The annual meeting of the American Society of International Law, held each spring in Washington, D.C., usually features at least one panel sponsored by the Space Law Interest Group. In prior years, some of these panels have focused on the kind of attention-grabbing topics that have inspired generations of Hollywood screenwriters, such as how the nations of the world might respond if scientists determine that an asteroid is on course to strike the Earth and cause catastrophic damage. The subject of this year’s space law panel was a bit more mundane: the problem of space junk and what to do about it. Space junk is defined as any artificial (human-made) object within the Earth’s orbit that no longer serves a useful purpose. The term encompasses everything from defunct satellites and spacecraft, to the remnants of launch vehicles, to tiny fragments left behind after the disintegration or collision of other pieces of space debris. Panel members were asked to consider whether, and to what extent, international legal regimes developed to protect marine ecosystems and remediate pollution in the world’s oceans could be applied to address the issue of space junk.
The panel consisted of Timothy G. Nelson, a partner at Skadden, Arps, Slate, Meagher & Flom, LLP, specializing in international litigation and arbitration; Ruth Pritchard-Kelly, a senior advisor on regulatory and space policy at OneWeb, a satellite telecommunications network based in London; and Andrés Villegas, co-chair of the International Litigation and Arbitration Division at Sygna Partners (Paris) and a former senior legal advisor at the Ministry of Foreign Affairs of the Republic of Colombia. Viva Dadwal, an associate attorney at King & Spalding specializing in international arbitration, served as the moderator.
Dadwal provided a contextual framework for the discussion by sharing some rather alarming statistics comparing the enormous amount of plastic waste that has accumulated in the world’s oceans with the rapid proliferation of space junk orbiting the Earth. Each year more than 300 million tons of plastics are produced worldwide, and at least 14 million tons of plastic waste end up in the world’s oceans. Plastics now account for roughly 80 percent of all marine debris, from surface waters to deep-sea sediments. Unlike organic matter, plastics do not decompose and so will remain present in marine ecosystems indefinitely. Nevertheless, many commonly used plastics are prone to breaking down over time into smaller and smaller particles, known as micro-plastics. Of the estimated 50 to 70 trillion pieces of plastic in the oceans, the majority of these are micro-plastics. By 2050, according to some estimates, there may be more plastics in the oceans (by weight) than fish.
Although space junk is a more recent phenomenon than plastic waste in the oceans, the accumulation of debris orbiting the Earth is no less alarming. According to models produced by the European Space Agency’s Office of Space Debris, there are currently an estimated 36,500 objects greater than ten centimeters in diameter within the Earth’s orbit. The volume of smaller space debris is even greater: an estimated 1 million objects between one and ten centimeters in diameter and an estimated 130 million objects between one millimeter and one centimeter in diameter. The danger is that repeated collisions of space debris over time could result in a cascade effect, in which larger and larger clouds of accumulated debris will make it increasingly difficult for satellites to operate in Earth’s orbit. This phenomenon, also known as the “Kessler syndrome,” could, in a worst-case scenario, make it impossible to safely launch new satellites into orbit around the Earth or to safely launch exploratory vehicles into outer space.
To kick off the discussion, Dadwal quoted from a letter to editor published in the March 10th issue of Science magazine, in which several prominent scientists asserted that, like the high seas before it, the Earth’s orbit is being treated as a global commons, and that the exploitation of what appears to be a free resource obscures the true cost of environmental damage. The authors of the letter went on to call for international cooperation to address the urgent need to reduce the volume of space debris before the Earth’s orbit suffers the same fate as the world’s oceans. Dadwal asked Nelson if he agreed with the underlying premise of the scientists who wrote the letter to the editor, namely that the international legal regimes developed to protect the world’s oceans can be applied to remediate environmental damage in space.
Nelson agreed with the underlying premise in principle. Nevertheless, he emphasized that there are critical differences between the physical properties of space and those of the world’s oceans. These differences are easily obscured by pop cultural references that equate space travel with maritime navigation. Long before space exploration became a reality, science fiction writers deployed maritime terminology to describe what are now universally referred to as spaceships. So ingrained in our popular culture are these maritime metaphors (These are the voyages of the starship Enterprise.) that it is tempting for the casual observer to assume that space law can simply adopt the legal paradigms designed to safeguard the oceans. In practice, Nelson noted, these paradigms must be modified to reflect the profound physical differences between the maritime environment and the space environment.
Foremost among these physical differences is the fact that space debris orbiting the Earth at very high speeds possesses enormous amounts of kinetic energy. As a result, even debris as small as one centimeter in diameter has the potential to cause catastrophic damage if it collides with a satellite or a space vehicle. Any new legal regimes developed to address the problem of space junk must take this intrinsic danger into account. In contrast, human-made maritime debris, known as flotsam and jetsam, poses little risk to travel and shipping on the high seas. Larger ocean-going vessels can sail through it, and smaller vessels can navigate around it.