I listened to two talks in September that blurred together and definitely inspired me to think more about human colonisation of space, and in particular whether space stations or the surface of planets/moons would be better locations.

Colonisation is an old science fiction theme, almost to the point of having become hackneyed without careful thought and handling of the topic. One of the earliest books I came across on this subject as a young was Robert Silverberg’s ‘The Seed of Earth’ – the fact that it is still on my shelf is just nostalgia because, despite being written by a Grand Master of SF who I respect highly, overall it is a shallow tale with poor characterisation.

I fared much better with James Blish’s ‘A Case of Conscience’, which is an excellent moral tale. Meanwhile, Silverberg’s ‘Downward to the Earth’ felt surreal and underwhelming, despite some comparisons to Conrad’s ‘Heart of Darkness’. So far, a bit bland, but then I hit a productive seam including Heinlein’s ‘The Moon is a Harsh Mistress’ (moon colony), Harrison’s ‘Deathworld’ (again, somewhat surreal) and Clarke’s ‘The Sands of Mars’… but something still felt lacking…

… and then we hit 2 series of novels in the ‘modern era’ that redefined what a good space colonisation story could be. They felt both possible and realistic visions of what the future could be like with humans in space.

The first was Kim Stanley Robinson’s ‘Mars series’, of which ‘Red Mars’ is clearly the most believable, with the credibility quotient then dropping as we read through ‘Green Mars’ and then ‘Blue Mars’. Robinson’s description of how an early Mars colony could be established is excellent, and he only lets his own story down (in my opinion) by stretching fictional terra-forming beyond the bounds of believability. Even so, much of the series is extremely good, and ‘Red Mars’ is a recommended read.

The so-called ‘Expanse’ stories by James S.A. Corey give a good description of the balance of play in an inhabited solar system that encompasses Earth, Mars and the ‘Belt (ie asteroid belt).

Outside of mainstream success, I must also call out Gerald M. Kilby’s ‘Colony Mars’ series, in particular book 1, ‘Colony One Mars’. Kilby could rest his writing on the shoulders of previous writing and decades of remote exploration of Mars, with the result that the colonisation methods and sense of place feel real.

So fiction is starting to point in a more realistic direction for solar system colonisation. But is the idea just SF, or is it a practical goal?

Until I listened to the two talks I mentioned, I generally felt that colonisation was not possible, because the methods used would be too small-scale for success. Even Elon Musk’s “Starship” concept felt like a throwback to Flash Gordon stories and pipe dreams.

What I was missing was the scale that can now be achieved, using existing technologies or methods that could be advanced with only moderate effort.

The first talk that has changed my mind was Dr Peter Swan talking with the British Interplanetary Society about the development of Space Elevator technology. With enthusiasm, Swan talked about the construction of a 100,000 – 163,000 km long tether, that could potentially lift cargo into low-Earth orbit (LEO, or release it with a 7.76 km/s delta vee to destinations like Mars) with 70% efficiency, as compared to surface-launched rockets which deliver just 2% of their launch mass to LEO. His computations showed that 6 elevators arranged around the equator could lie 170,000 tons to LEO each year. He had other estimates that a Mars colony might need 1 million tons of equipment to be established, which would be economically impossible using rockets, but achievable using elevators.

Dr Swan said that research into appropriate materials for the tether are ongoing, but a “graphene super-laminate” has already been made in a 1 km length. He said that 20,000 layers bonded together, several tens of metres wide, would have the strength to operate as the tether, but the ongoing task is learn how to bond the layers together (or find another, better material). He spoke positively, with enthusiasm, asserting how very achievable building a space elevator would be using current materials and technologies. I left the talk feeling that he was glossing over some significant problems, but the core argument that, in principle, an elevator could be built, seemed sound.

The second talk was given by Jerry Stone FRAS, at a meeting of my local astronomy club (SEKAS), about the ‘Island Zero’ concept for space habitats. With permission from the family, Mr Stone has picked up the work that Gerald K. O’Neill (1927-1992) was doing to promote building space habitats as ‘free-floating’ structures (my phrase) instead of focussing on using planetary surfaces. In the first half of his book ‘The High Frontier’, Mr O’Neill made a good and compelling case for building ‘free-floating space stations’. They offer a more suitable (gravity) environment for humans working in space, options for construction ‘in orbit’, much reduced delta-vee requirements for moving materials and cargo, and potentially a more aesthetically pleasing environment for colonists.

Again, the ideas around colonising space using ‘space stations’ require a shift in our perception of scale – Mr Stone discussed how large structures could be built now, and then expanded later as the space colony developed. The ‘Island Zero’ / space habitats concept still felt underdeveloped to me, even after reading ‘The High Frontier’, but crucially, if working at scale, it also felt possible.

So the development of space as a viable colony location, which once languished in the worlds of science fiction, when viewed as a large-scale social-economic activity, now feels like a more realistic possibility.

A combination of space elevator(s), space habitats, and a covered colony on Mars would probably be achievable… if someone shows the willpower to do it…

… and whoever shows that willpower first will likely take control of the ‘high frontier’.