Three years after graduating from my astronomy program, I was hired to work on the Apollo Project with a group of over 40 people. The others were engineers, mathematicians, programmers, draftsmen, etc. After starting, I heard frequent references to the spacecraft's "central angle." After requesting an explanation, I had to tell them that going back to Kepler, this was properly called the true anomaly. I made a few other corrections while I designed a backup rendezvous technique and determined the characteristics of circumlunar orbits.

When the Apollo Project began to run down, I started teaching astronomy in college and running a planetarium, in which I gave lessons to everyone -- kindergarteners to senior citizens. I also wrote a planetarium show that was translated into twelve foreign languages and adopted at 260 American planetariums and several foreign facilities.

Thus I influenced not just Earth, but also the destiny of our neighboring world.