Space shuttle Challenger exploded shortly after lift off due to a poor decision to launch below safe ambient temperature.
I'll never forget sitting in my car listening live on the radio as the announcer talked in detailed description of subfreezing temps as I sat and wondered to myself if that was necessarily safe because I felt those temps had not been previously experienced during a launch because I am a Florida native and I know how rare those kinds of temps are in Cape Canaveral. Still seems odd that a mere salesman such as myself could get that kind of uneasy premonition about it when brilliant NASA types obviously did not raise that kind of alarm within their own thoughts. I waited until the blast off and sign off from Cape Canaveral on the radio and then went inside a client's office briefly. When I came back out to the car and the radio had the launch coverage back on surprisingly and the announcer had an ominous tone I knew then that something was very wrong......and my own concerns about those low temps had been proven unfortunately to have merit.
I have that day burned into my conscience as well and can tell you where I was and all the external items that our senses perceive. I was driving down a dirt road while listening to the countdown and pulled off and walked out to wait for the liftoff and the experience of watching it pull away into space. With the radio relaying the launch in the background I could see it pick up over the horizon of trees to the northeast and watched in horror as the white cloud of smoke seperated and gave off an orange glow as the upward movement stopped. At the same time the radio stopped giving specifics on the launch and went quiet. Deep down I knew the launch went bad and watched the smoke seemingly stop in the sky. Our hope was the astronauts had somehow surived the crash in the capsule but the weight of what had just happened was almost thick with shock... What has amazed me for all these years is how the rocket plume of smoke seemed to almost sit frozen in the sky for hours and oh so slowly moved westward until disappearing hours later....