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POPSPhoenix hunt for Mars life-support systems It's incredible that even only 60 years ago we were certain that life existed on Mars. Slightly earlier, and we were convinced the 'canals' on Mars were a product of their industry. Now we continue to question whether life has ever existed on Mars.
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POPSEarth could seed Titan with life Dr Gladman's team calculated that up to 20 terrestrial rocks from a large impact on Earth would reach Titan. These would strike Titan's upper atmosphere at 10-15 km/s. At this velocity, the cruise down to the surface might be comfortable enough for microbes to survive the journey.But the news was more bleak for Europa. By contrast with the handful that hit Titan, about 100 terrestrial meteoroids hit the icy moon. "It's frustrating if you're a microbe that's been wandering the Universe for a million years to then die striking the surface of Europa," Dr Gladman mused.Asked after his presentation by one scientist whether he thought microbes would be able to survive Titan's freezing temperatures, Dr Gladman answered: "That's for you people to decide, I'm just the pizza delivery boy."
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POPSWhy we may overlook extra-terrestrial life Ammonia, for example, has many of the same properties as water. An ammonia or ammonia-water mixture, stays liquid at much colder temperatures than plain water.Hydrogen fluoride methanol, hydrogen sulfide, hydrogen chloride, and formamide have all been suggested as suitable solvents that could theoretically support alternative biochemistry. All of these “water replacements” have pros and cons when considered in our terrestrial environment. What needs to be considered is that with a radically different environment, comes radically different reactions. Water and carbon might be the very last things capable of supporting life in some extreme planetary conditions. In any case, it is not beyond the realm of feasibility that our first encounter with extra-terrestrial life will not be a solely carbon-based occasion.
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POPSLife on Mars Could be Hydrogen Peroxide Based I think if we keep looking we will eventually find life on Mars and other planets. If not, then I agree with Carl Sagan ... if humans were the only life in the universe it would "be a terrible waste of space".