'We will never forget them': NASA pays tribute to the seven Challenger astronauts 40 years after the tragedy

The National Aeronautics and Space Administration's (NASA) Office of History on Wednesday commemorated the seven astronauts who lost their lives aboard the shuttle Challenger 40 years ago, in an accident that marked a before and after in space missions.

In that regard, the office recalled President Ronald Reagan's words on the event:

"The crew of the space shuttle Challenger honored us by the manner in which they lived their lives. We will never forget them … as they … 'slipped the surly bonds of earth' to 'touch the face of God'," the former U.S. president said.

In that sense, NASA assured that "their legacy constantly guides our commitment to learning, vigilance, and safety."

The agency also recalled that on January 28, 1986, NASA and the "the American people were rocked as tragedy unfolded 73 seconds into the flight of Space Shuttle Challenger’s STS-51L mission."

According to officials, a propellant engine failed and caused the Challenger shuttle to disintegrate, claiming the lives of all seven crew members. "A piece of foam, falling from the external tank during launch, had opened a hole in one of the shuttle’s wings, leading to the breakup of the orbiter upon re-entry," NASA noted.