The thing I remember most about the Challenger disaster is that I'm pretty sure I had NO idea that a shuttle was being launched that particular day. Sure, there was all that "First Teacher in Space" stuff, but the thing had been postponed so many times that I frankly lost interest.
I was working at the comic book store, FantaCo, listening to my favorite radio station of all time, Q-104, when the 10-2 shift DJ, Mary Margaret (Peggy) Apple, who I knew well, stopped playing music to announce the disaster. From the little of the particulars that I remember, my sense is that she handled the story rather professionally, something she was rarely, if ever, called on to do in that job.
Later, when I gothome, I saw the pictures of the 73-second flight over and over ad nauseum uuntil I was practically nauseous. Eventually, I would learned more about O-rings than I ever thought possible.
I also remember where I was when the Columbia tragedy took place, at home getting ready for an annual MidWinter's party in the MidHudson Valley of New York State. I called my friend Mark, a real space geek and broke the news to either him or his wife Paula; they lived in the MidHudson and were going to be at the party. My first thought when I heard about it - it's the same weekend as the Challenger 17 weeks earlier! Well, not exactly, but pretty close (1/28/1986, 2/1/2003). That time, I felt even a greater sense of loss, for the Challenger disaster taught me never to take these extraordinary technological events for granted ever again.