Twenty-five years after the NASA shuttle explosion that took the lives of seven astronauts, the tragedy is still fresh in the minds of many.
On Jan. 28, 1986, the space shuttle Challenger cleared the launch pad at Cape Canaveral, Fl., and powered into the morning sky. Just 73 seconds later the vessel exploded before the eyes of horrified onlookers.
All seven crew members died in the explosion, including teacher Christa McAulliffe, who won a national competition to become the first teacher in space.
School children around the country were watching in their classrooms as the tragedy unfolded.
"The teachers took us all outside. And we were all standing around, and we watched as the smoke plume went up in the sky," recalled Kari Anna Roy. "The teachers immediately just like swarmed everybody back into the classrooms."
Today there are 50 Challenger learning centers across the globe, where hundreds of thousands of children learn about space exploration.
--Originally published Jan. 28, 2011.