1. Twenty-seven years ago today, on January 28, 1986, the Space Shuttle Challenger exploded during its 10th flight mission (STS-51-L), just 73 seconds after liftoff. The mission was originally scheduled to begin on January 22, 1986, but it had to be rescheduled several times before the Challenger finally departed from Kennedy Space Center in Florida on Jan. 28. After the failure of an O-ring seal on one of the shuttle’s Solid Rocket Boosters, the vessel burst into flames and exploded. The tragic events were captured during a live broadcast, and all seven crew members lost their lives.  

    Today in history: Looking back at the 1986 Challenger Shuttle disaster

    Photo: NASA