A grid on the floor of the RLV Hangar is filling up with pieces of Columbia debris that have been collected by workers in the field.

A grid on the floor of the RLV Hangar is filling up with pieces of Columbia debris that have been collected by workers in the field. The blue lines reflect the outline of the orbiter. The Columbia Reconstruction Project Team is identifying pieces and placing them on the grid approximating their location on the orbiter to facilitate the investigation into the accident that caused the destruction of Columbia and loss of its crew as it returned to Earth following mission STS-107. To date, about 25 percent of the orbiter has been delivered to the hangar.