A new study might throw a wrench into plans to establish a human colony on Mars, whose surface is "more uninhabitable than previously thought." Indeed, the Red Planet is covered in a "toxic cocktail" of chemicals that, when combined with UV light, are capable of destroying any living organism, the research reveals. It centers on perchlorate, a chemical compound naturally found on Earth, where the temperature keeps it stable, and on Mars, where it can wreak havoc. Researchers at the University of Edinburgh first exposed a common bacteria found on spacecraft to UV radiation similar to that which occurs on Mars' surface. The bacteria died in about a minute, reports ZME Science. Next, researchers mixed magnesium perchlorate with the bacteria and exposed it to the same level of radiation.
This time, the bacteria died in 30 seconds. Intrigued, researchers then added iron oxides and hydrogen peroxide, both of which are found on Mars. Under UV light, the components appeared to work with the perchlorate to kill bacteria 11 times faster than just perchlorate did. What does this mean for future Mars missions? Well, there's little risk that bacteria carried by spacecraft will survive to contaminate Mars, researchers say. But life on Mars must also lie below the surface, where it's free of "reactive UV-activated perchlorates," a NASA scientist tells the Guardian. The study author suggests life may survive at depths of two to three yards. Such depths could be reached by the ExoMars rover scheduled to arrive in 2020. (Read about another fascinating discovery on Mars.)