Changing Planet

Should we attempt to set up a self-sustaining city of a million people on Mars?

Stay on Earth and eventually be doomed by some extinction event [such as a massive meteor impact like the one that wiped out the dinosaurs], or become a space-bearing civilization and multi-planetary species, starting perhaps with a self-sustaining city on Mars within this century? That’s the proposition by SpaceX CEO Elon Musk in a commentary published today in the journal New Space. SpaceX, a California-based company that designs, manufactures and launches advanced rockets and spacecraft, was founded in 2002 to revolutionize space technology, with the ultimate goal of enabling people to live on other planets.

Artist impression of a Mars settlement. Credit: NASA Ames Research Center

In a detailed discussion of the technology, financing and logistics of what it would take to colonize the Red Planet, Musk suggests that the threshold on Mars for a self-sustaining city or civilization would be a million people, perhaps requiring a thousand reusable inter-planetary spaceships shuttling between a hundred and 200 people per trip over a period of 40-100 years. That implies that a colony of a million Earthlings on Mars could be built by as early as 2057, when the United Nations estimates the human population will be around 10 billion.

But not everyone agrees that such an effort would be worth the massive investment.

Colonize Earth First

Exploration is good, but it does boil down to cost, National Geographic Explorer-in-Residence Bob Ballard said at last week’s Explorers Festival in Washington, D.C. “NASA’s budget is a thousand times larger than NOAA’s exploration budget, so it’s really [about] money. Yes, we should do every kind of exploration we can, but I’m really focused on my own planet. Knowing how little of it has been explored, that 95 percent of the human race lives on less than 5 percent of Planet Earth, I would rather colonize Earth first.”

Canadian astronaut Chris Hadfield said at the same event: “Historically, we have explored for three different reasons. One is ideological…a strong core belief, religion or anything else, that leads to exploration…Or it is purely scientific, and that drives some of the current exploration going on. Or the main reason we have ever explored has been financial — it’s why the Portuguese invented all the things they did to get us around Africa, and then with the Spaniards, across the Atlantic, and then across the North Atlantic and the Northwest Passage — and it’s still driving us today. If we look at 10,000 years, or 300,000 years of exploration for our species, of those three historic drivers, and the balance between the three, financial almost always end up being the main discriminator. Where does Mars fit into that?”

While being a big fan of Musk, Hadfield added, “I think it’s his form of ideology that is pushing” the exploration of Mars. “I don’t think that it is going to be financially viable, and what he’s doing is not scientific. The scientific exploration of Mars does not involve settlement and colonization. So I think that as an ideology and a way to motivate people it’s a wonderful idea, and it’s a long-term motivator because we need our young folks to do something that hasn’t been done before. But I don’t think the timeline is realistic.”

These fundamental questions were at the heart of an hour-long discussion, Red Planet vs. Blue Planet, at the recent National Geographic Explorers Festival in Washington, D.C. (#NatGeoFest)

The panel of prominent experts in the topic of exploration of Earth and beyond were:

The perspectives of different explorers may surprise you. Read the full debate report: Pushing the frontiers of human exploration, on Earth and beyond

Learn more:

Curiosity Mars Science Laboratory. Courtesy NASA-JPL-Caltech

What’s your view? Should humans stay on Earth and fix it for our survival, or should we try to become an inter-planetary species?

Forty years in U.S., UK, and South African media gives David Braun global perspective and experience across multiple storytelling platforms. His coverage of science, nature, politics, and technology has been published/broadcast by the BBC, CNN, NPR, AP, UPI, National Geographic, TechWeb, De Telegraaf, Travel World, and Argus South African Newspapers. He has published two books and won several journalism awards. He has 120,000 followers on social media. David Braun edits the National Geographic Society blog, hosting a global discussion on issues resonating with the Society's mission and initiatives. He also directs the Society side of the Fulbright-National Geographic Digital Storytelling Fellowship, awarded to Americans seeking the opportunity to spend nine months abroad, engaging local communities and sharing stories from the field with a global audience. Follow David on Facebook  Twitter  LinkedIn
  • Skip Toomaloo

    Let’s get to the moon first. Okay, yes (wink, wink) we were there already. Let’s do it again just to make sure.

  • Martin K Zitter

    Please tell me what might happen to human physiology after several years of living in .38g.

  • Ron

    I find it bizarre and completely backwards that people are seriously proposing trading a vibrant and still lovely world for a utterly dead and hostile rock in space, ironically giving as reason that something might happen to threaten life on the living world. That’s like saying, well even though I do have this delicious and nutritious meal before me, something might come along to ruin it. So I think I’ll just have this moldy, maggot invested carrion instead. Maybe I can clean it up, add a few spices to it.

    Certainly, there are a lot of big problems with the Earth thanks to us, so having another world would be nice. But it’s pretty crazy to pretend that Mars would somehow be preferable to earth, in ANY state of ruin. Lots more here:

  • Kay

    People walked on the moon in my parents lifetime, they haven’t in mine. I’ve seen NASA gutted over and over again, getting smaller and smaller. And throughout it all I’ve heard people making grandiose statements about space travel. This world is probably far more fascinating, but we should at least go back to the moon.

  • Charles Poynton

    There are places on Earth that are too hostile for most humans, even though they have an atmosphere with oxygen, are warm enough for comfort and have access to food and water. Before spending trillions on getting a settlement established in the infinitely more hostile environment of Mars, I suggest Musk et al spend some years in the Taklamakan in China, Gibson Desert in Australia or even Death Valley. They might then understand why humans prefer living in green and temperate places like the USA, Europe or even New Zealand.

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