CAPE CANAVERAL, Fla. (AP) - New Mars discoveries are advancing the case for possible life on the red planet, past or even present.
NASA scientists reported Thursday the Mars rover Curiosity has found potential building blocks of life in an ancient lakebed. The organic molecules preserved in 3 billion-year-old bedrock suggest conditions at Mars may have once been conducive to life. That leaves open the possibility that microorganisms once populated the red planet - and still might.
Curiosity also has confirmed seasonal increases of methane in the Martian atmosphere. Researchers say they can't rule out a biological source.
Curiosity has been drilling since 2013. It previously found hints of methane and organic compounds, but these findings are the best evidence yet. More powerful spacecraft are needed to prove whether life ever existed on Mars.