See an interactive tribute to the Columbia crew and the events from February 1, 2003.

He was one of three people monitoring the engines as communication with the Columbia crew was lost.

"It's a great tribute to the Columbia crew that we're flying again," he said.

They observed a moment of silence when they arrived at the camp to remember the Columbia crew.

Our mission, like that of the Columbia crew who perished, was devoted to biomedical research.

"You hope that somehow these lives were spared," she said of the Columbia crew.

Each volunteer was given a picture of the Columbia crew.

The Columbia crew should have never died; its loss was a disgrace.

If the Columbia crew had managed to land on a habitable world, it was possible that, even three decades later, there could be survivors.

Possibilities, she said, include affixing red, white and blue ribbons to the signs to pay tribute to the Columbia crew.