As rockets launch more and more, their environmental effects should be taken into account, according to a new study published in the journal Physics of Fluid.

Rockets on the whole don’t produce as much pollution compared to global aviation, but this will change as more and more of them are launched. The biggest offenders in this are SpaceX, with their seemingly weekly Starlink launches, but also suborbital tourism providers Blue Origin and Virgin Galactic.

The team from the University of Nicosia studied the effects of a simulated rocket plume up to an altitude of 67 kilometers. They found that the combustion product nitrogen oxide was concentrated up to an altitude of 10 kilometers, where the atmosphere can spread it higher and further. The 10-kilometer limit is because of the pressure when it leaves the end of the rocket engine bell.  According to the team’s fluid dynamics simulation’s worst-case scenario, the rocket emits enough nitrogen oxide to make two cubic kilometers of atmosphere hazardous to humans

Carbon dioxide is another combustion product, and the team found that a rocket would produce the equivalent of 26 cubic kilometers of CO2 for every one kilometer of altitude traveled.

The team does not know how long it takes for these different combustion products to disperse into the atmosphere. Above a certain level of rocket launches, the natural level of pollutants will go up. This will make climate change worse. Paper co-author Dimitris Drikakis said: We hope that commercial flight companies, such as SpaceX, Virgin Galactic, and the New Shepard, and their associated engine manufacturers, will consider these effects in future designs.

More Information

AIP press release

“Atmospheric pollution from rockets,” Ioannis W. Kokkinakis and  Dimitris Drikakis, 2022 May 17, Physics of Fluids