John Glenn is one of the biggest pr**ks I have ever met. Or more accurately, one of the biggest ones I did not want to meet. I was in one of the training buildings at JSC when Glenn was there. I was visiting and Glenn walked by. They asked me if I wanted to meet him. I said no but they stopped him anyway. I looked at Glenn and said "why are you going up on the shuttle? There is no good reason for you to. You are bumping somebody else who has been training for many years just because you want to have some fun time". He got pissed at me. Said "who the hell is this?" and whatnot. I just walked away.
The people I was with were saying they were sorry to him and that I was not an employee so they could not "fire my ass" as he had just told them to. We walked out of the building and as soon as the door closed behind us the guys I was with busted out laughing and told me that they all wanted to talk to Glenn that way.
Glenn sucks!