Here is part two of a multi-part series done for BBC about the Columbia Disaster in 2003 (knew you were alive). If you are interested in learning more all 6 parts are on youtube. Rather than explain it any further, I will let the people who were there do the talking.
If you are interested in the whole series:
Part 1 - Scientific Mission
Part 2 - Final descent - see above
Part 3 - The Aftermath
Part 4: Search for remains
Part 5: Heat resistant tiles
OR - here is the whole thing in HD - BBC Columbia Documentary