Space debris can be considered the biggest concern at international level related to space activities, especially in Low Earth Orbit (LEO). According to the European Space Agency (ESA), space debris could be generated via collisions or by explosions in orbit caused by left-over energy, fuel and batteries, onboard spacecraft, and rockets. Contributing to the growth of space debris are the spent rocket stages and non-functional satellites. The collisions in outer space can start a chain reaction, known as the Kessler effect, defined by the NASA scientist Donald Kessler in 1978. Thus, space debris poses a growing threat to operational satellites and potentially to the future human spaceflight. From a legal perspective, we currently have the IADC and UNCOPUOS space debris mitigation guidelines which are voluntary in nature. The topic of space debris is also closely linked to the sustainability of outer space”.
The roots of environmental law should be devoted to space debris mitigation. The concept of space debris suggests an identified space object and\or elements derived from it, which is impossible to use for its destination and existence, and which assumes high level and accidental risks of impacting near-Earth space, space vehicles, biological objects, and environment. It is necessary to highlight joint content of the main principles of environmental law and foundations of the legal protection of near-Earth space from debris. On this ground, principles separated on the base principles, compliance with which is a condition for sustainable access to near-Earth space, which is environmental security and long-term sustainability, and derivatives of the “pay for littering”, to avoid any harmful interference with the peaceful exploration and use of outer space, transparency and confidence-buildings, common but differentiated responsibilities, precautionary principles. Each of them is a pillar for further development of legal protection of near-Earth space from debris, which is revealed through legal instruments of environmental law such as licensing, evaluation of environmental impact, rationing, standardization, ecological taxing, and insurance examined. Licensing is a mechanism for the enforcement of other ecological instruments. The evaluation of the impact of space projects for compliance with standards for maximum allowable littering (rationing) is proposed to establish as a base of the tax rate. Quantitative indicators of maximum permissible littering suggest determining by parameters such as weight and quantity. The gradation of these indicators should be defined as units of the tax base, on which the tax rate is established. The implementation mechanism of this measure lays in the obligation of the subject to make a report about the influence of the space project, planned by him. This report would be transmitted to the expert commission for evaluation. It can define the levels of innovations and ecological security (standardization), on which ecological tax rates are adjusted. Results of evaluation of the impact of space projects on the littering of near-Earth space may be used as a source for evaluating risks for insurance contracts. Mechanisms of environmental insurance are suggested expanding by the means of compulsory liability insurance, caused by identified space debris and voluntary insurance of damage caused to near-Earth space. The last one can be the reason for granting tax concessions. Part of these taxes could be transmitted to the global fund for space debris remediation in the case of its establishment.
Space activities play a significant role in improving the quality of life and tackling challenges, like climate change, whilst continuously contributing to socio-economic benefits they produce. The ambitious, innovative concepts of private entities and traditional space actors relying on advancements in technology, enable low-cost development, miniaturization and deployment of numerous objects in one single launch. Whilst technically attractive, this causes an exponential growth of the object population, particularly in the congested LEO. Risks of collisions and in-orbit break-ups lead to dangerous cascade effects (Kessler Syndrome). The amount of space debris is one of the greatest challenges for the long-term sustainability of space activities; it impedes the use of orbits and the Kessler Syndrome is a constant threat. Space debris generate immense associated costs, impacting negatively on socio-economic benefits. The corpus iuris spatialis contains several important obligations calling for sustainable space, e.g., Arts. I, II, III OST, with references to international, and by definition, international environmental law, and Arts. VI, VII, IX OST. The following soft-law frameworks address the issue of space debris: IADC Space Debris Mitigation Guidelines; UN Space Debris Mitigation Guidelines; European Code of Conduct for Space Debris Mitigation; ISO standard 24113:2011 (Space systems: space debris mitigation requirements); ITU recommendation ITU-R S.1003 (Environmental protection of the geostationary-satellite orbit); and LTS Guidelines. While these guidelines are generally complied with, the standards require constant perfection to achieve the goal. National space laws and/or product assurance and safety requirements contain provisions for space debris mitigations as licensing prerequisite. Pre-mission environmental impact assessments are increasingly significant, with sustainable mission concepts becoming competitive advantages from a regulatory perspective. The LTS guidelines contain the first internationally (by consensus) agreed building blocks for an urgently needed international STM regime that takes legal, technical, economic and political considerations into account. This could provide the necessary framework and incentives for responsible, safe and sustainable space operations. The international community must continue to work on multilateral solutions to regulate the increase in space traffic and look towards addressing ADR, e.g. with norms for lawful interception with space debris under consideration of related property rights. Outer space is res communis omnium. Adverse changes to its valuable environment concern the entire community. Sustainability, i.e., preserving the Earth and space environment to meet the needs of those present while preserving it for future generations, must be a fundamental principle underlying all future activities.
Space debris can be assessed from a number of different perspectives: souvenirs of the exploration of outer space by the human race; a typical example of the constant damage caused by the passage of humans to the environment in which they operate and live; an evidence of the historical indifference of governments in order to further their space ambitions; a necessary evil of the first, “heroic” phase of our journey to the Stars. In any case, the silent anarchy of space debris is increasingly taking over the earth’s orbits, a real space Frankenstein, ready to destroy its creator. As Frank Schätzing vividly described in his novel, Limit (2009): “…Space debris, whose unwelcome omnipresence was down to an unparalleled orbital congestion, begun in the 1950s by the Soviets with their Sputnik launches. Since then, the remnants of thousands of missions had circulated at every altitude: burnt-out propulsion stages, decommissioned and forgotten satellites, wreckage from countless explosions and collisions, from complete reactors to tiny fragments of shrapnel, drops of frozen coolant, screws and wires, bits of plastic and metal, scraps of gold foil and vestiges of flaked-off paint. The constant fracturing of the splinters with each fresh collision meant that they were breeding like rodents… The problem was, a wasp hurtling at a luxury limousine with the momentum of an identically sized fragment of space debris would have developed the kinetic energy of a hand-grenade and written off the vehicle in an instant”. It is encouraging, however, that the international community has woken up and has already taken significant steps to curb the tsunami of debris in outer space (UNCOPUOS Space Debris Mitigation Guidelines). However, this is not enough: It is further required to promote a collective space consciousness, at the level of Humankind, which will override national egos and will now allow the collection and removal of the cancers that humans have recklessly sown in space, and which increasingly threaten a healthy and sustainable “use and exploration” of the space domain. The question is: how ready are we for the next step?
The intensification of space activities, the growing number of objects in space and the emergence of new actors, are increasing the risk of collision and the amount of space debris. To this end, various national, European and global initiatives are currently addressing space debris. Among others, the UN COPUOS Guidelines for the Long-term Sustainability of Outer Space Activities and the IADC Space Debris Mitigation Guidelines were developed – which unfortunately experience too little compliance because these guidelines are voluntary and non-binding. In addition to the growing number of commercial activities, political tensions are transferred in space which increases the generation of space debris. For instance, the direct-ascent anti- satellite test conducted by Russia in November last year created approx. 1.500 new pieces of orbital debris. What is required to tackle the challenge of increasing space debris? First, the basis for the surveillance of the space environment and all further measures is sharing of technical SSA data. Even though the number of SSA data sharing agreements is increasing, there is still a big lack of information and data. The exchange of SSA data is still the necessary condition for further efforts and more data sharing agreements are needed. Second, the challenging effort to establish a global STM framework is moving on slowly. STM is supposed to contribute to preventing collisions of satellites. The EU is working on a European STM framework in different projects, such as SPACEWAYS and EUSTM. Once a European common approach is fully developed and adopted, it can be proposed in multilateral discussions through UNCOPUOS. Third, space debris active removal has been gaining increasing relevance. ESA identified active debris removal technologies as a strategic goal and is addressing this issue in its Clean Space initiative, looking at required technology developments to capture debris. Fourth, in-orbit-servicing and new technologies, such as collision avoidance, are pushed forward. Capabilities to repair space systems in space are key to mitigating space debris. Moreover, satellites equipped with collision avoidance systems can conduct avoidance manoeuvres. This summer 2022 saw various efforts towards more sustainability and safety in space. For instance, in June, the Space Sustainability Rating was launched, which aims to increase the transparency of space debris mitigation efforts by providing a score representing the sustainability of a mission. Since there is only limited compliance to international space debris mitigation guidelines (such as UN COPUOS LTS-guidelines), new incentivising concepts to ensure long-term sustainability in space need to be developed.
Space debris covers defunct artificial objects in outer space, particularly in those orbits that are important for human use. Those pieces of debris can include non-functional spacecraft or defunct spacecraft, launched vehicles, mission-related debris or fragmentations form breakups of derelict rocket bodies and spacecraft. It has been measured by the US Space Surveillance Network that nearly 25.000 artificial objects are moving though low earth orbit including 2218 operational satellites. These are those objects that are big enough to be tracked. More than 128 Mil. pieces of debris smaller than 1 cm and about 900.00 pieces of debris between 1 – 10 cm as well as around 34.000 pieces of debris larger than 10 cm are estimated in orbits around the Earth. Below 2000 km altitude, pieces of debris are denser than meteorites. Most are dust from solid rocket motors, surface erosion debris like paint flakes and frozen coolant from RORSAT which are nuclear powered satellites. Most recent events of producing large pieces of debris include the 2007 Chinese anti-satellite weapons testing and a 2009 satellite collision of a Russian and an American satellite. The whole situation with regard to space debris is of major concern because of the so-called Kessler-effect. Because of the very high velocity of debris pieces in outer space even very small debris particles can crash and thus produce more pieces of debris. One speaks of the so-called Cascade or Kessler – effect. As concerns legal mechanisms against space debris one must say that current international space legislation and particularly the Outer Space Treaty, Article IX, are not directly or even indirectly addressing the problem. Therefore since 1998 a so-called Interagency Debris Committee (IADC) met and eventually adopted the so-called Space Debris Mitigation Guidelines which in 2005 were accepted by the United Nations General Assembly. These nonbinding guidelines try to mitigate the creation of space debris in that they e.g. recommend not to continue ASAT testing. Moreover, before the end of the mission, those responsible for the mission should either propel the space object (mostly satellites) into a graveyard orbit or to bring it down to earth so that it will be destroyed whilst re-entering the earth atmosphere. More difficult and thus less advanced is the legal coverage of space debris remediation. Here not even non-binding principles have been agreed upon so far. This is however, necessary all the more techniques like harpooning or catching in a tether to secure pieces of space debris are already known and could be used. However, the problem of costs is the overall problem with regard to space debris remediation. And here it is particularly difficult to establish a causal link between the tiny piece of space debris and its authorship. Therefore, in the future it could be advisable to leave away costs for the remediation of already existing space debris but for the future to make any use of outer space depending on the payment of a fee. This is the old idea that the use of nature must cost which could come to a recovery of the external costs of this activity. And the money to be paid in the fund could be used for the cleaning up of outer space through professional cleaning up enterprises.