(KCEN) -- Ten years ago today, a terrible tragedy took place over the skies of Texas.
After 16 days in space, Space Shuttle Columbia broke apart as it returned to earth for a landing in Florida.
All seven astronauts aboard Columbia were killed in the accident.
To honor their memory, as well as those of Space Shuttle Challenger and Apollo 1, NASA held a memorial this morning.
It was at the Space Mirror Memorial at Kennedy Space Center.