In the age of mega-constellations, are these exemptions still justified?

A decade from now, thousands of tons of satellite and rocket debris may be burning up in Earth’s atmosphere every year, giving rise to large quantities of metallic ash, which, according to experts, could affect Earth’s climate and damage its protective ozone layer. Despite the world’s current race to tackle the environmental crisis caused by decades of unbridled use of fossil fuels, no regulations are currently in place to prevent this potential next- generation environmental problem.

In the U.S., this regulatory conundrum rests on a “categorical exclusion” from the National Environmental Policy Act (NEPA) granted to the satellite industry in 1986 by the U.S. Federal Communications Commission (FCC).

The FCC, responsible for satellite licensing in the U.S., currently registers the highest number of satellites worldwide, having approved SpaceX’s Starlink mega-constellations including its second-generation expansion to 42,000 satellites.

Under NEPA, U.S. federal agencies must consider the environmental impacts of their decisions and allow the public to express concern. But in 1986, the FCC concluded that satellite re-entries pose no significant risk to the human environment. This categorical exclusion means that the FCC doesn’t have to carry out a review of environmental impacts of satellite operations prior to issuing satellite licenses, including those to operators who want to operate fleets of thousands, or even tens of thousands of satellites. As each of those satellites is meant to be replaced every five years with newer, more advanced technology, mega-constellations will generate a steady stream of junk incinerating in the atmosphere.

The U.S. Government Accountability Office criticized the FCC in its 2022 report for failing to reconsider the categorical exclusion in light of the growing amount of this incinerated satellite trash. Opposition against the FCC’s slack attitude is growing with organizations including the American Astronomical Society (AAS) and Public Interest Research Groups (PIRG) having issued statements in the past months calling for more oversight of, and more research into, the effects of satellite re-entries on Earth’s atmosphere and life on Earth.

“It's definitely accurate to say that the nature and scale of space activities has changed since 1986 when that FCC NEPA exclusion was put into place,” Ian Christensen, Senior Director for Private Sector Programs at the Secure World Foundation, told Supercluster. “We're looking at a much different type of activity, much different pace,” added Christensen, who cooperates in an international research project funded by the U.K. Space Agency, which aims to assess the potential environmental impacts of satellite re-entries and provide suggestions for future regulations. 

The annual number of re-entries 40 years ago was on the order of a few defunct satellites per year. Currently, more than 300 satellites and about the same number of used rocket stages burn-up in Earth’s atmosphere each year, according to Jonathan McDowell, a Harvard Smithsonian astronomer and world’s leading space debris tracker.

“It’s hundreds of tons of material re-entering each year,” McDowell told Supercluster.

In a decade, nearly 4,000 tons of old space junk could be vaporizing in Earth’s atmosphere per year, according to data presented at the Workshop on Protecting Earth and Outer Space from the Disposal of Spacecraft and Debris held in September at the University of Southampton in the U.K.

In its 2022 report, GAO criticized the FCC for having “not sufficiently documented its decision to apply its categorical exclusion when licensing large constellations,” and urged the Commission to review its approach. The FCC agreed but said it would wait for the Council of Environmental Quality, a body overseeing environmental protection in the U.S., to revise NEPA implementation procedures. This process is currently underway.

Christensen said it was impossible to “presuppose the outcome of that review,” pointing to the decision of the U.S. Court of Appeals that in July rejected a petition filed by the International Dark-Sky Association against the FCC for its decision to grant licenses to SpaceX to launch tens of thousands of satellites without conducting an environmental review. 

Christensen, however, points out that the FCC is not the only body that needs to rethink its attitude to satellite mega-constellations.

“It’s not only a U.S. challenge,” he said, pointing to China’s plans to deploy the G60 and Guowang mega-constellations to compete with SpaceX’s Starlink in the coming years.

G60 and Guowang are expected to comprise 15,000 and 13,000 satellites respectively. Other nations have their plans too. France-headquartered E-Space, set up by One Web founder Greg Wyler, filed a spectrum application for a jaw-dropping 300,000 satellites in 2022. Wyler’s previous venture, the now fully deployed Eutelsat OneWeb, made do with 650 satellites. Jeff Bezos’ Project Kuiper, expected to begin launching by the end of this year, will add another over 3,000 satellites to the growing satellite population. Canada’s Telesat plans a more modest fleet of 200 spacecraft.

Overall, spectrum applications for about a million satellites have been filed with the International Telecommunications Union, which oversees the use of globally available radio frequencies. Experts, however, think the number of satellites eventually deployed will be more in the order of 100,000 — about ten times as much as orbits Earth today.

In its recent statement, the AAS estimates that the periodic renewal of satellite constellations will result in more than 8,000 tons of satellite junk per year burning in the stratosphere and mesosphere, the atmospheric layers at altitudes of 6 to 31 and 31 to 53 miles respectively.

Just like the FCC, other nations overseeing those ambitious space projects have currently no tools to keeps tabs on their environmental impact.

“The environmental impacts of space activities, such as satellite operations, are currently overlooked in European space and environmental legislation,” Yana Yakushina, space policy researcher at Ghent University in the Netherlands told Supercluster. “While the European Union has a robust legal and policy framework for tackling a wide range of environmental issues — from habitat conservation to climate change mitigation — space activities remain an area with significant regulatory gaps.”

Even the European Green Deal, which binds EU member states to achieve climate neutrality by 2050 lacks provisions for the atmospheric effects of the space sector, Yakushina added.

This novel environmental threat, in fact, exists in a strange in-between space that doesn’t concern any existing laws ever conceived by humans. According to Rachael Craufurd Smith, a space and policy law expert at the University of Edinburgh in the U.K., no existing international space treaty considers the problem of air pollution created by re-entering satellites.

The main international document governing space utilization and space exploration is the Outer Space Treaty ratified in 1967. This treaty, however, is only concerned with possible contamination of celestial bodies with matter from Earth and with a possible spread of extra-terrestrial stuff on our planet.

The Liability Convention, signed in 1972, focuses on harm done by satellites and rocket bodies to humans and property on the surface of Earth. If a satellite launched by one nation falls on the territory of another, the launching state is fully liable for the resulting damage. But any wider environmental consequences of space flight and utilization are outside the convention’s scope.

Ironically, the satellite pollution problem is being exacerbated by the space industry’s desire to treat responsibly another outer space environmental emergency — space debris.

A document compiled by the Inter-Agency Space Debris Mitigation Committee, which works under the United Nations Office for Outer Space Affairs, recommends space fairing nations to remove defunct satellites from orbit within 25 years from their missions’ end.

The non-binding guidelines aim to keep the amount of space junk hurtling around the planet within limits to prevent devastating orbital collisions. A handful of unfortunate space smash-ups could fill near-Earth space with so much junk that flying anything in orbit could become risky.

The FCC, as lukewarm as it may seem in its attitude to satellite pollution, is leading the world’s efforts to declutter space, and requests an even faster — 5-year deorbit timeframe — from operators applying for its licenses. The FCC’s deorbit rule helps keep orbits safe.

Although research into effects of satellite pollution on Earth’s atmosphere is in its early stages, experts think that ignoring the problem is not the right way forward. According to Minkwan Kim, an associate professor in astronautics at the University of Southampton and leader of a U.K. Space Agency-funded research project, the metallic dust from satellite incineration could have a range of little understood environmental effects. In addition to ozone depletion, it could alter Earth’s heat absorption, affect its magnetic field, increase the frequency of thunderstorms and disrupt satellite communications links.

The AAS also said that higher concentrations of satellite ash particles in the atmosphere might obscure the views of Earth-based telescopes, exacerbating the plight that the growing number of satellites already presents for the study of the Universe due to the streaks satellites leave in telescope images.

Currently, the overall impact of the space industry on the atmosphere is arguably negligible. Only about 0.1% of the overall ozone depletion caused by human activities is a result of satellite launches and re-entries, said Connor Barker, a researcher in atmospheric chemistry modelling at University College London and lead-author of a mega-constellations emissions inventory published in the journal Scientific Data in early October.

Barker, however, warns that dismissing the problem might backfire in the future.

“We have a lot of uncertainty about how this industry is going to grow,” he said. “That's one of the things that makes it hard to project this work into the future.”

Kim warns that because satellites burn up at very high — between 50 and 37 miles — the ash remains in the atmosphere for decades, maybe hundreds of years.

“It’s not like picking up trash on the beach,” Kim said. “It’s physically impossible to collect these particles from the upper atmosphere. It’s going to stay there for a really, really long time.”

McDowell added: “It’s an uncharted territory.”