In October last year, NASA announced its ‘Hundred-Year Starship’ program designed to settle humans on other worlds, starting with Mars in the 2030s. It would be a one-way mission: the Mars colonists could never come home.

Writing in Scientific American (August, 2011, Letters) former astronaut Don Peterson listed the many serious problems with such a Mars Colony. He finished with a rhetorical flourish: “Most of all, why would anyone go?”

It took a while to think of a reason.

The old man lay dying on his cot in a run-down, deserted wing of the hospice. “Joanne,” he whispered as his granddaughter leaned towards him, “Joanne, I have something to tell you – something about the Mars mission I never told you before.”

So that old topic: Joanne straightened her skirt and dutifully slid the threadbare office-chair closer to the bedside. Her grandfather had been Flight Director back in 2035, responsible for the efficient execution of the mission. At first it had gone so well: three ageing astronauts successfully landed on Mars; our first space colony. It had cost a fortune to ship the habitation module, the supplies and a nuclear power plant to Mars. There would be no hope of return: the first Martians were there for life, a life which, it turned out, would be measured in days only.

On day four the nuclear power plant blew up and the nascent colony was utterly destroyed.

NASA had never understood why. Perhaps a meteor, insufficiently slowed by the thin atmosphere, had hit the reactor; perhaps an excess of cosmic radiation (there had been a solar flare at the time) had triggered an instability; or maybe they’d just been unlucky, victims of just one in a million possible engineering malfunctions. Whatever the cause, the tragedy had wrecked her grandfather’s reputation, his career and finally his health. Which was why he was now dying alone in this derelict home for the terminally-ill.

“Joanne, we always knew Mars was impossible. There’s no oxygen in the atmosphere, no easily available water and it’s colder than Antarctica. We can’t breathe there, we can’t drink and there’s no way to grow food. Humans will never colonise Mars.”

She looked at him blankly as his dry, flaky fingers grasped her hand for emphasis. Of course we would colonise Mars, otherwise what was the point in setting up the colony?

“A person requires five kilograms of oxygen, water and food to survive each day. Where were we going to get that on Mars? No, the future there is automation, smart robotics, and genetically-altered Mars-friendly life.”

“I don’t know why you even bothered in that case,” she scolded, “What was the point if Mars is so useless?”

“Didn’t say useless. It’s a whole planet, got to be good for something. Just not for earth-normal human colonists.”

He lay back on his pillow, the effort all but overcoming him.

She thought about what he had just said. So the powers-that-be back in 2035 had already come to the view that Mars could never be colonized by humans. Mars belonged to advanced robots and new forms of genetically-engineered Martian life, perhaps even successors to ourselves. But such technology wasn’t available back then and wasn’t available now. So why did we send the colony?

“We knew the colony wasn’t sustainable,” her grandfather gasped, “No point in prolonging the agony: illness, starvation, lingering death – all bad publicity.”

He paused.

“You see it now? The astronauts were criminals who had committed terrible atrocities, reprieved as they thought from execution. We doctored their files.

“There was no accident; there never was any nuclear pile – pointless and far too dangerous. We blew the colony up ourselves, Joanne, pre-planned charges. In the event, everything worked entirely to plan.”

‘Perhaps we’re all like this so close to death,’ she mused, ‘Reworking reality so as to justify our little, meaningless lives. Our parting egos buoyed aloft by comforting dreams.’

She squeezed his hand, managing to work it loose. The atmosphere suddenly felt as thin and airless as Mars itself. Joanne murmured some empty words of mock-concurrence and made to leave, conscious that this would almost certainly be the last time she saw him. As she stood up he made one last effort, tears glistening in the corners of his eyes.

“It’s ours,” he said, “It was our colony – we claimed the planet, not anyone else. Forget the UN courts; in the eyes of the world Mars is ours now, our destiny. That colony was the key stepping stone, the necessary step.”

Joanne managed a polite, synthetic smile as she backed away … “Goodbye, Grandpa …”

“Don’t you see? It set things up, gave Americans a toehold … something to prove, so that we’ll return …”

But she had already left, turning into the exit corridor without looking back.

Finding people for a one way trip to Mars wouldn’t be a problem: they’d be queuing round the block for the glory of it. No, the problem is with the economics. We either terraform Mars (prohibitively expensive) – or we ‘marsiform’ us (cheap once the genomic R&D is done, which we’ll probably do anyway) and then do the minimum required to make Mars habitable at all.

Can you imagine the politics of this in a culture which has a problem with stem cell research? I imagine there might be a few ethical scruples expressed by some politically-influential people, don’t you think? Reason enough to give Americans a solid motive to do whatever was necessary … so that they didn’t die in vain.