Signs of life on Mars? [Live video discussion]

NASA’s Curiosity rover, after drilling its very first Martian rock, has dug up evidence that Mars was once suitable for life — news that has mission scientists cheering.

“This is what we call pay dirt,� David Blake, lead scientist on the rover’s Chemistry and Mineralogy instrument, said at a news conference Tuesday.

LIVE DISCUSSION: Join us at 2 p.m. PDT

The discovery is a major milestone for the Mars Science Laboratory mission, which landed on the Red Planet Aug. 5 in search of spots that could have borne living microbes.

On its way to Mount Sharp in the middle of Gale Crater, Curiosity has been turning up a wealth of evidence that Mars could have contained living things: A water-rich environment, low acidity, elements key for Earthly life — hydrogen, carbon, oxygen, nitrogen, sulfur and phosphorus.

“We have found a habitable environment that is so benign and is so supportive of life that probably if this water was around and you had been on the planet, you would have been able to drink it,� said John Grotzinger, Curiosity’s lead scientist.

For more on the rover’s latest findings, join Science Now at 2 p.m. for a chat with Mars mission scientist Joel Hurowitz.

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