'Sense of Loss': Columbia Space Shuttle Crew Remembered 10 Years After Accident

"I was hard pressed to disagree. That mindset was widespread. Astronauts agreed. So don't blame an individual; look for the organizational factors that led to that kind of a mindset. Don't let them in your organization.

"After the accident," he added, "when we were reconstituting the mission management team, my words to them were, 'We are never ever going to say that there is nothing we can do.' That is hindsight."

Twelve children lost a parent on Columbia.

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Husband's daughter is a seminary student. Before his final mission he recorded Bible verses on videotape to be played back to his children while he was in space.

Israeli astronaut Ramon, a hero in his country, had a son who followed him as a fighter pilot, and who later died in a plane crash.

Iain Clark has become a young man his late mother would be proud to claim. He inherited many of her skills, is a master scuba diver and will soon be going to college.

His father, a former NASA flight surgeon, crusades for research to keep future astronauts safer on missions.

Astronauts now hunger to go to Mars, but a three-year round trip is not just a logistical and engineering challenge, it's life-threatening. There is no quick rescue.