Satellite megaconstellations (SMCs) are driving huge growth in the space sector, but lack environmental regulation. Here we construct inventories of emissions from rocket launches and spacecraft re-entry, covering the pre-SMC era (2019) and post-SMC era (2020-2022). We implement these in the GEOS-Chem model coupled to a radiative transfer model to determine the impact of current and future emissions on climate and the composition of the upper atmosphere.

People: Eloise Marais (UCL; PI), Connor Barker (UCL; postdoc), Jonathan McDowell (Harvard-Smithsonian Center for Astrophysics; collaborator), Seb Eastham (Imperial; collaborator), Chloe Balhatchet (Cambridge; collaborator).

Funding: European Research Council (ERC) Starting Grant (StG) UpTrop (851854).

Data and Tools Used: GEOS-Chem, RRTMG.

Related Publications:

• C. R. Barker, E. A. Marais, E. Y. P. Tan, S. D. Eastham, G. S. Diskin, J. P. DiGangi, Y. Choi, A. Rollins, E. Waxman, T. P. Bui, C. Gatebe, J. Dean-Day, R. Poudyal, Radiative forcing and ozone depletion of a decade of satellite megaconstellation missions, Earth's Future, 14, e2025EF007229 (2026), doi:10.1029/2025EF007229. [Article]. [Media coverage].
• C. R. Barker, E. A. Marais, J. C. McDowell, Global 3D rocket launch and re-entry air pollutant and CO2 emissions at the onset of the megaconstellation era, Nature Scientific Data, 11, 1079 (2024), doi:10.1038/s41597-024-03910-z. [Article]. [Media coverage].
• R. G. Ryan, E. A. Marais, C. J. Balhatchet, S. D. Eastham, Impact of rocket launch and space debris air pollutant emissions on stratospheric ozone and global climate, Earth's Future, 10, e2021EF002612 (2022), doi:10.1029/2021EF002612. [Article]. [Media coverage]. Awarded Wiley certificate for most downloaded article in 2022.
• E. A. Marais, Axiom launch: why commercial space travel could be another giant leap for air pollution, The Conversation, 8 April 2022.
• E. A. Marais, Space tourism: rockets emit 100 times more CO₂ per passenger than flights – imagine a whole industry, The Conversation, 19 July 2021.

Related Data:

• Online Launch and Re-entry Emissions Tracker.
• Atmospheric composition and radiative forcing changes from a decade of growth in megaconstellation emissions obtained using GEOS-Chem. C. R. Barker, E. A. Marais (2025). doi:10.5522/04/30003763. [Data].
• Global 3D rocket launch and re-entry air pollutant and carbon dioxide emissions for 2020-2022. C. R. Barker, E. A. Marais (2024). doi:10.5522/04/26325382. [Data].
• Rocket atmospheric impact - Emissions Inventory and Results. R. Ryan et al. (2022). doi:10.5522/04/17032349. [Data].

Media Coverage:

Detailed media coverage on our Media Coverage page.

• Mashable, Space tourism sounds fun. But it could be terrible for the planet.
• The Guardian, How the billionaire space race could be one giant leap for pollution
• CTV News, Space travel is open for business, but what about the environmental impact?
• UCL Geography News, First database of pollutant and CO2 emissions from satellite megaconstellations
• Space.com, How much do SpaceX's reentering Starlink satellites pollute Earth's atmosphere?
• The Guardian, Inventory counts air pollution cost of space launches and re-entries
• Nature.com, Swarms of satellites are harming astronomy. Here's how researchers are fighting back
• Salon.com, Erasing the stars: Satellite megaconstellations are a mega problem for Earth and sky
• Bloomberg, Thousands of Falling Satellites Put the Atmosphere at Risk [Requires subscription]
• NRC, Torrential rain from discarded satellites leaves traces in Earth's atmosphere [Dutch. Requires subscription]