"Devising more efficient artificial super-greenhouse gases will also make it faster," Marinova adds.Ībove: Though still an undergraduate student, Margarita Marinova is advancing our understanding of how to make Mars habitable for humans. Actually, it wouldn't take quite that long, Marinova points out, because her calculation doesn't include the feedback effect of the CO 2 that would be released as Mars got steadily warmer. "That depends," says Marinova, "on how fast we make the gases." According to rough calculations, "if you had 100 factories, each having the energy of a nuclear reactor, working for 100 years, you could warm Mars six to eight degrees." At that rate, to increase the average Martian temperature to the melting point of water - it's about minus 55 degrees Celsius now - would take about eight centuries. "Once CO 2 is released, it will take over" part of the job, and PFCs will only need to be used to plug the gaps. "When we first start warming Mars," explains Marinova, "we'll want to cover the whole spectrum" of thermal infrared radiation. A carefully chosen combination of PFCs could do the job quite handily. On Earth, there's so much CO 2 and water in the atmosphere that it doesn't matter if some infrared radiation escapes back into space.īut on Mars, terraformers will want to trap every bit of heat they can.
Greenhouse gases in the atmosphere work as a global layer of insulation, trapping that infrared radiation and preventing it from escaping into space.ĬO 2 and water are good at trapping some of this infrared energy, but not all of it. The planet absorbs this solar energy, and then re-radiates warming infrared energy back out into the atmosphere. The sunlight that hits a planet's surface arrives primarily as visible and ultraviolet light. Greenhouse gases prevent that energy from escaping into space. "You don't want to destroy ozone," says Marinova, "because it's a UV protector."Ībove: Sunlight is absorbed by a planet's surface, which then radiates warming infrared energy into the atmosphere. On Mars, building up an ozone layer in the atmosphere would be an important goal of terraformers. Ozone in Earth's atmosphere provides protection against ultraviolet (UV) radiation, which is harmful to life. Third, they do not have any negative effects on living organisms.įinally, unlike their chemical cousins, chlorofluorocarbons (CFCs), PFCs don't deplete ozone. This causes serious problems on Earth, but their longevity would be a positive factor on Mars. Marinova has been studying the warming effects of PFCs, in collaboration with Chris McKay, a member of the NASA Astrobiology Institute at the Ames Research Center. McKay was one of the organizers of the terraforming conference where Marinova presented her research. Margarita Marinova, an undergraduate student at MIT, believes she has an answer to both problems: use artificially created perfluorocarbons (PFCs) to initiate the planetary warming process. Second, the best way to get Mars to release its CO 2 spontaneously is, well. First, even if all of Mars's available CO 2 were coaxed into the atmosphere, it wouldn't necessarily warm the planet enough to make it a comfortable place for humans, because no one knows just how much CO 2 is there. Sign up for EXPRESS SCIENCE NEWS deliveryīut there are two problems. Scientists at the conference speculated how it might be possible to warm Mars just enough to evaporate the planet's available carbon dioxide (CO 2 trapped in ices and frost) into the atmosphere, where such gases could contribute to keeping the planet warm. Here on Earth, the idea of a runaway greenhouse sets off alarm bells.
One solution might be to pump enough greenhouse gases into the Martian atmosphere to create a runaway greenhouse effect. At a recent NASA-sponsored conference, "The Physics and Biology of Making Mars Habitable", scientists discussed ways that future colonists might make the frigid planet a little more comfortable.Ībove: Artists' James Graham and Kandis Elliot impression of a wetter and warmer Mars. If humans ever build communities on Mars, they might want to find a way to turn up the global thermostat. The Red Planet's mean annual temperature is 55 degrees C below zero - that's about the same as the temperature of Earth's south pole during winter. Febru- To say that Mars is a chilly place would be an understatement.
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