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Technological SolutionsPhase I- EcopoiesisBombardment with NH3 rich asteroidsDusting of Polar Ice CapsNanotechnologyImplications of the “Runaway Icehouse” effectNuclear MiningWarming Mars by Space Mirrors or SolettaTerraforming Mars: A thousand roads to the same placeCourtney BairdAST 33012 / 13 / 02The current state of Mars can be summarized as “…a place that is too cold and dry for terrestrial life, bathed in lethal radiation, with an atmosphere that is too thin and ofan unsuitable composition (Fogg 1995a).” However, the present situation on Mars is not necessarily a permanent one, and it has been theorized that human intervention has the capability of radically transforming Mars through a process called terraforming. Terraforming refers to an advanced state of planetary engineering that could result in the creation of an Earth-like biosphere capable of sustaining human life. Although the day when humans might freely walk on Mars is still far off, preliminary technologically and biologically based plans have been formulated that may be capable of setting change into motion on a planetary scale. Technological SolutionsPhase I- EcopoiesisEcopiesis, what is generally referred to as the initial stage of the terraforming process, has been defined as (Fogg, 1995a) “…the fabrication of an uncontained, anaerobic, biosphere on the surface of a sterile planet. As such, it can represent an end in itself or be the initial stage in a more lengthy process of terraforming.” Although many proponents of ecopoiesis scenarios see crossing this first hurdle as the full extent to whichhumans should be involved in changing the Martian environment, it is almost certain that this initial barrier must be traversed if advanced terraforming is to be possible. 2Therefore, the possibilities concerning these first few steps have been mapped out most thoroughly by scientists. In general, the two most important modifications considered have been the necessity of raising mean global surface temperatures and thickening the Martian atmosphere (Fogg 1998). Affecting either one of these factors influences the others, and therefore many scenarios have been designed with the sole purpose of increasing one key environmental factor in the hopes that an alteration in one aspect will drive change in another . Other necessary alterations, which would likely be the natural result of increases in atmospheric thickness and increased mean global surface temperatures, are the stabilization of a liquid water source on the surface and the reduction of surface ultraviolet radiation caused by cosmic rays (Fogg 1998). In considering any method that attains all four of these standards, one must therefore allow for the likelihood that the outcome of planetary engineering would be subjected to a variety of feedback effects. For example, raising temperatures might release any depositsof CO2, therefore thickening the atmosphere, which thereby decreases UV radiation, which also increases surface pressure to allow liquid to be stable on the surface. One must therefore undertake the difficult task of planning for all possibilities in advance-- an experiment with variables of planetary proportions. Runaway Greenhouse scenariosThe most well known concept, that of capitalizing upon a runaway greenhouse effect, has been the subject of much debate. It is thought that an initial surface warming would could release enough CO2 from the surface (in the regolith or polar ice caps) to surmount the threshold that would cause a runaway greenhouse effect (Sagan 1973, Fogg 31998, Levine 1993, Marinova et al. 2000, Zubrin and McKay 1997). This would be donein the hopes of causing atmospheric heating and growth to become a self-driving process.Thus, with a minimal amount of heating, Mars might be characterized by a higher surfacepressure that could support liquid water, and the a thicker atmosphere to provide shielding from cosmic rays. However, the method of attaining this initial heating is the subject of some debate. It is thought the runaway greenhouse effect could be produced by releasing gasses into the air. The gasses, either CFCs or PFCs would be manufactured on the surface and released from factories (Marinova et al. 2000). However, there are several problems with the hypothesis that are unable to be resolved based upon current knowledge of Mars. For example, it has been speculated that CFCs might not be stable or long lived in the Martian atmosphere, and that interaction with the existing gasses might not produce the desired effect (Fogg 1995a). These gasses might interfere with theproduction of an ozone layer, a basic requirement if Mars is to support any sort of organisms. Also, the cost and feasibility of establishing factories able to influence atmosphere on a planetary scale is not necessarily economically or technologically viable.Furthermore, once a warming has begun, there is no way of knowing how much it will escalate once the effect becomes self-driving. When considering such options, one must also consider the nature of the greenhouse theory in the first place. Theories of global warming have relied upon Earth data, and much of the theory is hypothetical to begin with. It would seem ill advised to undertake any sort of attempt to extrapolate what little is known about atmospheric evolution on a planetary scale under the matter has been better resolved.4Orbital MirrorsA particularly well known theory of increasing the mean global surface temperature and capitalizing on the runaway greenhouse effect would be the use of orbital mirrors to reflect solar energy down to the planet’s surface. Several variations of this idea have been proposed, using mirrors of various sizes and at times in conjunction with other technologies (Zubrin and McKay, 1993) to affect a relatively quick heating of the Martian surface. The heating could liberate C02 trapped in the regolith, as well as CO2 trapped in the polar ice caps, thereby greatly contributing to atmospheric thickness as well. The mirrors would also capitalize upon the runaway CO2 greenhouse effect, and thus the increases in temperature and atmosphere could eventually become self-driving. Due to their sheer size, the mirrors would have to be constructed in space, and the problem of amassing enough aluminum must be considered. The aluminum would have to be shipped from earth, at considerably great expense, or be mined from another


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Mt Holyoke AST 330 - Terraforming Mars

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