Those Martian settlements sound great, but something important is missing
The Red Planet needs environmental scientists.
By ANNALEE NEWITZ
Oct 5 2016
While Elon Musk’s recent speech about the glories of Martian colonies is still echoing in our ears, we should take a moment to consider what it means to colonize a planet. It’s not just about setting up some habitat pods and sucking water out of the regolith. Acquiring food and a livable environment are just as important as manufacturing rocket fuel, which is why it made sense to make a botanist the brave hero of recent colonization epic The Martian. You might say that growing space potatoes is key to the interplanetary survival of our species.
Put another way: we need awesome rockets to get to Mars, but we need environmental science if we’re going to stay there. Colonization requires us to settle—actually settle, like my ancestors did in the 19th century wilds of Texas—in an alien ecosystem. For all we know, that ecosystem might be teeming with life. Unfortunately, colonization also requires us to destroy that alien ecosystem and replace it with one we prefer.
This is where we run headlong into the moral quandaries of our future space adventures. We can use existing environmental science to understand the nature of these quandaries. But to prepare for the ethical issues involved, it helps to have some science fiction.
Kim Stanley Robinson shaped a generation of Mars dreamers with his Red Mars trilogy, an extremely well-researched tale of how humans will prep the planet with robots before landing there and eventually use terraforming to bring back its vanished oceans. Robinson’s ideas permeate our expectations about how humans will settle Mars, but the actual terraforming part remains a question mark. Before we get excited about nuking the Red Planet’s poles to kickstart a warmer atmosphere, it’s useful to remember that we’ve actually terraformed a planet before.
In the inadvertent geoengineering experiment known as the Industrial Revolution, humans perturbed the Earth’s carbon cycle to the point where our planet has now reached the early stages of a hothouse scenario. We’re already seeing its effects in disturbed climate patterns of cooling and warming, as well as altered ocean currents and storm cycles. The inevitable results are drought and extinctions, which make it harder for us to produce food and find livable habitats.
The Industrial Revolution is turning Earth into an alien planet, at least for creatures like humans who are endemic to an icehouse environment. Homo sapiens and many other life forms alive today evolved to thrive under icehouse conditions, where the planet has polar ice caps, relatively low temperatures, and carbon at 250-350 ppm in the atmosphere. As you can see in the graphic below, the planet hasn’t always been an icehouse during its more than 4 billion years in the Solar System. But we and our ecosystems happened to evolve during millions of years of cooling, and we need to keep things chill.
To maintain the icehouse, we need another geoengineering experiment to reverse the effects of the industrial revolution. Maybe we’ll end up seeding the atmosphere with reflective particles or installing giant venetian blinds in orbit. Maybe we’ll figure out a way to induce rapid, artificial weathering. But even if all we do is slow emissions of greenhouse gases and eliminate agricultural runoff into the oceans, we’re still talking about making big changes to our energy infrastructure and farming practices.
My point is that our first geoengineering experiment didn’t exactly turn out the way we’d planned. This same type of engineering problem awaits us on Mars. Only it’s far more difficult than drawing down carbon out of the atmosphere, and it has just as many potential unintended consequences.