To date, according to data and software for monitoring satellites in orbits developed by ESRI, there are more than fourteen thousand satellites in orbit, of which about seventy-eight percent are no longer functioning. Furthermore, as stated by ESA’s Space Debris Office regarding the number of estimated fragments, there are thirty-four thousand objects larger than ten centimeters, nine hundred thousand objects between one centimeter and ten centimeter, and almost one hundred and thirty million objects between one millimeter and one centimeter. The indicated objects can be either fragments or simply no longer operational objects that remain in orbit.
Objects of such a small size, which on Earth are normally harmless, in orbit assume absolute importance in terms of danger for any type of satellite, becoming real projectiles with very high kinetic energy. An orbiting object can reach speeds of several thousands of kilometers per hour. The problem of space debris has been the subject of a famous theory by NASA scientist Donald J. Kessler. He hypothesized that, sooner or later, the density of objects in low Earth orbit (LEO) would cause cascading collisions that would make space activities and the use of satellites in specific orbital ranges impractical for many generations.
If a solution is not found to the inexorable increase in space debris, hundreds of satellites could be damaged and rendered useless.
Hundreds of billions of dollars in the space economy would therefore be at high risk. The protection of satellites from space debris can be qualified itself as a cost, starting from the need to design and build more resilient satellites, as well as to monitor and track dangerous debris. For satellites in geostationary orbit, the OECD reports that costs amount to an estimated five to ten percent of total mission costs, amounting to hundreds of millions of dollars. In low Earth orbit (LEO), the relative costs per mission could be even higher.
Not only strictly economic aspects, but also socio-economic aspects more generally. The Kessler Syndrome would mean that space technologies that make everyday life easier would be unusable, from smartphones to home automation systems, and GPS navigation. Many other applications closely linked to satellite systems would be jeopardized, including weather forecasting, monitoring climate change and natural disasters, and precision agriculture.
The congested orbits being the result of the increasing presence of space debris calls for some geopolitical considerations. First of all, in recent years, many countries have had the opportunity to deploy their first satellite and therefore, to have direct access to space: in 2006, forty-seven countries were investing in space and, probably, in a couple of years, they will reach eighty. This almost exponential growth is due to the reduction of construction, launch and management costs, as well as the development of new technologies and the introduction of “rideshare”. On the other hand, however, with the increase of space actors, there will certainly be an escalation of competitiveness involving the need to develop more independent applications and thus, the need to deploy additional constellations with different functions.
Another factor to be taken into consideration is the trend related to mega-constellations, in particular of small satellites for telecommunications and Earth observation: in fact, an increasing number of satellites in orbit, even if small in size, is leading to a progressive crowding of the orbits, with a consequent increase in the risk of accidents and collisions and the creation of further debris. Finally, the third critical factor relates to the attention of governments and the public to environmental and sustainability issues beyond the atmosphere. For example, crowded orbits make it difficult to observe the firmament because of reflections of sunlight off orbiting satellites. In addition, it is in the interests of both those managing satellite operations commercially and government agencies to keep orbits as manageable and sustainable as possible to ensure the proper and fully operational function of in-orbit infrastructure.
The ultimate goal of managing and controlling in-orbit sustainability cannot be separated from the proper implementation of the space law framework available to us today. Therefore, the most conspicuous part of the regulations concerns preventing the space debris phenomenon (so-called mitigation measures).
First of all, the issue of environment and orbit sustainability is not regulated by any international instrument systematically. However, it is useful to consider articles I, II and IX of the 1967 Outer Space Treaty, containing some general references. More specifically, Article I, expressing the four fundamental freedoms concerning space activities (of access, exploration, use and scientific research), specifies that these freedoms are not absolute since their purpose is to benefit present and future generations. Article I is also closely related to the international law of sustainable development “meeting the needs of the present without compromising the ability of future generations to meet their own needs” as defined by the Brundtland Commission in 1987. Indeed, the principle of sustainable development requires States to use resources rationally so that they are not depleted in the long run, thus linking in turn to the concept of intergenerational equity.
The provision of Article I is complemented by that of Article II of the same treaty, which provides for the prohibition of appropriation of space by claiming sovereignty, by use or occupation or by any other means.
The exponential increase of launches we are witnessing, implying an increase of space debris, is, in fact, a progressive appropriation of terrestrial orbits. In other words, the permanent occupation of a particular orbital area with space debris for a sufficiently long time, permanently excluding any third party from using that area, would be equivalent to an illegal appropriation of that area.
It seems that a real threat to the future sustainability of any operation in space is taking shape, to the detriment of future generations and of the technologically less advanced States in the sector, which are currently unable to “occupy” those orbital areas that they might one day need.
Article IX, finally, contains the fundamental discipline on the adoption of appropriate precautionary measures to preserve the integrity of space, requiring States to adopt certain technological standards. What characteristics should these standards have? In this regard, one might consider the “Draft Articles on the Prevention of Transboundary Damage from Hazardous Activities”, developed by the International Law Commission, where it is stated that “the standard of care against which the conduct of the State of origin should be examined is that which is generally considered appropriate… to the degree of risk of transboundary harm in the particular case”. It also requires legislative, administrative and supervisory measures that reflect relevant international standards to prevent the specific risk.
Although there are no generally recognized international standards, international organizations and States are adopting the Inter-Agency Space Debris Coordination Committee (IADC) standards, an international forum of governmental bodies to coordinate activities regarding space debris issues. The latest version of the 2007 text, in paragraph 5.3.2, provides the so-called “25-year rule” for all satellites that cross LEO or have the potential to interfere with it. These satellites must then be deorbited or otherwise moved to an orbit whose period of stay does not exceed twenty-five years from the end of operations. The main problem with this, as with other standards, is that legally they belong to the soft law category. In other words, their adoption is not mandatory for States. This lack of compulsoriness could cause huge problems in the future, as mentioned above when space debris from large satellite constellations could concretely impede access to Earth orbits. Conversely, the large satellite constellations themselves could be plagued by the presence of space debris, creating a dangerous vicious cycle that could affect all other space activities.
The ideal solution, though hardly feasible, would be to form an international agreement that clarifies disposal duties and imposing other obligations on users, such as an obligation to pay a sum before launch into orbit that includes the cost of disposing of that satellite, or the obligation to pay a bond in the event of non-compliance with active debris removal (ADR) obligations could then cover the cost of such negative outcomes.
The inherent difficulty in forming such an international treaty would lie in the very lengthy procedures required to find a consensus on the provisions. Also, as is well known, some States such as the U.S. are quite reluctant to bind themselves to new international treaties.
This article was written by Ivan Fino, Pietro Santoriello and Gabriele Faggioli (Partners4Innovation).