NASA Scientists Present Theory About Why We Haven't Met Other Intelligent Life. It's Crushing.  Yahoo News NZView Full coverage on Google News
E.T., phone Earth ... if you can.E.T., phone Earth ... if you can.

NASA Scientists Present Theory About Why We Haven't Met Other Intelligent Life. It's Crushing.

The history and current state of our own species provide some clues.The history and current state of our own species provide some clues.

NASA Has a Theory for Why Humans Might Be the Only Intelligent Life in the Universe