Elon Musk has been in the news talking about nuking Mars. Again. Sigh. This is a profoundly bad idea, and I wish someone who otherwise seems serious about actually sending humans to that planet would stop even joking about it. Not only has this been tried before, here on Earth, but on Mars it wouldn’t do nearly enough to make that planet habitable. It is a distraction. But let’s dig into why anyway.
Engineering our planet with nuclear weapons
There is, as you might expect, a little bit of history around using nukes like this that is worth perusing here. Namely, that transforming the landscape with nukes — relying on their horrific destruction to act as a sort of “easy button” for large projects — is as old as the bomb itself. This mindset was operationalized in the U.S. and Soviet Union under the concept of Peaceful Nuclear Explosions, or PNEs.
In the U.S., the government called their scheme Operation Ploughshare and from 1961 to 1977 it blew up 35 nuclear bombs seeing how nuclear bombs might be used to terraform the landscape to make it more ameliorative to industrial exploitation. The project, which Benjamin Sovacool estimated cost over $770 million, was named after the Book of Isaiah, where in chapter 2 the prophet predicts that the coming of the son of God will prompt mankind to “beat their swords into ploughshares” and give up war. The scope of the project was grandiose: nukes would widen the Panama Canal, carve railways through the Rocky Mountains, excavate harbors, and expand aquifers, even drill for natural gas.
The most viable project for Operation Ploughshare’s bombs was to stimulate natural gas production — something they tried in a trio of explosions called Gasbuggy, Rulison, and Rio Blanco. Despite public opposition, especially to the test in Rulison, Colorado, the Supreme Court declined to hear challenges to the explosions and ruled that the explosions could proceed. It was a disaster for the area.
Think of it like nuclear fracking, in that sense: it is a mechanically efficient way of breaking apart deep rock formations, but by breaking apart those rocks you destabilize the surrounding landscape which can complicate extraction. Natural gas was certainly released by these explosions, but it contained radioactive material from the bomb and thus useless in a commercial setting. The initial excitement about nuclear fracking fizzled out quickly and the experiments were never repeated. Underground nuclear explosions are not harmless, though they are less harmful than explosions in the atmosphere. These test detonations still spread spread radioactive dust into the environment, and many of the Ploughshares sites have been effectively quarantined by the Department of Energy over fears of contamination.
The U.S. finally abandoned Operation Ploughshare once it proved to be extraordinarily expensive, politically troubling because of the radiation leakage, and somewhat ineffective at its intended purpose. Put simply, individual explosions were fine, but not big enough to be useful on an industrial scale — you would have to use a lot of nukes to get the job done. Traditional excavation was more cost effective, and no one wanted a bunch of underground nuclear explosions happening near their communities.
The Soviets had their own PNE project called Nuclear Explosions for the National Economy (Ядерные взрывы для народного хозяйства, if you want to look it up). Unlike in the U.S., the scale of the Soviet testing was astonishingly broad: between 1965 and 1989 they conducted 156 PNE tests on everything from creating underground aquifers to building dams to reflective seismology. However, much like in the U.S., the tests demonstrated that containing the radiation after these explosions was difficult and often spoiled the intended results (why create a radioactive water reservoir?). The cost of drilling and setting the nuclear bombs was not low enough to make it a viable alternative to traditional excavation projects (plus the largest of the Soviet PNE detonations, Chagan, in 1965, also likely violated the Partial Test Ban Treaty of 1963). Lastly, the USSR was distinctly negligent in how it handled the communities near its test sites, and the region near Semey, Kazakhstan, where many explosions occurred, has been a cluster for radiation-induced cancer for decades.
So the whole idea of PNE was discredited and abandoned by the major nuclear powers decades ago. It is too expensive, difficult, and unpopular to bother with. Why would you want to resurrect it on Mars?
Engineering another planet with nuclear weapons
At a conceptual level, nuking Mars sounds sort of fun but only if you don’t think about it for more than a few minutes. There’s no reason to, it is heinously expensive, and won’t do the job anyway.
One of the biggest problems humans on Mars face is ionizing radiation — the planet has no magnetic shield the way Earth does (its core is too solidified to generate one), so the solar wind bathes the planet’s surface in radiation while it strips away the atmosphere. Why would you want to add more radiation into that mix? (Yes, I know, people will say modern thermonuclear warheads release relatively less radiation than older designs, but again: when radiation is already a major problem for humans on the surface why would you add to that problem?)
The scale of what is needed matters here as well. Operation Ploughshare was canceled, in part, because far too many nuclear explosions would have been needed to make the program financially viable. And that’s for something as relatively simple as fracking for gas — an industrial project we have known how to do for decades and at which we have become very good.
No one is really sure how to terraform another planet — especially not with bombs. Musk supposedly wants to nuke the planet’s polar ice caps to release water into the atmosphere and warm the planet. Melting the ice caps isn’t the worst idea, but it’s a non-starter on Mars.
Think of what it’s taken to change our own planet. Humans worked diligently for 150 years to warm the planet by about 1 degree celsius through massive, planetary industrial output. In order to just to release Mar’s frozen water and solid carbon dioxide you would have to explode thousands of nuclear warheads over many decades. And even then, it won’t matter much! Last year, Nature released a study that demonstrates Mars simply does not have enough carbon dioxide to thicken and warm the atmosphere in any meaningful way. So even if you do spend decades blowing up bombs over the Martian poles, there won’t be enough gas released to do the job. Other, less explodey options, like releasing highly engineered microbes to eat the perchlorates in the soil and release greenhouse gases that way, face similar problems of scale — you’d need to get microbes to eat the entire surface of the planet down to a depth of 100 meters to release enough gas into the atmosphere. For all intents and purposes, Mars is a vacuum — to give it an atmosphere would require a LOT of gas.
All of this is to say nothing of the monumental expense and risk of launching thousands of nuclear warheads into space. Sending thousands of nukes across interplanetary distances is hard, and things go bad and explode, and even SpaceX does not have a sufficient launch success rate to ensure that an aborted launch won’t scatter radioactive waste across Florida.
One last consideration, because even the idea of planetary scale geoengineering is a process we understand so poorly: there is also a likelihood that rapidly creating enormous clouds of superheated gas and dust in the atmosphere will have the opposite of its intended effect.
One of the big worries about global thermonuclear warfare on Earth, apart from rendering the sites of the explosions uninhabitable for centuries, is that the combined clouds, dust, and ash thrown into the atmosphere would create a nuclear winter — a concept popularized by Carl Sagan in 1983. When extensive explosions kick up so much dust and debris they can completely shroud the sun and impose an unnatural winter on the planet that disrupts ecosystems and could even ends food production. By exploding huge amounts of material to try to thicken the atmosphere, Elon Musk’s lust for cool ‘splosions might actually make the planet less habitable in the process.
Space travel is neat, but these grandiose plans are not
So why would the very smart man who founded a successful and innovative rocket company be so hung up on such a bad idea that he repeats it over and over again over the course of several years?
I don’t have a clear answer. Musk’s penchant for grandiose thinking to fire up Twitter accounts that stan him is part of his brilliance at marketing — was there any purpose to selling those not-a-flamethrowers, for example, beyond creating hype and “coolness?” I don’t mean to discount the role of marketing here (it’s a field I work in often!), but it is important to recognize the distinction between hype and reality. Nuking Mars is hype.
However, I think it’s also something else. The obsession with turning Mars into a back up planet for Earth is a driving ideology for wealthy industrialists and starry-eyed science fiction fans in the 21st century — a potent mixture that make media coverage and discussion all but inevitable vital if you need to sell stock based purely on your [personal brand!). The challenge with this thinking is that there is no back up planet for Earth — especially not Mars. It simply cannot ever replace our own home — it isn’t big enough, the atmosphere is too thin and poisonous, the ground is toxic, there’s no feasible way to guard our DNA against the solar radiation, and we have no known technology that could create a thick atmosphere and replenish the water that has been stripped away over billions of years.
Nor, let us forget, is there any viable economic argument for a space colony on any time scale — microgravity is far easier to reach in Earth orbit, but we can’t manufacture things there (or even do the laundry!) and Mars has nothing particularly valuable to export we can’t find much more easily somewhere much easier to reach and return from. The Gobi desert is far more habitable and economically productive than any Martian colony will ever be. As a destination for teams of researchers, Mars is an exciting destination. But as a colony location, it is a dud, one so awful the excitement people feel about living there is a bit worrying.
The standard rejoinder to this naysaying is “what if something destroys the Earth? Then humanity is destroyed too.” This is absolutely true — but it will still be true even if there is a Mars colony as well. Most of the disasters that could destroy the planet (solar flares, asteroids, nuclear warfare, catastrophic climate change, etc.) can be mitigated and survived by even a small population with political will, massive investment, and international diplomacy. More over, should something be unavoidable, like that terrible Moon breakup vaporizing the surface of the planet in Seveneves, it is far more feasible to survive on Earth itself (underground in caves or deep underwater, both of which happen in that book) than it is to try to survive in the even more hostile environment of space.
Maybe in some distant future a self-sustaining colony will be feasible with some pretty fundamental changes in our technological prowess, but for now it isn’t, and it won’t be for any foreseeable future. In the meantime, our current world is facing catastrophic changes and those changes are fixable. We can halt catastrophic climate change, if we want. But we, as a species, don’t want that, and neither do our billionaires.
I suspect what’s going on with all the grandiose space stuff (and sigh, I love space stuff!) is the latest manifestation of Frederic Jameson’s famous adage “it is easier to imagine the end of the world than the end of capitalism.” People like Elon Musk and Jeff Bezos think investing the enormous resources needed to build space colonies is a better use of their money than investing their resources to address climate change, de-carbonize the economy, and address grinding human poverty. Building space colonies lets them stay in charge, make decisions, dictate labor policies, and avoid taxes on their extraplanetary schemes (assuming this is ever an economically viable project at all). The political logics of this drive are, in a word, terrifying.
For many of the industrialists furiously building spaceships, they can easily imagine endgame scenarios for the planet, but not for the destructive economic system that made them unfathomably wealthy. And because they aren’t willing to compromise on their personal wealth (there’s a reason they are building spaceships through for-profit companies), they aren’t willing to do the hard work needed to forestall the very catastrophic changes they say they want to flee.
For a group that fashions themselves dreamers, the rich men who advocate despair and acceptance rather than fixing climate change are remarkably short on dreaming. De-carbonizing the economy is not some impossible pipe dream; it will just make some extraordinarily wealthy men (yes, men) less wealthy. Inequality is at the heart of climate change, and it is a structural artifact of the global economy. Changing that will be harder than building a colony on Mars — it requires more imagination, it requires more patience and persistence, and the political changes needed cannot be algorithmically programmed with grid fins to control its descent.
Earth needs us far more than Mars needs nukes. Instead of chuckling at the inane schemes tweeted out by the hyper-wealthy, let’s instead refocus on fixing what’s going wrong with our own planet first.
A generous and sincere thank you to Cheryl Rofer for helping me get the details of Operation Ploughshare right. Follow her on Twitter.