human requirements are met. Where it constitutes a step forward in de-orbiting space debris, it also forms a part of an initial stage of development of a technology, which is more often than not an incomplete innovation. So, while the subsystem may be very advanced, the fact that some objects may take up to 25 years to clear out suggests that there are still some factors that need to be achieved at an acceptable level of efficiency.
The second project that draws attention with respect to space debris mitigation is Astroscale, a company based in Japan. In 2019, the company announced that it was testing its ELSA-d spacecraft and launched the same in 2021. ELSA-d is supposed to consist of a service and a client spacecraft, wherein one tests the methods to locate and catch the other. This is conducted using a magnetic plate to grab the client. One of the tests conducted had the client spacecraft spin out of control and the service craft had to match its rotation and attach it to the magnetic plate, much like the docking scene in the film Interstellar. The final test was to use the mechanism to de-orbit a planted “lost” spacecraft and lower the orbit into Earth’s atmosphere where both the objects burn up. This project is a major step forward with respect to managing space debris, it uses technology that is based on very different principles than the European Space Agency’s General Support Technology Programme. Additionally, the reason why this project is more realistic is due to its successful environmental tests as described above, the tests also show that a similar feat to that seen in a science fiction film has now become possible to attempt in real life, becoming one of the most impressive innovations of space engineering.
The third project to be considered in this case is a research project by the European Union to develop, verify, and create cost-effective technologies for future Active Debris Removal missions. The RemoveDebris platform is provided by Surrey Satellite Technology Ltd. This mission includes several experiments to mitigate space debris. First, the Net and CubeSat experiment involves the ejection of the CubeSat at a low velocity which then inflates a balloon to de-orbit and provide a target area. A net is then released when certain proximity is achieved and the net wraps around the target and tightens. The CubeSat then deorbits and clears the debris.
Second, the Vision-based navigation (VBN) experiment releases another CubeSat at a low velocity wherein the VBN camera and Lidar collate information to navigate more accurately to create a three-dimensional image. The next experiment includes a harpoon and deployable target wherein the target approaches the platform along with the harpoon that has a locking mechanism to capture the debris.
The next experiment includes a drag sail as well, similar to the sailing mechanism of the ESA project discussed above, except this concept gets the work done in eight weeks. This mission has gained a significant amount of attention due to the multi-layered approach it takes towards removing space debris, it also deserves the said attention due to the innovative ideas deployed by it to clear space debris and the efficiency displayed by the said ideas. The efficiency is displayed by the same sail program being used more efficiently in this case compared to the ESA project.
All the projects discussed above form a part of the variety of initiatives undertaken by various bodies to tackle the abundant problem of orbital space debris. According to NASA, most “space junk” moves seven times faster than a bullet and this poses a huge risk with respect to all future endeavors into space. To mitigate this, there is a need for responsible practices, stricter laws with respect to launching objects into space without a space debris management plan, and more defined laws with respect to what constitutes space debris and how it must be controlled. Expanding upon this, the need for responsible practices requires, at the very beginning, the acknowledgment of the fact that the bodies which launch objects into space must also bear responsibility for every impact, positive or negative, the said object might have on the environment or with respect to other objects in orbit. This can be translated into a form of Corporate Social Responsibility with respect to evolving responsible practices.
A similar idea is observed with OneWeb, wherein the company’s own Director of Mission Systems acknowledged the company’s responsibility toward the long-term environmental impact of deploying its satellite constellation, the need to create responsible designs and operational practices to manage the environment, and the importance of setting priorities for controlling orbital debris risks. This was done under the company’s Responsible Space Initiative.
International legal provisions must be evolved to create a conducive environment for private or state bodies to engage in similar activities, and to bolster such activities through incentivizing and penalizing those who do not ensure that certain standards are met with respect to mitigating the risks. The idea of creating a similar obligation like corporate social responsibility can be amalgamated with laws to preserve the environment to create legal provisions which reward conscious mitigation and punish, to an extent, irresponsible behavior with respect to space debris. International and domestic provisions both need to formulate laws that have clear definitions with respect to the points discussed above along with what can constitute space debris. This must be a collective effort by all countries which are either directly or indirectly engaging in space ventures along with private bodies. It must also be noted that space debris is a relatively newer threat to the environment, and it remains unclear to some extent, this creates an imminent need to create legislative norms to minimize the risks before they escalate to a degree that cannot be mitigated.