A green revolution is beginning in the space business.

The explosion of a rocket is nothing short of amazing. Most of us have vivid memories of rocket launches, complete with the noise of their engines, jets of fire, and smoke trails, whether we were born during the Apollo, space shuttle, or private space eras, or at any other time. Almost everyone on Earth who has access to television or the internet has that image ingrained in their minds.

However, until recently, few people thought about the possibility that those spectacular launches might have left a significant amount of pollution in their wake. It turns out that the worldwide aviation business produces more carbon emissions than the space travel sector, which conducts several dozen launches annually. The number of rocket launches is steadily rising each year as a result of the commercial space industry’s quick development. As a result, the problem’s scope will only expand.

In a paper that was published in the Physics of Fluids journal in May 2022, two researchers from the University of Nicosia in Cyprus, Ioannis Kokkinakis and Dimitris Drikakis, attempted to estimate the potential impact. By combining data from rocket launches with computer simulations, they aimed to quantify the possible threats to human health and the environment.

They came to the conclusion that “pollution from rockets should not be underestimated as frequent future rocket launches could have a significant cumulative effect on climate,” and that it may also become “hazardous to human health.”

Scientists used data from simulations based on the common rocket fuel RP-1. And therein resides one of the most significant issues that the space launch sector needs to address. RP-1, also known as Rocket Propellant-1 or Refined Petroleum-1, is a highly refined version of kerosene that has long served as the industry standard for rocket fuel. RP-1, however, has never been a clean-burning fuel. Black carbon, often known as soot, and tons of CO2 are released into the atmosphere during a launch using RP-1 or a comparable kerosene-based fuel.

There is some good news, though. Although it is still early, it is reasonable to state that a green revolution is beginning in the space launch sector. The global space sector is beginning to show encouraging indicators, and it seems to be gaining momentum.

Reevaluating the fuels being used is where it all begins. Three new rocket launch firms, two in Europe and one in the US, have chosen to base their rockets on propane, a rather unusual but well-known fuel. Strange as it may seem, what most people consider to be camping gas may actually represent the industry’s only hope for survival.

The characteristics of propane make it a very sustainable fuel. First off, it burns very cleanly, preventing the release of black carbon into the sky. In contrast to RP-1, it has a small carbon footprint. According to a University of Exeter study, a “microlauncher” rocket powered by bio-propane, a renewable form of propane, might save CO2 emissions by up to 96% compared to previous rockets of a similar size.

Sutherland Spaceport, a spaceport now under construction in Scotland, is also making a commitment to environmental sustainability. In both building and operation, the creators of that spaceport want to make it the first carbon-neutral spaceport in the world. How the developers want to use the peat removed during construction to repair the peat “scars” in the area’s landscape that were caused by years of harvesting peat for fuel is one practical example of what that implies.

The European Space Agency (ESA) is yet another encouraging indicator for the space sector. Recently, they paid for a study on “Ultra-Green Launch & Space Transportation Systems.” Although this is a long-term endeavor—looking for solutions to be used between 2030 and 2050—the fact that a significant space agency is researching the problem is encouraging for the global space sector.

The European Space Agency has also contributed to the momentum by taking the lead in addressing the problem of space debris, sometimes known as space junk. Anyone who has watched the film Wall-E may see what that could appear to be from space and have a small sense of collective guilt for how humanity has come to this point. Millions of space debris bits are believed to be in Earth’s orbit at this time. The fact that ESA is actively investing in initiatives that aim to actively remove junk, making our planet’s orbit cleaner and more accessible, is one of the comforting elements of their leadership in this field.

In the past five to ten years, it would have been difficult to locate anyone, anywhere, who could relate the phrases “sustainability” and “space.” That is altering, and for the better. However, now is not the time to relax and assume everything will be alright. Sustainability must become an essential component of the space industry’s mentality if it is to thrive in the twenty-first century.

There is little doubt that what may start as polite praise from the periphery for sustainable initiatives will eventually result in financial penalties and regulation. Even while most people find rocket launches exciting and inspiring, the space industry is unlikely to continue enjoying a free pass for very long.

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