In Memoriam: the Crew of the Shuttle Columbia
1 February 2003: five years ago today, the shuttle Columbia disintegrated during reentry, killing all seven on board:
The crew of STS-107. Front row, from left to right: Rick D. Husband, Kalpana Chawla, and William C. McCool. Back row, from left to right: David M. Brown, Laurel B. Clark, Michael P. Anderson, and Ilan Ramon.
Coming a little over two years after the 9/11 attacks, my first assumption was that the explosion might have been the work of terrorist sabotage. However, evidence from NASA cameras during the launch quickly indicated that foam falling from the external tank was the culprit. The big disadvantage of the Shuttle's design is that the orbiter sits beside the external tank and solid rocket boosters, instead of on top of the rocket stack, as in the Apollo/Saturn V design. It's very unlikely that any manned spacecraft fielded by NASA in the foreseeable future will use a side-by-side design. In fact, the design for the new Crew Exploration Vehicle (aka "Orion") looks very much like the Apollo/Saturn V design.