Emissions Poised to Rocket: Modeling the Environmental Impacts of Low Earth Orbit Satellite Constellations

Abstract

The proliferation of satellite megaconstellations in low Earth orbit represents a significant advancement in global broadband connectivity. However, we urgently need to understand the potential environmental impacts, particularly greenhouse gas (GHG) emissions associated with these constellations. This study addresses a critical gap in modeling current and future GHG emissions by developing an open‐source life cycle assessment methodology, applied to 12 launch vehicles and 24 megaconstellations. Our analysis reveals that fully deploying the 24 constellations would emit about 9.1 Mt CO ₂ . Propellant combustion during launch events (60.9%) and launcher production (31.6%) contribute most significantly to overall GHG emissions, accounting for 92.5% of modeled life cycle emissions. Reusing launch vehicles lowers production emissions per launch by 81%–97% relative to building a new vehicle for every flight, highlighting the environmental benefits of reusability in space technology. The findings underscore the importance of launch vehicle and satellite design choices to minimize potential environmental impacts. The Open‐source Rocket and Constellation Lifecycle Emissions (ORACLE) repository is freely available and aims to facilitate further research in this field. This study provides a critical baseline for policymakers and industry stakeholders to develop strategies for reducing the carbon footprint of the space industry, especially satellite megaconstellations.