Because it would be cool! Also, it has narrative potential.

I like Space. In both the galactic and personal sense (this is about the former). Who wouldn’t love the idea of exploring and settling alien worlds? It’s the next obvious step in humanity’s journey and would open up a near-infinite pool of resources. But space bases and colonies need liveable environments, not depressing and cramped bunkers. The practical solution to the inhospitality of every other planet and moon in the Solar System (except maybe Titan) is para-terraforming, building giant domes with controlled environments. That’s probably how most space colonies will look (in a few hundred years or so), but it doesn’t have the same sci-fi appeal as full-blown terraforming: making other planets Earth-like.

I’m not a scientist and do not know what the terraforming process will actually involve. I can report only what I’ve read online and in various forums. Nevertheless, it’s a topic I love. I think about it endlessly, not for its own sake but because the idea of bringing the world of science fiction into reality has endless narrative potential. I think that’s probably why a lot of people find the idea inherently appealing. Sci-fi is intrinsically focused on imagining a new era of human achievement and exploration. In fact, Sci-fi stories have inspired a lot of real-world technology. The hypothetical settlement and transformation of the Solar System, meanwhile, is a near-endless gold mine for short stories, novels and daydreaming. There are a lot of worlds to settle and a lot of stories to be told about them. So, let’s talk about the possibilities.

Whenever terraforming is discussed, there tend to be three possible responses. Some people (my kind of people) are immediately into the idea. Others passively listen but don’t care; fair enough. But, invariably, one or two people will exhibit grinch-like behaviour and say something akin to “I think we should focus on saving this planet first”. Why do you have to take my nerdy daydreams away, guys? I don’t try to ruin your hobbies. Personal grievance aside, it strikes me as a weird argument. I’m not saying that we shouldn’t also sort out Earth. Nor am I suggesting that we divert resources away from Earth. It’ll be a long time before we start terraforming other planets. No one is suggesting that we start tomorrow. Besides, learning about the environments of other planets will probably improve our understanding of Earth. For example, Venus is characterised by a runaway form of global warming. Still, I have a simple answer for all the terraforming naysayers: the Moon! Okay, hear me out.

The Moon

Terraforming the Moon, compared to other worlds, would be simple. First, we need to capture 100 ice comets in the Kyper Belt and drag them back to Earth. I will admit that the term “simple” is doing quite a lot of work here. Then, they need to be exploded above the surface of the Moon. This would introduce liquid water to the surface and create a suitably dense atmosphere. Easy (sort of). Creating soil and a biosphere (and probably some other steps) will still be necessary, but the hardest bit is done. If the comets are destroyed in the right location, we can even break the Moon’s tidal lock and introduce a tilt. This will create seasons and a day-night cycle.

You’re probably sceptical, and so was I at first. The Moon’s gravity isn’t strong enough to retain an atmosphere. But that’s probably okay. The rate of atmospheric loss will be meaningless on any human time scale. The Moon’s new atmosphere will take thousands of years to dissipate. All we have to do is top it up occasionally (with more ice comets). All my scepticism was resolved by one point: an earth-like atmosphere combined with the Moon’s low gravity would mean that, if you strapped sheets to your arms and flapped like a bird, you could fly! For this reason alone, I have set aside all my doubts and wholeheartedly embraced the plan. If being able to fly doesn’t get even the sceptics excited by terraforming, I don’t know what will.

Mars

After the Moon, the most obvious target for terraforming (the one that’s always talked about) is Mars. There have been a lot of suggestions on how to terraform Mars, like nuking the ice caps. My favourite suggestion, and probably the most sensible (a term that is also doing a lot of work), comes from the YoutTube channel Kurzgesagt. They suggest using a grant space laser (I’m already on board) to melt the surface, releasing the oxygen that’s chemically bonded with the rock and thereby creating a thin, flammable, but nevertheless survivable, atmosphere. This would simultaneously melt the ice caps and create a shallow ocean. It would also, presumably, destroy any chance of finding fossilised alien life, but I digress.

I like this idea on three counts. First, it would reduce the amount of material that needs to be shipped in from the rest of the Solar System. We’d still need to import a bit, but the burden is much lighter. Freeing up resources for other terraforming processes. Second, a noticeable amount of progress could be made within a single human life span. We’d spend about 50 years melting the surface. We’d still need several hundred more years to complete the terraforming process. But that rate of progress can’t be passed up. A powerful electromagnet would be placed in the Mars L1 point (a place of gravitational balance between Mars and the Sun) to protect its new atmosphere from solar winds. Third, this plan involves a giant space laser! Which advocates for itself.

Venus

Despite the fascination that Mars elicits, Venus is probably a better candidate for terraforming (let’s do both). It’s closer to Earth, at least when the orbits are right, and is similar in size. That’ll make the gravity more comfortable. Moreover, it doesn’t require off-planetary resources like other planets do. Most worlds have a long list of elements that need to be introduced, like atmospheric gasses. But Venus has too much atmospheric gas! The challenge here is to remove the bulk of its CO2-heavy atmosphere, reducing its immense surface pressure and run-away greenhouse effect. Kurzgesagt recommends blotting out the Sun with a giant mirror in order to freeze the Venusian atmosphere. The frozen CO2 can then be mined away and shot into space. This will actually give a wealth of resources with which to boost the terraforming of other planets.

Other Moons

That’s three new worlds: the Moon, Mars and Venus. And it needn’t stop there; what about the Galilean Moons of Jupiter? I’m slightly obsessed with Jupiter’s moons. Four entire worlds, just a few days away from each other. That said, terraforming them might pose some trouble. Most of them are ice moons with sub-ice mantles of liquid water. Warming up the moons Callisto, Ganymede, and Europa would create unfathomable deep ocean worlds. The ocean of Ganymede is so deep that there is warm ice at the bottom. It’s kept in solid form by the sheer weight of the water above.

Many of the forum discussions I’ve seen subsequently oppose terraforming these moons. They tend to suggest para-terraforming instead, keeping the ice surface intact. Still, my enthusiasm is unabated. I want to terraform them anyway and have little to no justification for doing so. We’ll just have floating towns or something. The only Galilean Moon I don’t want to terraform is Io, which might be the worst place in the Solar System. There’s a small radiation problem on a lot of moons, but the radiation on Io is so intense that you’d probably die immediately.

Conversely, the nicest place in the Solar System (aside from Earth) is Saturn’s moon Titan. You would still need an oxygen mask and some (very) warm clothes, but Titan is probably the only world that doesn’t need to be terraformed. Its atmospheric pressure is tolerable, and it even has rivers and lakes of liquid methane (it practically rains oil on Titan). But it’s generally quite a benign and safe world (so long as you have some domed habitats). Also, the above-mentioned flying ability is possible here as well. It’d be a shame to ruin all that by melting the rock-hard ice surface and creating yet another ocean world. Domes will serve for Titan.

Neptune

There are more moons and planets I could talk about, though I’ve covered the largest moons. The last terraforming opportunity I’ll mention is Neptune. This one is a bit out there, but it’s been speculated that Neptune’s core might be an Earth-sized rock. This means that if all the gas was removed, there could be an Earth-like planet, with Earth-like gravity, in the outer Solar System. I’ll admit that removing the gasses of Neptune will be several orders of magnitude more difficult than removing the excess atmosphere of Venus. I don’t even know where we would start. But, like I said, this isn’t something we’d be doing tomorrow. Technology will get better and, eventually, enable us to terraform Neptune!

Final comments

I don’t really know if this belongs on a blog about video games, comic book movies, and fan theories. But then, regardless of whether or not any of this could be done, the world-building potential is great (pun not intended). As above, there are a lot of great stories to be told about the terraforming of the Solar System. A lot have been told already and a lot more will be told. I have a few story ideas myself.

-Dexter