Why We Should Never Nuke Mars
published during a waxing gibbous moon.

As we set the Red Planet firmly in our sights for exploration and possible colonization, I’d like to offer a simple plea: Let’s not nuke it.


The Twin Peaks are modest-size hills to the southwest of the Mars Pathfinder landing site. Credit: NASA/JPL

Late last year, on Stephen Colbert’s late night talk show, superstar billionaire and CEO of SpaceX Elon Musk joked that the fastest way to terraform our neighbor planet Mars would be to lob nuclear missiles at its poles. The next day, both headlines and Colbert himself considered the idea something that only a supervillain could conceive. What nobody seemed to get into was just how ethically dubious such a plan might be.

One day, we could turn Mars from a cold desert planet into an inhabitable world. People have been speculating about ways to do that for nearly a century, usually using giant industrial machines or bioengineered microorganisms (or dramatic explosions) to raise the planet’s temperature and carbon dioxide levels. While many have explained how we could modify Mars’ climate, few articles have ever been written on whether or not we should. But as we set the Red Planet firmly in our sights for exploration and possible colonization, we will have to confront the ethics of terraforming.

In which case, I’d like to offer a simple plea: Let’s not nuke Mars.


We shouldn’t be in a hurry to terraform the Red Planet. Mars is a place of incomparable beauty and scientific interest, entirely different than our own world. Before we eradicate its current environment, we should study it in detail and gain a full and respectful appreciation for the planet that we seek to alter. Destroying it would not only be wasteful, it would perpetuate the worst mistakes of the past few centuries, showing that we have learned nothing from history. We like to believe our future lies in space. If that’s the case, let’s make it a future we can be proud of.

The best dramatization of the terraforming debate can be found in science fiction author Kim Stanley Robinson’s Red Mars trilogy. In the series, Martian colonizers split into warring factions, the preservationist Reds and the terraforming Greens. These two sides line up quite well with different present-day thinkers who have taken up the issue.

Arguing against terraforming are philosophers like Robert Sparrow, who suggests that such a project would be hubristic, falling into the fallacious belief that we have enough knowledge to control an entire planetary ecosystem. Any number of things could go wrong, including poisonous gases like methane or hydrogen sulfide accumulating in the Martian atmosphere; a runaway greenhouse effect accidentally getting set off; or the collapse of any biosphere we try to create. It would be a shame to simultaneously destroy Mars as it exists now and render it uninhabitable for life. Sparrow and others on the preservationist side also maintain that the Red Planet is a place of unique splendor with an intrinsic worth that terraforming would erase. Philosopher Holmes Rolston III asks us to consider environments with “formed integrity”—those with immense aesthetic, natural, or historical value—as places we should protect.

Others see this as unnecessary sentimentality. Planetary scientist Martyn Fogg points out that nature just as easily destroys beauty as creates it. Why are “asteroids and meteorites free to batter the Martian surface” while only “humans should be constrained from fulfilling their evolutionary potential” of colonizing other worlds, he asks. Other thinkers in favor of terraforming have suggested that, because of its massive scale, transforming Mars could teach us a great deal about the proper care of our own planet. Philosopher James Schwartz writes that “terraforming Mars is morally recommended insofar as it is likely to contribute to the solution of environmental problems on Earth.”

Both sides have their merit. The preservationists remind us that Mars is not simply our plaything to do with as we see fit. At the same time, I don’t think it’s inherently wrong to want to create a beautiful garden world that could offer humanity a second home and provide us with environmental lessons for our own planet.

The problem for me comes when people stress urgency. Musk’s nuclear plan was, according to him, “the fast way” of terraforming Mars (contrasted with “the slow way” of gradual warming and carbon dioxide release.) But that speedy option shouldn’t even be on the table. We should instead take as much time as possible to study the wonders of the Red Planet in their pristine state and carefully consider all the potential pitfalls of terraforming. Some will counter this argument by saying we want to avoid the extinction of life on Earth, and therefore need to rapidly get ourselves off this planet. It’s true; the sun has a limited lifetime. But its remaining years number in the billions, a.k.a. several hundred thousand times the entirety of recorded human history. Faced with such timescales, there’s no need to rush.

The past largely shapes our ideas of future space exploration. We tell romantic stories of daring adventurers from the last few centuries that colonized and tamed the New World, using this as our model for what we hope to achieve on other planets. But this is history simplified. The Age of Exploration was also an era of eradication, subjugation, and destruction. I wonder what the world would look if those conquerors had first stopped to consider what they were destroying, to take time to appreciate and understand other cultures and other places.

Check out our latest infographic to see how terraforming could turn Mars from inhabitable to habitable (and possibly back again).