Jeff Hamilton was born in 1958--the same year that the National Aeronautics and Space Administration (NASA) was created--and grew up on a small farm outside Huntsville, Alabama. Fifteen miles away was NASA's Marshall Space Flight Center, where engines for the Saturn V rocket were being tested. When these tests took place, Hamilton recalled, "The ground would shake, the house would shake, the windows would rattle. I would run out into the yard, and you could feel it as a rumbling, you could feel it as a low-frequency thump in your chest, and you could see the smoke billowing up on the horizon. That was real cool, for a kid growing up on a ...