I thrive with high-performance challenges in front of me.

All indications are that three and a half billion years ago, Mars looked like Earth. It had lakes. It had rivers. It had river deltas. It had snow-capped peaks and puffy clouds and blue sky. Three and a half billion years ago, it was a happening place. The same time on Earth, that's when life started. So did life start on Mars?

I'm absolutely compelled for NASA to send international astronauts to Mars to find out if Mars ever harbored life.

John M. Grunsfeld Quotes