The “murky” issue of the atmospheric impact of rocket launches: there is still.

Just as each action has a reaction according to Newton’s third law, it seems that each of the actions that humans have with their inventions has at least one not so desired consequence that in the end ends up leaving a mark on our planet. Space exploration does not escape this, but this time we are not referring to space debris, but to impact of so many rocket launches on the atmosphere.

For a few years we have been living a popularization of the same, seeing that launching satellites and others is no longer just a matter of national or continental space agencies and that there are important private initiatives. Thus, without getting into the numbers yet, it is possible to think that since those first launches by the United States and Russia the number has increased a lot, and in each one there is a combustion and an expulsion of gases and particles.

The “murky” issue of the atmospheric impact of rocket launches: there is still

The fuels used by space rockets

The space rocket engine is not much like that of a car, but there is combustion (and what combustion). It is possible that we have seen some space launch, in fact here we have shared some that have been striking and interesting, in fact we recently reviewed its evolution in the last 70 years and what remained in common is the tremendous column of smoke that is created .

The fuel used is variable, and can be in solid, liquid or gaseous form. In Scientific American Bryan K. Smith, head of the Exploration Vehicle Office at NASA’s John H. Glenn Research Center, cited some of the components used, such as ammonium perchlorate with aluminum, liquid hydrogen, liquid oxygen, or RP- 1 (similar to kerosene), explaining that it depends on the type of rocket and the phase in question.

The “murky” issue of the atmospheric impact of rocket launches: there is still

Low noise and many particles

Regardless, the combustion required for launch produces a series of emissions that contain gases such as carbon dioxide, one of the agents responsible for global warming. Although apparently what is worrying are the small particles that are expelled that could be more harmful to the atmosphere, according to the chief engineer of the Aerospace Corporation Martin Ross, who studies what effects the launches are having on it.

In The Verge they collect the words of the engineer (in the mouth of his association), who clarifies that although the launch industry may be contributing little To increase the amount of carbon dioxide and water vapor compared to others, it would be necessary to pay more attention to their impact. Message that he already tried to convey with a work published in April together with Jim Vedda (another engineer), which raised the need to have knowledge of the emissions of the launches and their impact in the future of a greater number of them, and of having to legislate for its control.

The “murky” issue of the atmospheric impact of rocket launches: there is still

What is being considered is that the magnitude of the deposition of certain particles in the atmosphere is not known and that it should be studied more

In relation to which are the components that are emitted, Ross explains that in addition to the gases that we have mentioned, it is expelled soot and aluminum dioxide (alumina). Particles that remain in the stratosphere and that according to some studies contribute to the dilution of the ozone layer, although the magnitude of this deposition is not yet known and therefore should be studied further, he says.

The “murky” issue of the atmospheric impact of rocket launches: there is still

As to the states in which the fuels are found that we have commented before (solid, liquid and gas), the engineer says that those that produce the most alumina are solids, but that most rockets no longer use these. Liquids are the ones that produce the most soot (used for example by SpaceX’s Falcon 9), which is composed of the so-called dark carbon, whose effects on the environment have also been studied as gathered in this article from the University of Columbia.

Effects such as the absorption of solar energy, which can be a million times more powerful than that of carbon dioxide (they placed dark carbon second on the podium of gases responsible for climate change after CO2 in the Columbia article), although its contribution to climate change is still under study due to interaction with other components (such as sulfates and nitrates).

According to Ross, what happens with soot is that it creates a thin layer that intercepts and absorbs sunlight, acting as an umbrella and being at the same time a cooling and heating factor of the atmosphere. This favors the warming of the atmosphere, so that there are more chemical reactions and more risk of the ozone layer being destroyed by the resulting components.

The “murky” issue of the atmospheric impact of rocket launches: there is still

An impact that may still be small, but that will grow

It is not the first time that it is raised the possible impact of space launches on the atmosphere. It is something that is controlled in each mission, including how it could affect in the event of an incident both in the atmosphere and in other scenarios (we can see it in the New Horizons program or in the Mars 2020 mission).

Before we made reference to those of SpaceX, which have the advantage of being reusable rockets (they mean less atmospheric / space trash and cost savings), but how they affect our atmosphere and space, Nottingham Trent University professor Ian Whittaker spoke in The Conversation.

In addition to RP-1, the Falcon Heavy uses liquid oxygen, which expels a good dose of CO2 in its combustion according to Whittaker. For their part, the Falcon 9 load 440 tons of RP-1, with approximately 43% carbon, an amount per se that is negligible if we take into account the emissions of the entire planet, but which is an amount to take into account if we consider SpaceX’s plan to launch a rocket every two weeks, which in the end would be roughly a few 4,900 tons of carbon per year.

The “murky” issue of the atmospheric impact of rocket launches: there is still

Engineers consider that more should be invested in research so that we know the impact well and act on prevention

To this would be added the residues of alumina and soot, which according to Ross represent an injection of 11,000 tons to the atmosphere per year. For now, Ross and Vedda emphasize in their work, rocket emissions into the atmosphere account for a tiny part of the total, but they urge that more be invested in research so that the impact is well known and act in prevention, so that no as with space junk.

In prevention of this industry growing, which is what it seems, and with it the annual launches. We have already seen that in addition to NASA, ESA and SpaceX there are the space agencies of India, China, Russia and Japan, all with active projects and on their agendas for the next few years.

Images | NASA Commons
In Engadget | Space Junk: A 60-Year-Old Problem, Theoretical Ideas, and Cures Worse Than Disease

The “murky” issue of the atmospheric impact of rocket launches: there is still