Article 51: Can space travel be sustainable?

Ani Talwar explores the motivations behind space travel, if it can be sustainable for Earth, and if it can be sustainably carried out in space.

Image Credits: Tarcísio_/ Pixabay.

It was a windy day in Texas, with highs of 29 degrees celsius and a forecast for rain, but this didn’t stop the launch of Space X’s latest experiment. Having only ever previously flown in tests at low altitude, the flight of the 20th April 2023 was supposed to achieve a circle of the Earth, before landing with a splash in the ocean. Instead what it got was a fiery end, exploding before it even left the planet. As the news circles over this latest space exploration attempt, what went wrong, and what it means for the next venture, I’m going to take a look into what makes us want to go to space, and what it means for ‘Sustainability’.

Why space travel in the first place?

Space travel has been the subject of movies, songs, and lifetime research, but why are we so fixated on what’s beyond our atmosphere? To work out what makes astronauts and astrophysicists tick, NASA’s motivation is probably the best place to start. Space travel is viewed by NASA as one of the ways to answer key universal questions and map out our history.

Exploring beyond the moon’s orbit, known as Translunar Space, is a way to learn more about some of the greatest threats to our planet, such as radiation. However, exploration isn’t only to help us learn more about how to protect Earth, but also to help us learn about other planets, namely: can life exist on them?

Clearly there’s a reason to venture beyond the comfortable confines of Earth, but what does it mean for sustainability?

According to the European Space Agency, Space travel by default has to be sustainable, because there are so few materials not on Earth that we must make the most efficient and effective use of every scrap we have. To this end, the best bases on extra-terrestrial bodies are those that are self-sustaining, and do not need regular refuelling with materials shipped out from Earth.

In fact, the European Space Agency has spent the last quarter of a century fine-tuning an ecosystem that can be taken into space that should produce the required air, water and waste cycling needed to live off Earth. At the moment, a test version set up in Barcelona of a closed ecosystem is housing a few rats, which are reportedly still alive and not in discomfort.

Image Credits: GDJ Pixabay.

So yes, space travel can be sustainable in space, but what about on Earth?

Clearly some thought has been put into how not to pollute whatever extra-terrestrial body we end up on, but space travel begins on Earth, which has to be mined for materials to make these rockets, so what does it mean for sustainability here?

In space travel, lift off is said to be the most harmful stage, requiring fuel whilst producing large amounts of gaseous pollution. Whilst the SpaceX Falcon 9 rocket released 336 tonnes of CO2, the greenhouse gases aren’t the only ones to watch for. Engines can release soot and chlorine, as well as gases that destroy ozone.

Image Credits: Wikilmages Pixabay.

However, there has been some headway into making sure entering a new planet doesn’t destroy the one we are already on. Some rocket launches are now propelled using hydrogen fuel which produces water vapour. One SpaceX rival, Blue Origin, has tried liquid hydrogen/oxygen on their New Shephard Propulsion Module, however others have noted that obtaining the hydrogen itself for a hydrogen-based fuel comes with its own caveats, usually emitting carbon in the process.

One study also notes that an environmental saving could be made by the reuse of space parts. I’m sure we’ve all seen footage of a rocket entering the atmosphere and the exoskeleton that propelled it into space just falling away, leaving the astronaut in the middle section to continue onwards. What happens to all this debris that is left behind?

It turns out that if we safely collected and reused those parts, we could make a huge saving! The parts from the Falcon 9 rocket, mentioned earlier, could potentially be reused 100 times. This knowledge could not be more relevant, with the Rhessi space satellite scheduled to fall back to Earth earlier this week (Wednesday 19th April 2023 precisely for everyone reading later on), resulting in 300kg of material that will simply burn away as it falls through the atmosphere.

Imagine the things that could be made if that material had been equipped to return safely to Earth allowing for reuse…

So if we can’t guarantee it’s sustainable, should we continue?

There are clearly a lot of caveats when it comes to space travel and what it means for sustainability, both on our planet and off it. If there is so much disconnect between what we do, and how environmentally friendly it is, why do we keep aiming for the stars? Could it be that space travel is not only an educational pursuit, but a necessity?

Consider: Space travel helps us monitor how sustainable we are being on Earth via satellites.

Image Credits: PIRO4D Pixabay.

One benefit of space travel comes through the introduction of satellites which can be used to monitor land use changes on Earth, including illegal fishing and farming, trends in land degradation, and forest loss. Morgan Stanley reports that this can be combined with weather, and temperature data to inform future farming practices based on these trends, maximising efficiency and yields.

Satellites are also instrumental (see what I did there) in monitoring emissions and landfill positions which can help mitigate build-up, as well as sunlight and cloud patterns to assess suitable locations for renewable energy plants.

Consider: Researching how to survive in space can make us appreciate what we have on Earth.

Space travel is challenging, as you’ve probably garnered from news, film, and the earlier portion of this article. However, this challenge may help us to save our own planet first.

By developing long term solutions for human survival in order to facilitate explorations into deep space, technology is being developed which could benefit sectors here on Earth. Several such technologies have already made this jump, such as crop growth projects using different types of light, or different liquids other than water. The Scientific American reports this amongst other examples, such as a slow release fertiliser which can reduce runoff concerns if deployed on Earth, or a spray for space equipment which can help clean up the harmful chemicals required in manufacturing once they’re in the environment. There are also water systems that can be used on Earth to reduce water scarcity, and help increase water cleanliness.

Getting to space isn’t the biggest issue, because wherever we choose to explore, a major operation has to be undertaken on this planet first to get us there. Whatever endeavours we undertake to be sustainable and survive in space has implications for how sustainable we can be on Earth, both for good and for bad, as mentioned above.

So, I leave it for you to decide: do the benefits of this green technology outweigh the pollution caused thus far in trying to explore beyond Earth? Or should we stay put for now, until we have a guaranteed greener way?

About the Author: Ani Talwar is the content manager at WILD, and a Masters student studying Environmental Science at the University of York. She is passionate about environmental literature, both in a fictional and factual sense and has a published novel, Atro-City The Flood. Her other work can be found on her blog, and she can be found rambling about books and plants on her Instagram or Tumblr page, where she loves receiving questions about writing, and suggestions for new articles!