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Scientists have discovered new things about atmosphere and environment on Mars. They found "toxic cocktail" of chemicals that would easily kill any living organism. chemicals have been found on surface of Red Planet. The scientists, from Edinburgh University in UK, say the discovery of chemicals means the chance of finding life on Mars has fallen. The scientists are astrobiologists – they study atmosphere and environments in universe that might support life. The researchers said Mars had no Ozone layer, which means there are high levels of ultra-violet (UV) radiation. The mix of UV radiation and chemicals sterilized the Martian landscape.

The scientists tested what happens when chemicals found on Mars mix with UV radiation. They found it killed organisms very quickly. The chemicals alone were enough to kill living organisms. However, when chemicals were mixed with UV rays, mix killed organisms 11 times faster. The scientists said: "Our observations show that surface of present-day Mars is highly [harmful] to cells, caused by toxic cocktail of [chemicals] and UV radiation." They added that their research was further evidence that surface of Mars is deadly to any form of plant life. They say the chemicals and UV rays make, "much of surface and near-surface regions uninhabitable".

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