Scientists are on the verge of discovering whether there is life on Mars based on new data collected by NASA's Reconnaissance Orbiter.
Researchers analysing data from the spacecraft, which has been at the Red Planet's McLaughlin crater, have found evidence of an underground lake that created a wet environment and potential habitat for life.
The depth of the crater apparently once allowed underground water to flow into the crater's interior, and large, flat rocks at the bottom of the crater were found to contain carbonate and clay minerals that form in the presence of water.
The crater also has small channels originating within its walls - on a level that could have marked the surface of a lake.
A report published in Geo Science journal suggests that based on this evidence, bacteria or other microbes were or still are living under the surface of Mars.
"Taken together, the observations in McLaughlin Crater provide the best evidence for carbonate forming within a lake environment instead of being washed into a crater from outside," said Joseph Michalski, lead author of the report.
Another author, Professor John Parnell, told The Telegraph they were very close to discovering sub-surface bacteria living off hydrogen, exactly as what bacteria under the Earth's surface did.
"There can be no life on the surface of Mars because it is bathed in radiation and it's completely frozen."
"However, life in the sub surface would be protected from that."
"Unfortunately, we won't find any evidence of animals as the most complex life you might get in the sub surface would be fungi.
"But fungi aren't even that far removed from plants and animals, so I think you could say that life on Mars could be complex, but small."
Launched in 2005, the Mars Reconnaissance Orbiter and its six instruments have provided more high-resolution data about the Red Planet than all other Mars orbiters combined.
"This new report and others are continuing to reveal a more complex Mars than previously appreciated, with at least some areas more likely to reveal signs of ancient life than others," said Rich Zurek, Mars Reconnaissance Orbiter Project Scientist.
Parnell said drilling below Mars' surface would be the next step to explore if life existed on the planet.
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