Scaling Sustainable Propellants to Address Rocket Emissions: Lessons From the U.S. Aviation Industry

By: Zhizhou (Josie) Liu The rapid growth of the U.S. commercial space industry has exposed a profound regulatory gap in addressing rocket emissions. By releasing greenhouse gases and particulates like black carbon, alumina, and water vapor, rocket launches not only contribute to climate change but also accelerate stratospheric ozone depletion. The U.S. aviation industry encountered similar environmental challenges decades ago, which eventually prompted legal and policy frameworks to curtail aviation emission through sustainable fuel technologies. Unlike aviation, however, the space industry now operates in a legal vacuum, with no binding international environmental standards or domestic regulations targeting rocket atmospheric pollution. As rocket emissions penetrate into every layer of the atmosphere, their environmental risks are even more intensified and distinct from aviation emissions. This Note argues that sustainable rocket technologies, such as green propellants and green non-chemical propulsion systems, offer an effective pathway to contain rocket emissions. Drawing lessons from the U.S. aviation industry’s gradual regulatory evolution, the Note proposes that a proactive regulatory framework, including industry-specific emission standards, incentive programs, and international collaboration, is critical for the U.S. space industry to avoid replicating aviation’s delayed response and to ensure that the new space era proceeds within environmentally sustainable bounds. Download

To Infinity and Beyond (And Beyond): The Legal and Ethical Imperative for Rocket Reusability

By: Matthew Lumia Although the Space Shuttle’s first flight was in the 1980s, reusable rocket technology did not achieve mainstream viability until SpaceX’s reusable Falcon 9 rocket revolutionized access to space. This note argues that transitioning to reusable rocket technology is not only a practical and economic advancement, but also a legal and ethical imperative. By analyzing reusable rockets through the “due regard” framework of the Outer Space Treaty, this note demonstrates how reusable rockets mitigate space debris, expand access to space, and can reduce environmental harm. Additionally, reusable rockets address critical ethical concerns by lowering barriers to space exploration, allowing the benefits of space exploration to be shared by more nations, and conserving resources which can be redirected to other pressing needs on Earth. As the global launch cadence continues to rise, widespread adoption of reusable rocket technology is essential to ensuring the long-term sustainability of space exploration while fulfilling international legal obligations and inherent ethical responsibilities. Download Full Article (PDF) Cite: 25 Duke L. & Tech. Rev. 262

The Red Dawn of Geoengineering: First Step Toward an Effective Governance for Stratospheric Injections

By: Edward J. Larson A landmark report by the National Academy of Sciences (NAS) issued in 2015 is the latest in a series of scientific studies to assess the feasibility of geoengineering with stratospheric aerosols to offset anthropogenic global warming and to conclude that they offer a possibly viable supplement or back-up alternative to reducing carbon dioxide emissions. The known past effect of major explosive volcanic eruptions temporarily moderating average worldwide temperatures provides evidence in support of this once taboo form of climate intervention. In the most extensive study to date, an elite NAS committee now suggests that such processes for adjusting global temperature, while still uncertain, merit further research and field testing. Every study stresses the need for transparent international governance of stratospheric injections, especially given that the benefits of such interventions are certain to be unevenly distributed and the risks are not fully known. After examining the roadblocks to such governance, this paper explores the statutory and common law frameworks that could provide some stop-gap approaches until the needed regulatory regime emerges. Download Full Article (PDF) Cite: 14 Duke L. & Tech. Rev. 157