It doesn't seem like it could be so long ago. The Space Shuttle Challenger blew up twenty years ago tomorrow, on January 28, 1986. According to the formal description on the NASA website, things went
wrong within a fraction of a second of the launch at 11:38:00 a.m. EST, culminating when "(t)he Explosion 73 seconds after liftoff claimed crew and vehicle."
Our own mountain range, the Sangre de Cristos, contains a memorial of this event: at the northern end of the range, across the state line in Colorado, is a part of Kit Carson Peak which was re-named Challenger Point in memory of the astronauts who were lost; later another eminence in the same massif was named for Columbia.