Building a Habitable Planet On Mars?

"Current knowledge of Mars suggests that it is possible to transform that planet into one that would be habitable by plants and microorganisms from Earth. This could be done over time-scales of a hundred years or so using technologies that we are already demonstrating, probably to our detriment, on the Earth. Should we do so?" That's not science fiction. That's astrobiologist Christopher P. McKay of the NASA Ames Research Center writing inThe Environmental Ethics of Bringing Mars to Life. NASA scientists are studying the possibility of altering the Martian atmosphere to make it habitable much like Earth. NASA has even created a website called Digital Dashboard: Build a Virtual World that allows you to practice making your own habitable planet on Mars by changing several climate forcing factors including light-dark albedo, incoming solar radiation, and greenhouse gases like methane. The website is based on global climate models developed for Martian atmospheric conditions by McKay and others at NASA. The calculations are relatively simplified, but it's not bad for conducting your own at-home experiments in terraforming. According to the NASA website, " [T]he basic Martian ingredients for plant life are available.... The three reservoirs of carbon dioxide on Mars - the atmosphere, the dry ice in the polar caps, and gas adsorbed in the soil - provide a positive feedback, since warming will outgas or melt this greenhouse gas, thickening the atmosphere further to trap more sunlight and thus dramatically accelerating Martian habitability."