Musk, the CEO and lead designer of SpaceX, wants to “make life multiplanetary,” starting with Mars. The red planet is relatively close to the Earth and once harbored surface seas and rivers, and it still has ice and a subsurface lake. Its weather is surprisingly workable, too. Mars’ surface temperature range (–285 to 88 degrees Fahrenheit) isn’t too far off from Earth’s (–126 to 138 degrees Fahrenheit). The problem is Mars’ atmosphere now has 0.006 bar of pressure, where one bar is the standard atmospheric pressure at sea level on Earth. Not only does this mean that dangerous levels of radiation reach the surfaced unchecked, but humans need at least 0.063 bar to keep our bodily liquids from boiling (this is called the Armstrong limit). [...]
No—not any time soon. At least, that’s according to the latest look at the idea from NASA’s principal investigator for the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft, Bruce Jakosky, a space scientist at the University of Colorado, Boulder. He says the growing popularity of terraforming—driven in part by Musk—persuaded him and Christopher Edwards, a geologist also at Boulder, to gauge whether it was feasible. Their answer: No, it “is not possible using present-day technology.” In their July Nature Astronomy paper, they mention Musk directly, shooting down his idea of terraforming by nuking Mars’ polar ice caps. The amount of frozen CO2 released would not be enough to induce a runaway greenhouse effect, they argue. On July 30, Discover magazine singled out Musk in a tweet linking to the headline: “Sorry, Elon. There’s Not Enough CO2 to Terraform Mars.” [...]
If Jakosky is wrong, and Mars really does have multiple bar-equivalent of buried CO2 that we can access, we could potentially terraform Mars rapidly. “To judge from how quickly our greenhouse emissions are warming Earth, we could shift Mars into a warm climate state within 100 years,” McKay explained in his Nautilus feature. “The most efficient technique would be to produce supergreenhouse gases such as chlorofluorocarbons or, better, perfluorinated compounds, which are not toxic, do not interfere with the development of an ozone layer, and resist destruction by solar ultraviolet radiation. Curiosity has recently confirmed the presence of fluorine in the rocks on Mars, so the ingredients are all there.”
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