Science ---------------Columbia Disaster: What Happened, What NASA Learned

Columbia Disaster: What Happened, What NASA Learned

On Feb. 1, 2003, space shuttle Columbia broke up as it returned to Earth, killing the seven astronauts on board. NASA suspended space shuttle flights for more than two years as it investigated the disaster.
An investigation board determined that a large piece of foam fell from the shuttle's external tank and fatally breached the spacecraft wing. This problem with foam had been known for years, and NASA came under intense scrutiny in Congress and in the media for allowing the situation to continue.

Columbia, on mission STS-107, left Earth for the last time on Jan. 16, 2003. At the time, the shuttle program was focused on building the International Space Station. However, STS-107 stood apart as it emphasized pure research.

The seven-member crew — Rick Husband, commander; Michael Anderson, payload commander; David Brown, mission specialist; Kalpana Chawla, mission specialist; Laurel Clark, mission specialist; William McCool, pilot; Ilan Ramon, payload specialist from the Israeli Space Agency — spent 24 hours a day doing science experiments in two shifts. They performed around 80 experiments in life sciences, material sciences, fluid physics and other matters.


During the crew's 16 days in space, NASA was investigating a foam strike during launch. About 82 seconds after Columbia left the ground, a piece of foam fell from a "bipod ramp" that was part of a structure that attached the external tank to the shuttle. Video from the launch appeared to show the foam striking Columbia's left wing.
Several people within NASA pushed to get pictures of the breached wing in orbit. The Department of Defense was reportedly prepared to use its orbital spy cameras to get a closer look. However, NASA officials in charge declined the offer, according to the Columbia Accident Investigation Board (CAIB) and "Comm Check," a book about the disaster.


On Feb. 1, 2003, the shuttle made its usual landing approach to the Kennedy Space Center. Just before 9 a.m. EST, however, abnormal readings showed up at Mission Control. They lost temperature readings from sensors located on the left wing. Then, tire pressure readings from the left side also vanished.
The Capcom, or spacecraft communicator, called up to Columbia to discuss the tire pressure readings. At 8:59:32 a.m., Husband called back from Columbia: "Roger," followed by a word that was cut off in mid-sentence.
At that point, Columbia was near Dallas, travelling 18 times the speed of sound and still 200,700 feet (61,170 meters) above the ground. Mission Control made several attempts to get in touch with the astronauts, with no success.
It was later found that a hole on the left wing allowed atmospheric gases to bleed into the shuttle as it went through its fiery re-entry, leading to the loss of the sensors and eventually, Columbia itself.


Searching for debris
Twelve minutes later, when Columbia should have been making its final approach to the runway, a mission controller received a phone call. The caller said a television network was showing video of the shuttle breaking up in the sky.
Shortly afterward, NASA declared a space shuttle "contingency" and sent search and rescue teams to the suspected debris sites in Texas and later, Louisiana. Later that day, NASA declared the astronauts lost.
“This is indeed a tragic day for the NASA family, for the families of the astronauts who flew on STS-107, and likewise is tragic for the nation,” stated NASA's administrator at the time, Sean O’Keefe.





The search for debris took weeks, as it was shed over a field of some 2,000 square miles (5,180 square kilometers) in east Texas alone. NASA eventually recovered 84,000 pieces, representing nearly 40 percent of Columbia. Among them were the crew remains, which were identified with DNA.



Much later, in 2008, NASA released a crew survival report detailing the Columbia crew's last few minutes. The astronauts probably survived the initial breakup of Columbia, but lost consciousness in seconds after the cabin lost pressure and then died as it disintegrated.




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