the adults who would have to care for them. The atmosphere on Mars, the lack of sunlight and the low-gravity environment, they said, would cause significant health issues for the first generations of Martian children. Children’s bones developed, their cartilage formed, in direct response to the demands of gravity. Mars’s low-gravity environment would present significant problems for physiological development. (The astronauts on the International Space Station do regular exercises specifically designed to lower the risk of osteoporosis and muscular degeneration, but these astronauts are, crucially, not babies and toddlers.) Intensive physical therapy, they said, would be needed if these first Martian children were to survive on their home planet. And that was before you even started talking about children having to live their lives underground, to protect them from the planet’s much higher levels of radiation, or the problems of extreme boredom and depression that might well arise.
Neither the people advocating for human settlement of Mars nor the pediatric profession was giving much thought to the problem of children, they argued, and this needed to change.
I remembered something my son had said a few weeks previously, at a science museum we had taken him to. We were looking at an underwhelming audiovisual exhibit called “Colonizing the Cosmos,” about how the human settlement of Mars might be the ultimate means of ensuring the survival of the species. “I don’t want to go to Mars,” he had said. “It doesn’t look nice.”
He was right, I thought. It looked like a total shithole. But then again, this planet was no paradise either.
Why would we want children to be born on a distant planet, a place with an atmosphere of mostly carbon dioxide, and precious little gravity: a place for which their bodies and minds had not evolved? I knew the answer, of course: because we needed to ensure the future existence of the species, and it was to this fundamental imperative that the first generations of Martian children would be sacrificed. This necessity was taken as self-evident, beyond the scope of refutation. But was it so unacceptable that humanity should eventually run its course? Why was it so unthinkable that we ourselves—not necessarily tomorrow or the next day, but eventually—follow the same well-beaten trail toward oblivion as the dodo, the black rhinoceros, the passenger pigeon, the Javan tiger, the sea mink, the great auk, the Yangtze river dolphin, the monkey-faced bat, the Aru flying fox, and all the countless other species whom we ourselves had driven from the face of the Earth?
I thought of the fires that had been burning here in California all summer. I thought of the drought back home in Ireland, the strange heat. I thought of how my son had been in the world for five years, four of which had been the hottest in recorded history.
In their lists of reasons for establishing a “backup planet” for humanity, advocates for Mars colonization invariably included the prospect of climate change making the Earth unlivable. And yet even in the most dire projections of Earth’s future, there was no suggestion it might ever become as hostile to life as Mars, a planet with essentially no atmosphere, and on which the surface radiation levels were one hundred times that of Earth.
Earlier that summer, the US government had published a five-hundred-page draft environmental impact statement, intended to justify its freezing of fuel efficiency controls. Embedded in the statement was an acknowledgment that, based on current climate trends, average global temperatures were likely to increase by four degrees Celsius by the end of this century, an increase widely understood as disastrous by climate scientists. The statement’s position, though, was not that something needed to be done about this, but rather that regulating emissions for new cars was an essentially frivolous exercise, given that a coming climate catastrophe was already a given. This was something far uglier than the denial of the reality of climate change. This was an acknowledgment of its likely catastrophic effects, and an insistence that there was now no point in trying to mitigate them through government intervention; an argument that it was better at this point to continue the destruction unimpeded. Because there were still things to be bought and sold, money to be made. Because there was still time.
* * *
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As I was contemplating the prospect of human extinction, I realized that I was staring at the back of a man seated directly in front of me. He was wearing a black T-shirt, across the back