Star Bound №22: A City on Mars?

Bruce McCandless III
4 min readJan 4, 2024


Kelly and Zach Weinersmith Are Fine Right Here on Earth, Thank You.

Looks nice, right?

Writing about humankind’s future in space tends to be wildly optimistic, replete with more or less serious musings on how (and when) to terraform Mars, construct orbiting space settlements, and harvest minerals from passing asteroids. For anyone who’s grown tired of wide-eyed predictions and low-level disappointment, A City on Mars: Can We Settle Space, Should We Settle Space, and Have We Really Thought This Through?, by Kelly and Zach Weinersmith, may be the book for you. The answer to all these questions, according to the Weinersmiths, is probably not — at least, not yet.

The authors — Zach’s a cartoonist, Kelly’s a biologist who studies insect parasitism — are well known for their off-kilter takes on emerging technologies. Unsurprisingly, A City on Mars is a funny book, complete with discussions of space sex (you’re going to need some equipment), space cannibalism, and inadvertently scabrous astronaut names, along with strange little drawings to illustrate a number of points. Discussing how best to construct a system of orbital missile launchers, for example, the authors point out that in order to achieve real effectiveness, launchers would need to be placed in a variety of orbits — “like GPS, but for death.”

Nevertheless, the Weinersmiths’ anti-expansionist argument is quite serious. It can be boiled down to the following general principles: Space is dangerous and unforgiving. We severely underestimate the time, money, and effort that will be involved in establishing habitations there. And human nature will not change once we leave Earth to live somewhere else.

The first couple of points are more or less obvious. We humans are, as the authors put it, “pillar[s] of liquid about two meters high, in which are suspended various moist and jiggly biological systems.” While we’ve managed to spread ourselves pretty handily around Earth, venturing upward and outward into the solar system presents numerous problems. Space is a life-killing vacuum, devoid of almost everything except harmful radiation. Lunar soil consists of electrically charged fragments of rock and glass that has a nasty tendency to slice up Earth-made fabrics and would likely do the same to human lungs. Martian dirt contains toxic perchlorates, and the planet’s atmosphere is thin and composed mostly of carbon dioxide, which is not fit for ingestion unless, say, you’re a tree. We can overcome these lethal challenges, but it’s going to take a massive effort to do it on the scale required for creating viable settlements off-planet for significant numbers of people. And even assuming we can do all this, how will such settlements be governed, and by whom? How will human beings on another world safeguard themselves against, well…themselves, and humanity’s penchant for violence, irrationality, and rampant acquisitiveness?

Now what? Photo by Photobank Kiev on Unsplash

A significant amount of the book is devoted to a study of what law might, or should, apply to space settlements and space commerce. While the Outer Space Treaty of 1967 has the virtue of longevity at this point, it’s not altogether helpful on a number of points. Thus, while nations can’t assert sovereignty over portions of, say, the Moon, nations and indeed private interests can establish bases and commence mining operations — exclusive mining operations, evidently — without violating the Treaty. In fact, U.S. law is quite explicit about this, as are the Artemis Accords, proposed by the United States and now signed on to by over thirty nations.

While the Weinersmiths are skeptical that the Moon is really all that rich in minerals — even tritium, often invoked as the new gold in a lunar Klondike — to begin with, they note with a certain degree of trepidation that there appears to be a sort of space race in the offing to claim various portions of valuable real estate at the poles of our only natural satellite. In the best segments of A City on Mars, they argue effectively for the need for a new legal framework, perhaps along the lines of the one governing nations’ use of Antarctica, to govern space development activities.

No doubt the Weinersmiths have conjured up a sort of pressure-suited straw man to argue against in A City on Mars. After all, no nation has serious plans to construct settlements of any significant size on the Moon, other planets, or in orbit. Elon Musk and Jeff Bezos can bloviate all they want: Mars is likely to remain uninhabited for at least another century, and we are a long way from building toroidal superstructures to house humans in space. On the other hand, a law-bending international scramble for real estate and resources on the Moon is not only possible in our lifetime but also, in the view of some, likely. Starting to think about ways to restrain future conflicts — possibly even armed conflicts — in such situations is both pertinent and timely. A City on Mars is going to irritate optimists. For the rest of us, though, it’s a healthy dose of skepticism to counteract claims of a rosy Martian dawn just around the celestial corner.



Bruce McCandless III

I'm an Austin-based writer trying to figure out space, science, and Texas politics. For more, see: