For entry flight director Leroy Cain, struggling to make sense of unexpected telemetry from the shuttle Columbia and still hoping to regain radio contact, it was a moment of reluctant, dawning realization that a day he'd hoped would never come was finally there.

Mission operations representative Phil Engelauf, sitting directly behind Cain in mission control, had just heard that television views of Columbia high above Texas showed multiple contrails, the result of the orbiter's apparent catastrophic destruction a few moments before.

Clearly stunned, Engelauf turned to astronaut Ellen Ochoa on his right and told her the hard news. Ochoa gasped, looked up at the ceiling and muttered to herself as if saying "oh my God" or "oh, no." Engelauf then leaned across his console to Cain and passed on the same grim report. Cain's back was to the camera but he appeared to sag slightly. He lightly slapped the console a few times with pent-up, controlled emotion, straightened and turned back to face his flight control team.

"GC, Flight," he called.

"Flight, GC," the controller replied.

"Lock the doors," Cain ordered, initiating contingency procedures in mission control for the first time since the Challenger disaster 17 years before.

It is a few minutes past 9 a.m. EST on Feb 1, 2003. Columbia and its seven-member crew had just flown into history, leaving Cain and his controllers in a haze of emotion-tinged duty as the enormity of the moment sank in.

NASA released dramatic mission control video today showing Cain and his team during Columbia's re-entry, a gripping view of men and women at a moment of great crisis. At one point, Cain can be seen with tears on his face, but he somehow kept his emotions in check as he guided the team through emergency procedures.

"What I was doing right at that moment in time, I was saying a prayer and then after I did that, I knew it was time to go and take the next step," he said today. "My prayer was for the crew and for the families.

"You have to remember that even at that point, we didn't know the details of the breakup, we didn't know the details of the situation as it was. All we knew was that we had a significant event that was probably catastrophic. But in my mind, I still didn't know perhaps part of the crew module could have remained intact for some period of time, so I began to think about things like ground forces and getting people mobilized and looking for chutes and things of that nature."

A few minutes later, it became clear Columbia had suffered a non-survivable breakup.

Cain said today there was nothing the mission control team could have done to save Columbia and its crew. Even if engineers had know the shuttle's left wing had suffered fatal damage prior to entry, the ship's descent through the atmosphere could not have been modified enough to make a difference.

"Because the trajectory that we designed and the trajectory that we flew is one that by definition, from a thermal heat load, heat rate standpoint, is optimized," he said. "So we do not think that for a given, knowledge of a given hole or a breach or something of that nature, everything we know today says we're doing the best we can with the trajectory we flew."

He praised his flight controllers and Columbia's crew, saying "it was just pure joy being around them and working with them."

"Our hearts and our thoughts and our prayers go out to the crew and their families and that will continue to be with us for a very long time," he said at the beginning of today's briefing.

"I will tell you that this team, the NASA team, has great resolve. We will get through this and we will do it with the help of each other and the help of the community, our families and the rest of the agency. The public has shown us just a tremendous amount of support. ... We very much look forward to better days in the future where we will fly again and move forward."