Remembering the Challenger 7, 25 years later

Michael J. Smith. Dick Scobee. Ronald McNair. Ellison Onizuka. Gregory Jarvis. Judith Resnik.

These six astronauts, and teacher Christa McAuliffe, were killed 25 years ago, Jan. 28, 1986, when NASA Mission STS-51-L went horribly wrong 73 seconds into its flight. The space shuttle Challenger broke apart. Its crew perished. A nation reeled in shock.

High school social studies teacher Dean Harned, 33, will never forget it. Knox County Schools were closed that day -- it had snowed -- and Harned was one of the relatively few people who actually saw the shuttle break up while watching the launch live on television. (CNN was the only network to carry it live. Many children around the country were able to watch the launch because NASA provided a broadcast feed on its TV network to schools because of McAuliffe's participation in the flight as part of the Teacher in Space program).

"I thought it was neat that a teacher was going up," Harned says. "My mom is a teacher and I thought it was really cool. I remember hearing that the shuttle had exploded and going out in the garage to tell my father. He had a look of disbelief on his face and said, 'No, no...'

"No doubt, it's our generation's Titanic moment."

The news spread quickly by 1986 standards. Within an hour, more than 86 percent of the country had heard about the accident, which occurred just after 11:39 a.m. (EST). CBS News was reporting the incident by 11:45.

An extensive investigation later determined that a faulty O-ring seal on the right solid rocket booster was responsible for the breakup of the space shuttle (it actually did not explode in the common usage of the term). An investigation by the Rogers Commission later determined that NASA had known about the potential problem with the O-rings since the late 1970s. Bitterly cold temperatures the morning of the flight also contributed to the disaster. Read about the entire incident here.

And here are a few horrifying facts you may not know. After an extensive recovery operation, NASA later learned that Challenger's flight cabin survived the initial breakup. At least two -- and likely all -- of the crew members were still alive and could have survived until the flight cabin crashed into the ocean at 204 mph about three minutes after the breakup. Three of the four Personal Egress Air Packs on the flight deck had been activated. A History Channel video provides further details.

NASA was heavily criticized for both its initial response to the disaster (officials all but avoided the press the day of the accident) and for its fatal decision to launch the shuttle under less than desirable conditions, despite warnings about the O-ring problem and other issues from engineers and others at both NASA and contractor Morton Thiokol.

The U.S. space program grounded to a halt for almost three years until Discovery launched on Sept. 29, 1988. Barbara Morgan, McAuliffe's backup who trained with her for the Challenger flight and watched the launch from Kennedy Space Center, flew on the Space Shuttle Endeavor as a mission specialist in August 2007.

Harned says the Challenger disaster was a game changer.

"That episode put to rest for generations the possibility that we would see a manned mission to Mars. After Challenger, NASA's timidity, the way it addressed the situation, they decided those dreams needed to be put on hold for awhile."

And, for a young boy, the Challenger disaster was Harned's initial brush with mortality.

"It was my first realization that we are fallible. There was something special about the first teacher in space. Christa McAuliffe represented the link to the future -- that ordinary Americans would one day go to space.

"Watching the reactions of her parents and her students, it was horrifying. Those mental images are burned in my head. It was very traumatizing."

The unedited CNN broadcast of the Challenger disaster can be seen here.

President Ronald Reagan's address to the nation on the disaster can be seen here.

CBS News's coverage following the disaster can be viewed in several parts beginning here.

An in-depth report on the disaster by NBC reporter Jay Barbree can be found here.

As President Reagan said in his memorable address, we will never forget the Challenger 7, nor the last time we saw them, moments before they "slipped the surly bonds of earth to touch the face of God."

Please feel free to leave your memories of that awful Tuesday by clicking on the comment link below.