In the past few months, conclusive evidence has been found that Mars once had water on its surface, but one greater question remains: Was there, or is there still, life on Mars as well? Scientists may be on the brink of answering that question with an equally conclusive 'yes', as convincing evidence has been detected by Nasa's Curiosity rover. An instrument on the rover identified spikes of methane that scientists believe may have come from bacteria-like organisms on the surface - and it could be the first alien life ever detected. Scroll down for video Nasa scientists in California have revealed evidence that suggests there is life on Mars based on readings taken by the Curiosity rover (shown). They say methane spikes on the planet could be produced by bacteria. And at the moment there is no alternative explanation for the spikes
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Nasa scientists in California have revealed evidence for life on Mars
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They say methane spikes on the planet could be produced by bacteria
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And, at the moment, there is no better explanation for the spikes
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The signs were spotted briefly occurring by one of Curiosity's instruments
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Life is the chief producer of methane on Earth, although there are many non-biological processes that can also generate the gas
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But no such process could be ruled out during tests - suggesting there may be bacteria living on or under the surface of Mars
The @placeholder authors are cautious about jumping to conclusions, but conclude that 'methanogenesis' - the formation of methane by microbial bugs known as methanogens - may be one answer to the riddle.
These Martian organics could either have formed on Mars or been delivered to @placeholder by meteorites.