What Would a Satellite City in Space Look Like?

What Would a Satellite City in Space Look Like?

When it comes to space colonisation, Mars seems the next stop for most adventurous companies or people looking to venture out into the stars. According to increasing numbers of experts, analysts and commentators, the Earth is suffering from overpopulation, humanity is destroying the environment, and we’re at risk of running out of resources. So, all things considered, our future as a species may lie outside of Earth’s atmosphere… But not necessarily quite as far away as Elon Musk or NASA might want us to dream of. Instead, we may be better off building structures within the Earth’s own orbit, like the International Space Station but on a much larger scale.

You may be surprised to hear that there already is a “space kingdom”, and that this ‘kingdom’ already has a quarter of a million residents. It’s called “Asgardia”, named after the mythical city where the Norse gods live, and it came into being in 2016. That said, Asgardia isn’t actually a city, but a single satellite – said to represent humanity’s ambitions in outer space. True, the space-based structure hasn’t been formally recognised as its own sovereign nation by the UN, but it still stands as a very literal example of a definitely outlandish concept.

As for full-fledged cities in space, mysterious UFO sightings of “floating cities” have reportedly already been filmed, including one especially bizarre sighting of an enormous skyline supposedly stacked with skyscrapers floating high above China. Three years later, a NASA live-stream from a camera mounted on the ISS also seemed to confirm the existence of this metropolitan anomaly – although the apparently futuristic vision has since been debunked in the minds of most, explained away as a phenomenon called “fata morgana” – which happens because of the way sunlight reflects through clouds.

However, as strange as the intentions behind Asgardia and the appearances of floating illusions are, creating a city in orbit is probably much more viable than most of us would imagine. And it’s arguably a much better relocation option than going all the way to the moon or Mars. But, building what would essentially be the ISS on steroids would pose its fair share of problems, too.

For a start, there’s the increasing concerns over space debris. Earth’s orbit is full of trash. Over 300,000 pieces of it, according to the highest counts – including shards of metal from past space missions and deactivated satellites. Most of it’s made up of very small items – as only 19,000 pieces are said to be larger than a softball. But so-called ‘space junk’ is already an issue for the ISS, mostly because of the sheer speed it travels at. Anything orbiting at ISS level needs to be motoring at roughly 17,000 mph – so the risk of very high-speed crashes is constant, and potentially life-threatening. Currently, if there’s a higher than 1 in 100,000 chance that something could smash into the Space Station, then it has to be carefully deflected or moved to safety. Now, stick an entire city up there, and dodging space junk becomes even harder. To reliably ensure our safety, we’d surely need some sort of science fiction forcefield.

Gravity is another big problem. On the ISS, the microgravity leads to weakened bones and other complications over time. For us to live in space permanently, we’d absolutely need some similarly sci-fi form of artificial gravity. Theoretically, we could use rotational forces to simulate gravity, by using an enormous, rotating centrifuge to keep everything firmly on the ground. The bigger the object, the less rotations it’d require and the less nauseous people would probably feel… So, the fact we’re dealing with a huge, orbital city does help to an extent. The tech needed to even begin building such a mechanism is beyond us at the moment, but the idea is there at least!

So, that’s gravity solved. Sort of. But, what about the radiation? On Earth we have the atmosphere, which protects us from the vast majority of solar radiation. Out in space, no such luck. As well as the damage caused by too much microgravity, increased radiation exposure is the other major factor that limits how much time astronauts can currently spend on the ISS. The Space Station uses aluminium to protect itself from radiation, but even that winds up damaged after prolonged exposure, requiring regular maintenance and replacement. The good news is that NASA has been researching radiation for a long, long time, and while their efforts are reportedly costing them an average of $28 million a year, they have made headway. Lead researchers speculate that we may have a way to lessen the effects of radiation as soon as 2024, most likely with some sort of anti-radiation drug. If that’s the case, then our space city inhabitants would all need well-stocked medicine cabinets.

So, there are at least some solutions for the potential stumbling blocks of radiation, gravity and space debris. But the final issue is arguably the largest of all; resources. Creating a completely self-sufficient and safely-enclosed space-based society is clearly no mean feat. To live, we’d need a consistent and reliable supply of food, water, and oxygen, at least. We’d also need a steady supply of sunlight, but that part should be pretty easy to achieve.

NASA are currently working on a method to recycle the carbon dioxide we breathe out and pump it back into the air as oxygen, but the abundancy of CO2 still remains a significant problem on the ISS. It’s manageable on one space station, but could prove a major concern for any larger scale project. However, seeing as Earth’s atmosphere actually consists mostly of nitrogen – which we can recycle – there’s perhaps not that far to go until we have an endless supply of breathable air. As for water, this can also be created in space, as well as being potentially mined from passing asteroids and delivered from Earth via supply drops. Other resources, like construction materials, might also be taken from asteroids, or even from the moon – theoretically, at least. And if all else fails, we could always try recycling some of that pesky space junk.

Clearly, the list of possible problems that a satellite city in space throws up is a pretty long one. But, theories and/or actual solutions already exist on how to overcome them. In fact, many of the answers have existed for decades. Celebrated physicist Gerard K. O’Neill has been especially credited with properly working out the kinks in orbital colony theories. Way back in the early 1970s, he and his students at Princeton were leading lights for future space travel. A safe-haven for endangered species, a refuge for environmental disaster, all while being at the forefront of technology: this was O’Neill’s vision for space cities, and arguably the only reason it wasn’t realised sooner is because nobody wanted to fund it. NASA weren’t interested in such a costly venture, and we didn’t have companies like SpaceX to come to the rescue back then. But, today, much of O’Neill’s science still holds up. And with space colonisation ideas once again fuelling our imaginations, we could be populating our planet’s orbit in the now not-so-distant future.

Many remain convinced that the fate of humanity lies on Mars. But, maybe Mars is too lofty a goal for the time being. On the Red Planet, colonists would be completely alone, unable to efficiently trade with Earth or receive supplies. Vast, cylindrical space stations powered with centrifuges and solar energy, on the other hand, feel a much more feasible future. There’s some speculation that we’ll see such structures within the next century – even as early as the year 2100. Only time will tell, but clearly we’re aiming for the stars – and we might just get there!