dm@BBN-VAX.ARPA (11/05/85)
From: dm@BBN-VAX.ARPA ``The Greening of Mars'' by James Lovelock and Michael Allaby Lovelock is, well, an inventor. He is famous for a couple of things -- one being predicting that Viking would find no life on Mars because the atmosphere of Mars is in chemical equilibrium (which the atmosphere of the Earth most definitely is NOT). The second was originating (with Lynn Margolis of BU) the theory (known as the Gaia Hypothesis) that, over the history of the earth, living things have adjusted the atmosphere to preserve its suitability for living things. Some evidence he cites for this is the stability of the Earth's surface temperature since the emergence of life, despite the fact that the Sun has grown steadily warmer in that time. Allaby is a science writer for the BBC. ``The Greening of Mars'' is a utopian novel, told as a history of the terraforming of Mars in the form of informal lectures given by a Martian diplomat to the passengers on a Earth-Mars ship. The trip is too expensive to be two way, so her audience is composed primarily of likely colonists. Freon, and related chemicals, it turns out, are about 1000 times more effective than carbon dioxide at producing a greenhouse effect. The terraforming of Mars is accomplished principally through atmospheric chemistry. You raise the temperature using a few tons of freon to get a suitable greenhouse effect (the freon is delivered using Minuteman missles lashed together into multi-stage rockets -- having disarmed, we don't need them any more...). The increased temperature evaporates the dry-ice snow, putting CO2 into the atmosphere, increasing the greenhouse effect yet more AND increasing the atmospheric pressure. What about the ozone layer, you ask? Well, Lovelock claims that more recent studies have shown that the affect on the ozone layer of flourocarbons is actually pretty minimal, and that some flourocarbons actually serve to INCREASE the ozone layer. Along with the freon, the missles deliver payloads of spores of algae and lichens from the high desert of Antarctica. These bacteria and algae may be able to survive the (still pretty cold) Martian greenhouse, and they do a couple of things. They are dark, so the decrease the albedo of Mars, making it absorb yet more heat from the sunlight, and they begin crunching Martian rocks to make soil (in a process that will take centuries). Their short-term use is for their albedo-reducing powers. The soil producing side-effect is nice, and the delay may not be that important, because it will probably be centuries before human habitation expands to the remotest parts of Mars... Okay, so now the Martian summer gets regularly above 0 degrees C., and almost all of the CO2 is part of the atmosphere, so the air pressure at the Martian surface is about the same as at 23000 feet. The atmosphere is almost pure CO2, but now humans can move around on the surface with just oxygen masks, not pressure suits. This transformation has taken just a few years from the dropping of the first freon canister. Now you move there and start farming. You'll have to enrich the soil you farm with chemical fertilizers and manure, of course, because the algae and lichens can't have had much effect in just a few years. You'll also have to always wear an oxygen mask when you venture out doors, but you'll be able to live (in fact, since the soil of Mars is rich in pernitrates, highly oxidized substances that will liberate oxygen at room temperature, if you're oxygen mask fails, you may be able to survive for a short period until rescued by spreading out your clothes on the ground and lying beneath them, breathing the oxygen that is liberated by your body heat). Anyway, the most interesting thing I've read about since Carl Sagan's space colonies at L-5.