It flew nine missions successfully. The successful run ended in 1986 with Shuttle mission 51-L. On 28 January 1986, after days of technical problems and bad weather delays, the Challenger Space Shuttle, manned by a seven member crew, took off from the Kennedy Space Center. Seventy three seconds later, it exploded mid-air as the people watched helplessly.
The seven astronauts who died that day were - Spacecraft Commander Francis Scobee, Captain Michael Smith, Mission Specialist Dr. Judith Resnik, Mission Specialist Dr. Ronald McNair, Mission Specialist Lieutenant Colonel Ellison Onizuka, Payload Specialist Gregory Jarvis, and Payload Specialist Christa McAuliffe.
Christa McAuliffe was a school teacher, who had volunteered to be a part of the mission and who had been selected from over 10,000 applicants, who applied for the new, Teacher In Space Program.
Reason of Failure
As the nation reeled under the shock of the Challenger explosion, US President Ronald Reagan appointed a commission to investigate the causes of the disaster.
This commission was presided over by William Rogers, former Secretary of State, and included some very distinguished members - Neil Armstrong, Chuck Yeager, David Acheson, Joseph Sutter, Arthur Walker, Sally Ride, Robert Hotz, Robert Rummel, Albert Wheelon, Alton Keel, Donald Kutnya, Eugene Covert, and the physicist Richard Feynman.
The latter, in particular, played an important role in proving the incredible lack of effective communication and scientific understanding between the NASA officials and the NASA space engineers, as well as the sheer inadequacy of the O-ring seals that were used in the Challenger Space Shuttle.
The O-rings, which were made of rubber, were supposed to form a seal in the shuttle's solid-fuel rocket boosters and prevent hot gases from escaping. According to NASA officials, the O-rings were flexible and highly suited to withstand extremely cold weather.
Professor Feynman proved otherwise. In a famous public stunt during the course of the investigation, he crushed an O-ring with a vise and dropped both in a glass of ice-cold water. When he removed the O-ring, it was still crushed and inflexible. Thus, rubbishing NASA's claims of the O-rings being able to withstand sub-zero temperatures.
So the O-rings, present in the Shuttle as safety factors, had in fact brought about its doom. The actual cause of the disaster was a faulty O-ring seal in the Challenger's right-side solid rocket booster (SRB) that, becoming inflexible in the cold, had failed to seal the joint tightly.
The booster rocket flames had leaked through the ineffective seal and torched the external fuel tank and dislodged the booster, igniting the liquid hydrogen and liquid oxygen fuels, hence, bringing about the explosion.
Many NASA engineers, fearing this exact sort of thing, had already on several previous occasions, expressed their dissatisfaction with the technical aspects of the Challenger Space Shuttle, but they were ignored by the NASA management.
On 27 January, some engineers had warned that the prevailing cold weather could endanger the launch, but these concerns too were not taken seriously enough. The Investigating Commission concluded that the launch should not have taken place before all the problems had been ironed out, and held the NASA officials responsible for negligence.
However, Richard Feynman was the only member of the Investigating Commission, who proposed the suspension of NASA's future programs, until a complete overhauling of its management was made and all the flaws in its internal operations were effectively dealt with.
Richard Feynman has written about his lone dissent and the opposition he faced in putting forth his recommendation, in his book 'What Do You Care What Other People Think?
His dissent was noted, and NASA, which had already suspended operations for the duration of the investigation, did not resume Missions until 28 September 1988, after the enforcement of many new, strict, safety and quality control regulations, and after some crucial design and technical changes were incorporated in the building of the new Space Shuttles.
The first NASA launch after the Challenger disaster was that of the Space Shuttle Discovery.