The Gravity of Air Pollution from Space Launches

A common depiction of space missions tend to include images of launches: massive, towering rockets that seem almost billowed up by soft smoke. However, have you ever wondered constitutes this white smoke and whether it has adverse impacts on the environment? For this post, I hope to highlight the need for us to be more aware of the gravity of air pollution as things get launched into space.

According to the first published review of the subject, there is surprisingly a lack of studies on launch-based emissions. In “The environmental impact of emissions from space launches: A comprehensive review”, Dallas et al. (2020) found that emissions from space launches are becoming increasingly concerning especially for stratospheric ozone depletion.

In addition, the dearth of research on this sub-topic means that we do not yet fully understand the full impacts of space exploration especially considering the fact that more and more missions are being launched. As it becomes cheaper and more nations begin space programmes for prestige, science, or tourism, it is pertinent that we comprehensively understand what happens back on earth as we hurl metal and people off the planet. In fact, researchers and organisations since 1974 have noticed localised ozone-thinning from rocket emission plumes which all contain NO_X, OH, and H₂O (Ross and Vedda, 2018) – different types of propellants may contain other ozone depleting substances like Cl_X.Al₂O₃ which can further deplete ozone. On the ground, gases like NO_X and N₂O can also be a health concern for all types of launches.

This, of course, are only things that scientists have noticed so far. There may be cause for concern for other emissions based on other propellants. In my next few posts, I hope to dive into greater detail the types of air pollutants emitted during launch off. The decisions made on propellants are typically motivated by costs or practicality, and little goes into considering the harm they have on the environment. Hope you are excited to find out more!

 

References

Dallas, J. A., Raval, S., Gaitan, J. A., Saydam, S., & Dempster, A. G. (2020). The environmental impact of emissions from space launches: A comprehensive review. Journal of Cleaner Production, 255, 120209.

Ross, M., & VeddA, J. A. (2018). The policy and science of rocket emissions. Center for Space Policy and Strategy, The Aerospace Corporation.