Illustration by Jason Lee

The final report from the Columbia Accident Investigation Board is due this month, and NASA meanwhile is conducting its own review in preparation for a return to flight. Both are expected to point the finger at a chunk of foam insulation that struck the shuttle’s wing during launch. A series of impact tests done at the Southwest Research Institute showed that a piece of foam weighing about 1.7 pounds and moving at 779 feet per second could have dislodged or damaged one of the T-seals that separate the wing’s protective carbon panels, allowing super hot gases to seep inside the wing as Columbia reentered Earth’s atmosphere on February 1.