Moving Home

Early ideas on the greening of the Red Planet. This edition published by Pan Books 1964. Cover art by W F Phillipps.

Visions of farmland extending to the horizon under a clear blue sky give a sense of comfort to most human beings.  This is our world, the place where we have our roots and where we belong.  So we can expect that colonization of another world such as Mars may not be regarded as complete until the same images fill the minds of those who may, one day, walk on the surface of the Red Planet.

We look into this subject in the latest edition of Odyssey – perhaps we could never believe another planet is truly ours until we farm the land and live on the surface unaided.  Terraforming Mars so that it would be habitable for people has been a frequent goal of the human race in both science fact and fiction.  In stories such as George O Smith’s 1976 novella Speculation, the process is started with vast quantities of soil, along with organic matter, being transported from Earth and then forming the base for terrestrial vegetation to spread gradually across the Martian surface.

An early science fiction story which discusses the prospects for terraforming the planet is Arthur C Clarke’s first published novel The Sands of Mars from 1951.  John Silvester reviewed this in Odyssey 8 and described it rightly as “a gentle story”, pointing out its prescience in suggesting a process to release oxygen from the soil as an interesting early concept of terraforming the Red Planet.

The main character in the story, written before Mariner 4 revealed the true nature of Mars in 1965, sees a surface that would have been quite plausible at the time: “all around him was the brilliant mottled green of the hardy plants that were the commonest life-form on Mars.”  Plants are “very thin but very tough, designed to catch as much sunlight as possible without losing precious water” – they don’t depend on the air like terrestrial plants, but get what they need from the ground.

However, the colonists discover a plant which gives off oxygen and proceed to cultivate it, with the hope of having a breathable atmosphere within a century.  But sadly such plants don’t actually exist on Mars.  Even so, an engineer sums up the overall aim by saying that, in the long run, it is “fatal to adapt oneself to one’s surroundings.  The thing to do is to alter your surroundings to suit you.”

Making the planet habitable might still be feasible.  In a seminal paper Terraforming Mars (JBIS, October 1982), Chris McKay, then at the Department of Astro-Geophysics of the University of Colorado, considered Mars to be the only planet in our Solar System which could be terraformed using foreseeable technology.  He argued that it could be done in two phases – first warming the surface and increasing atmospheric pressure within the order of a few hundred years, then altering the chemical composition of the atmosphere over a much longer timescale of up to 100,000 years.

When quoting him in their popular 2001 book Mars: The Inside Story of the Red Planet, Heather Couper and Nigel Henbest suggest that he hopes that the process could be speeded up by pumping the Martian atmosphere full of the gases that are creating the greenhouse effect on Earth.  Warming Mars within a century using “super-greenhouse gases” is, as they say, “the stuff of nightmares for environmentalists on Earth”, but could achieve the desired results up there.

The passion amongst some to attempt terraforming is clear in several of the works they quote, originating with Michael Allaby and James Lovelock’s The Greening of Mars from 1984, though they also raise the highly pertinent warning from Clarke in his 1994 book The Snows of Olympus: “Terraform Mars?  Well, I hope we’ve terraformed Earth first.”  And there’s a key point – humanity hasn’t done so well in making sure that our current planet is maintained fit for purpose to support life, so we must have at least some doubts that we could do so much better elsewhere.

Richard Hayes, Assistant Editor (Odyssey)

Be sociable; support the BIS!