Challenger was one of five National Aeronautics and Space Administration (NASA) space shuttle orbiters to fly in space, and the only shuttle as of 2002 lost in an accident. The shuttle was named after a nineteenth-century naval vessel that explored the Atlantic and Pacific Oceans. The orbiter flew in space nine times between 1983 and 1985 on a number of missions. On its tenth flight, STS-51-L on January 28, 1986, a problem with a solid rocket booster led to an explosion that destroyed Challenger and killed its seven crewmembers. The disaster and resulting investigation grounded the shuttle fleet for more than two and a half years, and led to a number of safety improvements to the shuttle fleet.
Challenger's development began in the mid-1970s as a structural test article. The vehicle was not originally planned to fly in space, but instead was meant to allow engineers to study how orbiters would handle the stresses of flight. During these and other tests, NASA concluded that some modifications would be needed to the structure of the shuttle. NASA had planned to refit Enterprise, a shuttle orbiter built for landing tests, to fly in space, but found it would be less expensive to modify Challenger instead. Challenger's conversion into a space-rated orbiter was completed in 1982.
Challenger entered service for NASA in April 1983 on the sixth shuttle flight and the first flight by any shuttle other than Columbia, the first shuttle to fly in space. Challenger completed nine successful flights through November 1985. A summary of those flights is listed in the accompanying table.
The tenth flight of Challenger was mission STS-51-L, scheduled for January 1986. This mission attracted considerable pre-launch attention because
|CHALLENGER SHUTTLE MISSIONS|
|STS-6||1983 April 4||1983 April 9||• First mission|
|• Deployed TDRS-1 communications satellite|
|• First spacewalk from shuttle|
|STS-7||1983 June 18||1983 June 24||• First flight into space by an American woman (Sally Ride)|
|• Deployed Anik C-2 and Palapa-B1 communications satellites|
|STS-8||1983 August 30||1983 September 5||• First flight into space by an African-American (Guion Bluford Jr.)|
|• Deployed Insat-1B communications and weather satellite|
|STS-41-B||1984 February 3||1984 February 11||• First untethered spacewalks|
|• Deployed Westar-VI and Palapa-B2 communications satellites|
|• First shuttle landing at Kennedy Space Center|
|STS-41-C||1984 April 6||1984 April 13||• Retrieved and repaired the Solar Max satellite|
|• Deployed Long Duration Exposure Facility|
|STS-41-G||1984 October 5||1984 October 13||• Deployed Earth Radiation Budget satellite|
|• First spacewalk by an American woman (Kathryn Sullivan)|
|STS-51-B||1985 April 29||1985 May 6||• Spacelab-3 tested materials processing and fluid mechanics in weightlessness.|
|STS-51-F||1985 July 29||1985 August 6||• Shuttle main engine #1 shut down 5 minutes, 45 seconds after launch, forcing "abort to orbit"|
|• Spacelab-2 performed a number of astronomy and life sciences experiments|
|STS-61-A||1985 October 30||1985 November 6||• German Spacelab D-1 mission performed experiments on materials science, life science, and technology|
|• Crew included two German and one Dutch astronauts|
its seven-person crew included a civilian—Christa McAuliffe, a New Hampshire teacher who had been selected from more than 10,000 applicants to become the first teacher in space. The mission also featured the deployment of the TDRS-2 communications satellite as well as studies of Comet Halley.
The launch of Challenger on STS-51-L was originally scheduled for January 22, 1986, but postponed until January 28 because of the delayed launch of the previous shuttle mission, bad weather, and technical glitches. The morning of January 28 was very cold at Kennedy Space Center in Florida, with temperatures well below freezing. The launch was delayed two hours to allow ice on the launch pad to melt as well as to fix an unrelated technical problem. Challenger finally lifted off at 11:38 A.M. Eastern Standard Time. The launch appeared to be flawless until an explosion took place 73 seconds after liftoff, destroying the shuttle and its external fuel tank, and raining debris over the Atlantic Ocean. The two solid rocket boosters (SRBs) attached to the external tank flew free from the explosion for several seconds before launch controllers issued self-destruct commands to prevent them from crashing into populated areas. Challenger and its seven astronauts were lost in the accident, the worst in the history of the space program.
In February 1986 U.S. President Ronald Reagan established a presidential commission to investigate the disaster and recommend changes to prevent such occurrences from happening again. The commission was led by William Rogers, former secretary of state, and included a number of past and present astronauts, engineers, and scientists. The commission concluded that the disaster was caused by the failure of a rubber O-ring in a joint in one of the SRBs. The O-ring was designed to act as a seal and prevent hot gases from escaping, but the O-ring lost its flexibility in the cold temperatures the night before launch and failed to fit properly, allowing hot gases to escape. The hot gases formed a plume that, 72 seconds after launch, caused a strut connecting the SRB to the external tank to fail. A second later, this led to the structural failure of the external tank, igniting the liquid hydrogen and oxygen it carried into a fireball. The fireball itself did not cause the destruction of Challenger; instead, severe aerodynamic loads created by the external tank explosion broke the shuttle apart.
The commission recommended a number of changes to the shuttle program to improve the safety of future launches. First and foremost, the SRBs were redesigned with improved joints to prevent hot gas from leaking from them during a launch. Other improvements were made to the shuttle's main engines and brakes, and an escape system was installed that would allow astronauts to leave the shuttle while in flight in some cases. NASA also changed how it managed the shuttle program, and improved communications between engineers and managers.
The Challenger disaster grounded the shuttle fleet for more than two and a half years while the required improvements were made to the remaining orbiters. The shuttle program returned to flight with the launch of Discovery on mission STS-26 on September 29, 1988.
see also Challenger 7 (volume 3); History of Humans in Space (volume 3); Human Spaceflight Program (volume 1); Solid Rocket Boosters (volume 3); Space Shuttle (volume 3); Teacher in Space Program (volume 3); Women in Space (volume 3).
Jenkins, Dennis. Space Shuttle: The History of Developing the National Space Transportation System. Indian Harbour Beach, FL: Jenkins, 1996.
Vaughan, Diane. The Challenger Launch Decision. Chicago: University of Chicago Press, 1996.
NASA Kennedy Space Center. "51-L Shuttle Mission." <http://www-pao.ksc.nasa.gov/kscpao/shuttle/missions/51-l/mission-51-l.html>.
Wade, Mark. "STS-51-L." <http://www.astronautix.com/details/sts51l.htm>.
"Challenger." Space Sciences. . Encyclopedia.com. (September 11, 2018). http://www.encyclopedia.com/science/news-wires-white-papers-and-books/challenger
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Challenger, U.S. space shuttle. It exploded (Jan. 28, 1986) 73 seconds into its tenth flight, killing all seven crew members, including the first civilian in space, schoolteacher Christa McAuliffe. The disaster was caused by the faulty design of a gasket (the O-ring seal). As dramatically demonstrated by Richard Feynman, a member of the presidential commission appointed to investigate the accident, the elastic O-ring did not respond as expected because of the cold temperature (30°F/-1°C) at launch time. (At a news conference, Feynman illustrated the loss of elasticity by dropping an O-ring into a glass of cold water.) As a result of the explosion, the United States did not send astronauts into space for almost three years as the National Aeronautics and Space Administration redesigned a number of features of the space shuttle.
"Challenger." The Columbia Encyclopedia, 6th ed.. . Encyclopedia.com. (September 11, 2018). http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/challenger
"Challenger." The Columbia Encyclopedia, 6th ed.. . Retrieved September 11, 2018 from Encyclopedia.com: http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/challenger
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"challenger." Oxford Dictionary of Rhymes. . Encyclopedia.com. (September 11, 2018). http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/challenger
"challenger." Oxford Dictionary of Rhymes. . Retrieved September 11, 2018 from Encyclopedia.com: http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/challenger
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George H. W. Bush
Remarks Announcing the Winner of the Teacher in Space Project
Presented on July 19, 1985
Address to the Nation on the Explosion of the Space Shuttle
Presented on January 28, 1986
The midair explosion of the space shuttle Challenger on January 28, 1986, marked the first major in-flight disaster in the history of the U.S. space program. Seven passengers—the entire crew—lost their lives. Mourned by the nation, the loss of the crew and the shuttle resulted in an official investigation that called for far-ranging reforms in the National Aeronautics and Space Administration (NASA).
The seven-member crew of the space shuttle Challenger—Francis R. Scobee (1939–1986), Michael J. Smith (1945–1986), Ellison S. Onizuka (1946–1986), Ronald McNair (1946–1986), Judith A. Resnick (1949–1986), Gregory Jarvis (1944–1986), and Christa McAuliffe (1948–1986)—were used to national attention prior to the horrific tragedy of January 28. Christa McAuliffe was not a trained pilot or a scientist. She was a social studies teacher in Concord, New Hampshire, who had been selected from among eleven thousand applicants to be the first private citizen sent into space.
After an exhaustive search, McAuliffe was informed by Vice President George H. W. Bush (1924–) that she would be the first "Teacher in Space." The vice president spoke to the ten project finalists at 1:18 p.m. in the Roosevelt Room at the White House. He was introduced by James M. Beggs (1926–), Administrator of NASA. The winner and backup teacher were presented with small statues on behalf of NASA and the Council of Chief State School Officers. President Ronald Reagan (1911–2004), who was in Bethesda Naval Hospital recovering from surgery, was unable to attend the event.
Things to remember while reading Vice President Bush's Remarks Announcing the Winner of the Teacher in Space Project:
- McAuliffe was selected from over eleven thousand applicants and was not trained as an astronaut. Her selection was viewed by many as a sign that space travel was possible for the average person.
- Vice President Bush says that NASA searched the nation to find a teacher with "the right stuff" to make the Challenger flight. He is referring to The Right Stuff, a book by Tom Wolfe (1931–; see entry) about the Mercury 7, the first seven American men chosen to travel into space. These astronauts were national heroes.
Vice President Bush's Remarks Announcing the Winner of the Teacher in Space Project
The Vice President. We're here today to announce the first private citizen passenger in the history of space flight. The President [RonaldReagan] said last August that this passenger would be one of America's finest—a teacher. Well, since then, as we've heard, NASA, with the help of the heads of our State school systems, has searched the Nation for a teacher with "the right stuff." Really, there are thousands, thousands of teachers with the right stuff. And they're committed to quality in education; to teaching their students the basics—reading, writing, mathematics, science, literature, history—to teaching the foundations of our cultural heritage; to teaching the values that guide us as Americans; and to teaching that important, but difficult to obtain, quality—clarity of thought.
We're honoring all those teachers of merit today, and we're doing something else because the finalists here with me and the more than a hundred semifinalists will all in the months ahead serve, as Jim has said, as a link between NASA and the Nation's school system. These teachers have all received special NASA training to pass on to other teachers and to their students. And together they and NASA will be a part of an exciting partnership for quality in education.
So, let me tell you now who our teacher in space will be. And let me say I thought I was a world traveler, but this tops anything I've tried. And first, the backup teacher, who will make the flight if the winner can't: Barbara Morgan of the McCall-Donnelly Elementary School in McCall, Idaho. Barbara has been a teacher for eleven years. She first taught on the Flathead Indian Reservation in Montana. She currently teaches second grade. Congratulations. And we have a little thing for you [a small statue].
And the winner, the teacher who will be going into space: Christa McAuliffe. Where is—is that you? [Laughter] Christa teaches in Concord High School in Concord, New Hampshire. She teaches high school social studies. She's been teaching for twelve years. She plans to keep a journal of her experiences in space. She said that—and here's the quote—"Just as the pioneer travelers of the Conestoga wagon days kept personal journies [journals], I as a space traveler would do the same." Well, I'm personally looking forward to reading that journal some day.
And by the way, Christa, while you're in the program, Concord High obviously will need substitute teachers to fill in. And it's only right that we provide one of these substitutes. So, the first class you miss, your substitute will be my dear friend and the President's, Bill Bennett (1943–), the Secretary of Education.
So, congratulations to all of you. Good luck, Christa, and God bless all of you. Thank you very much for coming. And you, too, get one of these [small statues].
Ms. McAuliffe: It's not often that a teacher is at a loss for words. I know my students wouldn't think so. I've made nine wonderful friends over the last two weeks. And when that shuttle goes, there might be one body, but there's going to be ten souls that I'm taking with me.
The Challenger explosion
McAuliffe's joining the Challenger crew was not the only headline-grabbing detail. NASA had announced in early January 1986 that it planned to conduct fifteen missions in twelve months, using all four of its shuttles—Columbia, Challenger, Atlantis, and Discovery. Immediately there were problems. The first mission was postponed seven times before the first shuttle was launched on January 12. Because of severe weather, the spacecraft was forced to return to Earth late, setting NASA further behind in its ambitious schedule. Feverish work began on preparing the Challenger for its mission. The spacecraft had just returned from its ninth flight only two months earlier but was scheduled to return to space on January 22. The mission was considered a high priority because of the massive press attention McAuliffe had been receiving. Schoolchildren around the world were expecting live reports from space to be given by McAuliffe. As part of the mission, NASA was launching a tracking and data relay satellite (TDRS) and the high-priority Spartan-Halley comet research observatory into space. The flight was scheduled to last six days, during which time the Spartan observatory would be recovered from orbit. Because of tight schedule requirements, the Spartan could be orbited no later than January 31.
The January 22 launch date arrived but the mission was delayed. Two more delays—on January 24 and January 25—followed. Bad weather prevented a launch on January 26, pushing the mission back to the next day, Monday, January 27. After a problem with the hatch bolt was detected, the mission was once again postponed. During the night of January 27, the temperature at Cape Canaveral dropped as low as 19°F (-7.2°C). This prompted a late-night meeting of NASA managers and engineers with managers from Morton Thiokol, the government contractor that manufactured the O-rings on the booster rockets. (A booster rocket is fired to propel the spacecraft into space. The booster rocket is built in sections and then strapped onto the shuttle. The rubber O-rings are required to seal the sections together.) The Thiokol engineers were concerned that the O-rings would stiffen in the cold and cause the seal to fail. Since the O-rings had never been tested at low temperatures, the Thiokol managers overruled the engineers. They signed a statement claiming that the boosters were safe for launch at a temperature lower than 53°F (11.7°C).
Other problems arose on the morning of January 28 because a thin layer of ice had formed on the shuttle and the
launchpad. Liftoff was delayed twice because officials at the site were concerned about icicles potentially breaking off during launch and damaging insulation tiles that protected the shuttle from intense heat as it reentered Earth's atmosphere. Inspection teams examined the Challenger and reported no abnormalities. Countdown proceeded, and at 11:38 a.m. the Challenger lifted off into the blue sky. After two explosions—the first at fifty-four seconds into the launch and the second at seventy-three seconds—the space shuttle disintegrated, vanishing in a trail of smoke as a crowd on the ground and millions of television viewers throughout the world watched in disbelief. Among the spectators on the ground were McAuliffe's husband and two children and a group of her students.
President Reagan's State of the Union Address (an annual speech delivered by a U.S. president) had been scheduled for the evening of January 28. Reagan abandoned his original text, choosing instead to pay tribute to the Challenger crew.
Things to remember while reading President Reagan's Address to the Nation on the Explosion of the Space Shuttle Challenger:
- With the exception of Apollo 1, in which three astronauts were killed in 1967 in a ground accident, no American astronaut had lost his or her life during an in-flight mission prior to the Challenger explosion.
- For those who witnessed the live television broadcast of the Challenger explosion, the event was dramatic and shocking. Today, most people remember exactly where they were when the tragedy occurred.
President Reagan's Address to the Nation on the Explosion of the Space Shuttle Challenger
Ladies and gentlemen, I'd planned to speak to you tonight to report on the state of the Union, but the events of earlier today have led me to change those plans. Today is a day for mourning and remembering. Nancy [First Lady Nancy Reagan; 1923–] and I are pained to the core by the tragedy of the shuttle Challenger. We know we share this pain with all of the people of our country. This is truly a national loss.
Nineteen years ago, almost to the day, we lost three astronauts in a terrible accident on the ground. But we've never lost an astronaut in flight; we've never had a tragedy like this. And perhaps we've forgotten the courage it took for the crew of the shuttle. But they, the Challenger Seven, were aware of the dangers, but overcame them and did their jobs brilliantly. We mourn seven heroes: Michael Smith, Dick Scobee, Judith Resnick, Ronald McNair, Ellison Onizuka, Gregory Jarvis, and Christa McAuliffe. We mourn their loss as a nation together.
For the families of the seven, we cannot bear, as you do, the full impact of this tragedy. But we feel the loss, and we're thinking about you so very much. Your loved ones were daring and brave, and they had that special grace, that special spirit that says, "Give me a challenge, and I'll meet it with joy." They had a hunger to explore theuniverse and discover its truths. They wished to serve, and they did. They served all of us. We've grown used to wonders in this century. It's hard to dazzle us. But for twenty-five years the United States space program has been doing just that. We've grown used to the idea of space, and perhaps we forget that we've only just begun. We're still pioneers. They, the members of the Challenger crew, were pioneers.
And I want to say something to the schoolchildren of America who were watching the live coverage of the shuttle's takeoff. I know it is hard to understand, but sometimes painful things like this happen. It's all part of the process of exploration and discovery. It's all part of taking a chance and expanding man's horizons. The future doesn't belong to the fainthearted; it belongs to the brave. The Challenger crew was pulling us into the future, and we'll continue to follow them.
I've always had great faith in and respect for our space program, and what happened today does nothing to diminish it. We don't hide our space program. We don't keep secrets and cover things up. We do it all up front and in public. That's the way freedom is, and we wouldn't change it for a minute. We'll continue our quest in space. There will be more shuttle flights and more shuttle crews and, yes, more volunteers, more civilians, more teachers in space. Nothing ends here; our hopes and our journeys continue. I want to add that I wish I could talk to every man and woman who works for NASA or who worked on this mission and tell them: "Your dedication and professionalism have moved and impressed us for decades. And we know of your anguish. We share it."
There's a coincidence today. On this day 390 years ago, the great [British] explorer Sir Francis Drake [c. 1540–1596] died aboard ship off the coast of Panama. In his lifetime the great frontiers were the oceans, and an historian later said, "He lived by the sea, died on it,and was buried in it." Well, today we can say of the Challenger crew: Their dedication was, like Drake's, complete.
The crew of the space shuttle Challenger honored us by the manner in which they lived their lives. We will never forget them, nor the last time we saw them, this morning, as they prepared for their journey and waved goodbye and "slipped thesurly bonds of earth" to "touch the face of God."[Quoted from American pilot John Gillespie Magee Jr.'s poem, "High Flight."]
What happened next …
A few days after the disaster, President Reagan eulogized (praised in a formal statement) the Challenger crew during a television memorial ceremony at the Johnson Space Center in Houston, Texas. On February 3, 1986, he established a presidential commission to investigate the accident, appointing former Secretary of State William P. Rogers (1913–2001) as head. Six weeks after the tragedy the shuttle's crew module was recovered from the floor of the Atlantic Ocean. The crew members were subsequently buried with full honors. There was considerable speculation about whether they had survived the initial explosion. Evidence gathered later by NASA indicated that they had survived the breakup and separation of the boosters from the shuttle. They had also begun to take emergency action inside the crew cabin. Whether all seven remained conscious through the two-minute, forty-five second fall into the ocean remains unknown. NASA investigators determined that at least two were breathing from emergency air packs they had activated.
On June 6, 1986, the Rogers Commission released a 256-page report stating that the explosion was caused by destruction of the O-rings. After checking into the history and performance of the sealing system, the commission discovered that the O-rings had failed regularly, though only partially, on previous shuttle flights. Both NASA and Thiokol were concerned about weaknesses in the seals, but they had chosen not to undertake a time-consuming redesign of the system. They regarded O-ring erosion as an "acceptable risk" because the seal had never failed completely. But when the Challenger flew in the dead of winter, frigid temperatures made the O-rings so brittle that they never sealed the joint. Even before the shuttle had cleared the launch tower, hot gas was already seeping through the rings. Investigators blamed NASA and Thiokol management procedures for not allowing critical information to reach the right people. The U.S. House of Representatives Committee on Science and Technology then conducted hearings on the matter. The committee determined that NASA and Thiokol had sufficient time to correct the O-ring problem, but the space agency and the manufacturer had sacrificed safety to meet flight schedules and cut costs.
The charges had a grave impact on NASA. Public confidence was shaken, and the astronaut corps was highly concerned. Astronauts had never been consulted or informed about the dangers posed by the O-ring sealing system. The Rogers Commission made nine recommendations to NASA, among them allowing astronauts and engineers a greater role in approving launches. The other recommendations included a complete redesign of the rocket booster joints, a review of astronaut escape systems, regulation of scheduling shuttle flights to assure safety, and sweeping reform of the shuttle program and management structure.
Following these decisions, several top officials left NASA. A number of experienced astronauts also resigned as a result of disillusionment with NASA and frustration over the long redesign process that delayed their chances to fly in space. An American shuttle was not launched again until September 29, 1988. NASA eventually built the Endeavour to replace the Challenger, and it flew for the first time in 1992.
Did you know …
- The Apollo rockets were replaced by the space shuttle designs. The last rocket, Apollo 17, flew in December 1972.
- The "Teacher in Space" program was discontinued after the Challenger explosion.
- The space shuttle Columbia (see Columbia Space Shuttle Disaster entry) broke apart over the western United States on February 1, 2003, killing all seven crew members. It was the first major space disaster since the Challenger explosion.
Consider the following …
- Private citizens have approached NASA and offered millions of dollars to accompany a trained crew on a shuttle mission. So far NASA has declined these offers. Do you think private citizens should be allowed to fly on shuttle missions? Why or why not?
- Some people want to start private companies that will fly people into space. On June 23, 2004, American test pilot Mike Melvill (1941–) successfully flew the rocket plane SpaceShipOne 62.5 miles (100 kilometers) over the Mojave Desert in California. Many members of NASA are opposed to this, saying that space travel is still highly complicated and should be left to the professionals. Do you think space travel should be limited to NASA—a government agency—or do you think private citizens, if properly trained and equipped, should be allowed to travel into space without NASA's involvement? Why or why not?
For More Information
McConnell, Malcolm. Challenger: A Major Malfunction. New York: Doubleday, 1987.
"Looking for What Went Wrong." Time (February 10, 1986): pp. 36–38.
"NASA Faces Wide Probe." U.S. News and World Report (February 17, 1986): pp. 18–19.
"Out of Challenger's Ashes—Full Speed Ahead," U.S. News and World Report (February 10, 1986): pp. 16–19.
"Seven Who Flew for All of Us." Time (February 10, 1986): pp. 32–35.
"What Happened?" Newsweek (February 17, 1986): pp. 32–33.
Bush, George H. W. Remarks Announcing the Winner of the Teacher in Space Project, July 19, 1985. Ronald Reagan Presidential Library, University of Texas.http://www.reagan.utexas.edu/resource/speeches/1985/71985a.htm (accessed on July 19, 2004).
"Columbia." NASA.http://www.nasa.gov/columbia/home/index.html (accessed on July 19, 2004).
"Information on the STS–51L/Challenger Accident." NASA.http://www.hq.nasa.gov/office/pao/History/sts51l.html (accessed on July 19, 2004).
January 28, 1986: The Challenger Disaster.http://www.chron.com/content/interactive/special/challenger (accessed on July 19, 2004).
Reagan, Ronald. Address to the Nation on the Explosion of the Space Shuttle Challenger, January 28, 1986. Ronald Reagan Presidential Library, University of Texas.http://www.reagan.utexas.edu/resources/speeches/1986/1288b.htm (accessed on May 15, 2004).
Surly: Arrogant, domineering.
"Challenger." Space Exploration Reference Library. . Encyclopedia.com. (September 11, 2018). http://www.encyclopedia.com/science/encyclopedias-almanacs-transcripts-and-maps/challenger
"Challenger." Space Exploration Reference Library. . Retrieved September 11, 2018 from Encyclopedia.com: http://www.encyclopedia.com/science/encyclopedias-almanacs-transcripts-and-maps/challenger