Posts Tagged ‘Greenhouse Effect’

David A. Hardy on Terraforming the Solar System

December 31, 2016

As well as colonising the other planets in the solar system with self-contained, sealed environments to protect their future human inhabitants, it may also one day be possible to terraform them. This means transforming them from their currently hostile conditions to an Earthlike environment. At the moment, the planet considered most suitable for terraforming is Mars, because of all the planets it seems to present the least obstacles to this form of planetary engineering. I can remember reading a piece in the Sunday Express way back in the 1980s, which discussed James Lovelock’s suggestions for creating an earthlike atmosphere on the Red Planet. Lovelock is the creator of the Gaia hypothesis, the theory that Earth’s biosphere acts like a gigantic, self-regulating organism. This became a favourite of several of the New Age neo-pagan religions in the 1990s, where it was incorporated into worship of the Earth Mother. Lovelock believed that while nuclear weapons were a serious danger to all life on Earth, they could be used creatively on Mars to produce an environment that would support life. Mars has large amounts of carbon dioxide locked up at its polar regions in the form of dry ice. he believed that this could be melted using nuclear missiles. Specially targeted nuclear explosions would cover the polar regions with an insulating layer of soil. This would keep the heat in, which is currently radiated back into space, reflected by the white ice. The rise in temperature would cause the dry ice to sublimate into carbon dioxide gas. This would then start a greenhouse effect, which would see more carbon dioxide and other gases released into the Martian atmosphere. This would eventually create an environment, where the atmosphere was thick enough for humans to be able to move around without space suits. They would, however, still need oxygen masks and tanks to be able to breathe. Lovelock was extremely optimistic about how many weapons would be needed. He believed that you’d only need four, if I remember correctly.

Lovelock’s ideas are wrong, but other scientists and Science Fiction writers have also suggested ways of transforming the Red Planet into a place where life can thrive. Back in the 1990s, Kim Stanley Robinson wrote a trilogy of books set on a Mars that was being colonised and terraformed by humanity, beginning with Red Mars. The veteran SF writer, Arthur C. Clarke, also produced a book in which he used to a computer programme to show what Mars may look like as it’s being terraformed. Over hundreds, perhaps even a thousand years, rivers, seas and oceans develop and green spreads over its land surface as vegetation begins growing on its previously barren surface.

David A. Hardy, the space artist, who has illustrated a number of books on space, including several with the late Patrick Moore, also described the various ways in which the Moon, as well as Mercury, Venus and Mars, could be terraformed in his 1981 book, Atlas of the Solar System (Kingswood, Surrey: World’s Work). He writes

Taking the concept of manned bases on other planets still further, there is the staggering possibility of ‘planetary engineering’ or terraforming – a term coined in 1942 by science fiction writer Jack Williamson. The idea is simply to make other worlds habitable by humans. An early suggestion, in 1961, by Carl Sagan was to ‘seed’ the atmosphere of Venus with blue-green algae, converting the carbon dioxide into oxygen and at the same time reducing the pressure and temperature (by eliminating the greenhouse effect). The upper clouds would condense and rain would fall, forming oceans.

A more recent alternative, now that we know how hostile Venus really is, is to ferry in ice asteroids 15 km or so in diameter, put them into orbit around Venus and aim them, using rocket jets, at a specific spot on the surface. Each crashes at nearly 100 km/s, at such an angle that Venus’ rotation is increased until a 24-hour day is approached, while at the same time water is provided as the ice melts. Then the atmosphere is seeded with blue-green algae.

The same could even be done with the Moon: once given a breathable atmosphere by baking oxygen out of the rocks with giant parabolic mirrors, it would remain for thousands of years, even if not replenished. The time factor for the operation is remarkably short. Mercury would need to be shielded from the Sun by a ‘parasol’ of rocky particles put up by mass-driver, or by a man-made ring. Mars would need to be warmed up, perhaps by reflecting sunlight on to the poles with huge, thin metal-foil mirrors, increasing the energy-flow at the poles by 20 per cent. or we could spread dark material from its carbonaceous moons on them with a mass-driver. Rich not only in carbon but in oxygen, nitrogen and hydrogen, this is excellent raw material for fertiliser. One the atmosphere was thickened, the greenhouse effect and carefully chosen plant life should do the rest. (pp. 86-7).

The process of transforming these planets into habitable worlds would take quite a long time – decades, if not centuries, and at present it is the stuff of science fiction. But I hope that there will be a time when we can move out from Earth to create new homes for life and civilisation on these worlds.

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