It's one of the biggest unanswered questions in science – if there are aliens out there, where are they hiding?
Now, scientists from the Space Research Institute in Moscow think the answer could be on Mars.
In their new study, the team discovered gas seeping from volcanic rifts on the Martian surface – suggesting the planet is not geologically dead, and instead is 'merely sleeping'.
Excitingly, the researchers suggest life could be hiding within these seeping fissures, particularly in the Alba Mons region.
'Looking for Martian life in the seeping fissures of the Alba Mons region would make a lot of sense,' said Daniel Mege, co-lead author of the study.
'If hydrothermal systems are active, they could contain the ingredients and energy needed for microorganisms to develop, and shield microorganisms from the hostile and changing environment above the surface.'
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