Citing environmental concerns, 120 astronomers and researchers implored the Federal Communications Commission (FCC) in an Oct. 24 letter to halt launches of internet satellites like SpaceX’s Starlink.
The letter, which was organized by the Public Interest Research Group, also urged FCC Space Bureau Chief Julie Kearney to investigate the potential negative environmental and health impacts of the vast projected increase in satellites being disposed of in the atmosphere.
Launches are increasing
The number of existing satellites has increased 12 times over in the last five years, with SpaceX alone launching around 60 percent of them. And in 2022, the U.S. Government Accountability Office (GAO) predicted 58,000 satellites would be launched by the end of the decade.
Under existing practices, to avoid the possibility of long-term defunct space junk, satellites in large megaconstellations are placed in a low orbit so that they naturally deorbit after five years. They must then be replaced by subsequent launches.
Such satellites have increased global internet access. But the letter argues that unfettered competition between multiple megaconstellations should not be placed above possible environmental harms.
The American Astronomical Society (AAS) sent a letter to policymakers detailing similar concerns on Sept. 27.
Increasingly, researchers have flagged potential environmental impacts from satellite megaconstellations — not only in emissions from launches but also metals burning up in the atmosphere when satellites reenter. The AAS estimated that a 42,000-satellite constellation vaporized on a five-year cycle would deposit at least 8,000 tons of metals into the atmosphere annually. And a study published in June in Geophysical Research Letters projected that the continuous disposal of megaconstellation satellites in the atmosphere would release nearly 400 tons of aluminum oxide compounds annually into the upper atmosphere, which could significantly deplete the ozone layer.
Satellite megaconstellations have already been under scrutiny for the light pollution, which can negatively impact astronomical observations and animal behavior.
Related: Megaconstellations are changing the night sky forever
Environmental concerns
The problem, says PIRG, lies in how the FCC categorizes satellites under the National Environmental Protection Act (NEPA). This legislation requires an assessment of any major federal action that significantly affects the environment. In issuing licenses for satellites, the FCC has exempted large constellations from review. The letter called on the FCC to end its practice of categorical exclusions for satellites, noting that the GAO found that the FCC “doesn’t have a documented reason” for doing so.
The FCC is planning to review its categorical exclusion policies and expects to develop revisions to its current NEPA rules with the Council on Environmental Quality, which governs these policies, by July 1, 2025.
