In September 1967, I started working at NASA in Houston, at what was then called the Manned Spacecraft Center. I worked on Apollo missions. In November 1971, I left NASA and moved to Denver to work on the Viking Mars lander project at Martin Marietta Corporation. By the time I left NASA, Apollo was winding down. Manned spaceflight beyond Earth orbit was dying. There would be no lunar bases or missions to Mars. In a mere four years, the future...