“The crew of the space shuttle Challenger honored us by the manner in which they lived their lives. We will never forget them nor the last time we saw them – this morning – as they prepared for their journey and waved goodbye, and slipped the surly bonds of Earth to touch the face of God.” –President Ronald Reagan, Jan. 28, 1986

Twenty years ago to the day, I sat in a ninth-grade geography class in Rock Hill, S.C., when someone ran down the hallway outside the room, wailing about an unspeakable disaster. A few moments later, we were watching that indelible video clip play over and over again on television – a ball of flame and then one stream of smoke in the sky that suddenly and unexpectedly split into two.  

Where have two decades gone?