NASA WEB · Life on Mars? The notion may not be so far-fetched after all. A year after reporting that NASA’s Curiosity rover had found no evidence of methane gas on Mars, all but dashing hopes that organisms might be living there now, scientists reversed themselves this month. Curiosity has now recorded a burst of methane that lasted at least two months.

Life on Mars? The notion may not be so far-fetched after all. A year after reporting that NASA’s Curiosity rover had found no evidence of methane gas on Mars, all but dashing hopes that organisms might be living there now, scientists reversed themselves this month. Curiosity has now recorded a burst of methane that lasted at least two months.

For now, scientists have just two possible explanations for the methane. One is that it is the waste product of certain living microb...

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