The year 2003 had been anticipated as a centennial celebration of powered flight, yet it opened with national mourning. On 1 February, Space Shuttle Columbia—first of the orbiters to fly, veteran of 27 missions, and namesake of the first American vessel to circumnavigate the globe—was lost during reentry, sixteen minutes before its scheduled landing at Kennedy Space Center. The STS-107 crew of seven—Commander Rick D. Husband, Pilot William C. McCool, Mission Specialists Michael P. Anderson, David M. Brown, Kalpana Chawla, and Laurel B. Clark, and Payload Specialist Ilan Ramon of Israel—had spent sixteen days conducting cutting-edge science. The Columbia Accident Investigation Board, established within hours of the loss, determined that a piece of insulating foam from the External Tank’s left bipod ramp had struck the leading edge of the left wing during ascent, breaching the Thermal Protection System. During reentry, superheated air penetrated the wing, melting its aluminum structure from within until aerodynamic forces tore the orbiter apart. The CAIB’s August 2003 report found that the accident was not random but rooted in organizational practices and unreasonable expectations that had accumulated across the program’s history. Columbia’s sacrifice led to sweeping reforms in safety oversight and set the terms for a renewed national debate on the purpose of human exploration.