One Moment That Made the World Stand Still: The Challenger Disaster
One Moment That Made the World Stand Still: Challenger
On January 28, 1986, as the United States and the rest of the world watched on, glued to television sets for the live broadcast of an unprecedented space shuttle launch, there was excitement and expectation in the air. This was a launch that had been delayed multiple times, but now - finally - it was all systems go, and all eyes on the crisp, blue Florida sky.
And yet, all of the good feeling would only ever amount to a desperate, devastating, infamous tragedy. The Challenger Disaster triggered global shock and mourning. All seven crew members lost their lives amidst one of the darkest moments in twentieth century American history. But, how could such a moment come to pass? What exactly went so terribly wrong to cause such a deadly outcome? And how did the fate of Challenger impact space travel from then on?
This is WatchMojo. Today we examine Space Shuttle Challenger’s final mission, the disturbing events leading up to, during, and after its catastrophic launch, and the enduring impact of an unthinkable failure.
Challenger was the second Space Shuttle Orbiter (after Columbia) to fly as part of NASA’s wider Space Shuttle Program - a huge, $200 billion dollar, thirty-year human spaceflight plan, that ultimately ran from 1981 until 2011. Challenger itself launched for the first time on April 4th, 1983. It ran for ten flights, total, between then and mission number STS-51-L - its fatal, final launch in late January 1986.
In general, the Shuttle Program represented a new dawn for spaceflight. Unlike with previous initiatives - such as the Apollo Program, which famously took humankind to the moon for the first time - NASA’s shuttle system was designed for repeated use. The crewed vehicles were reusable, and by some estimates it was predicted that any one shuttle would be able to launch upwards of 100 times over the course of its operational life. Unfortunately, we know that Challenger managed only a tenth of that projection. What transpired to be its final mission, however, was planned to be a particularly historic one. It carried enormous symbolic weight, cultural significance, and it garnered massive political attention.
At its core, STS-51-L was to carry out several key tasks. Challenger was set to deploy the second satellite in NASA’s Tracking and Data Relay Satellite System, which was designed to make it easier for orbiting spacecraft, in general, to communicate. It was also planned for Challenger to ferry into space the Spartan Halley payload, a satellite specifically built to target and monitor Halley’s Comet. And, in fact, this link to an internationally known cosmic phenomenon was a main driving force behind this particular mission being a focal point for a key NASA initiative during the then-presidency of Ronald Regan - the Teacher in Space Project.
When, in 1984, Reagan announced the Teach in Space Project, the idea was a bold one: send a teacher into space so that students across the US could witness the possibilities of space travel through the eyes of someone just like them. In 1985, from more than 11,000 applicants, Christa McAuliffe, a social studies teacher from Concord, New Hampshire, was chosen. She wasn’t an astronaut, a pilot, or an engineer - she was an educator. And she represented the possibility that space wasn’t only for highly trained specialists; that it could also be for everyday people. Alongside McAuliffe, another teacher, Barbara Morgan, was selected as her backup.
McAuliffe was scheduled to teach directly from space. The plan was for her to deliver two 15-minute classes, broadcast live to millions of students around the country. For NASA, this was a sign of ambition, but also a thinly-veiled, major push to improve PR. The 1980s had seen a big decline in enthusiasm for space travel compared to previous decades, especially during the Apollo era. Challenger was meant to reignite the flame; to re-accelerate public interest in US plans for (and spending on) space. It was an attempt to inspire the next generation of America’s children. And, in the year leading up to launch, with media attention rising and rising, McAuliffe was right at the heart of it all.
Of course, she wasn’t alone. The full crew of STS-51-L included Francis R. “Dick” Scobee, the mission commander; Michael J. Smith, the pilot; Mission Specialist 1, Ellison S. Onizuka; Mission Specialist 2 and Flight Engineer, Judith A. Resnik; Mission Specialist 3, Ronald E. McNair; and Payload Specialist 2, Gregory B. Jarvis, an engineer representing Hughes Space and Communications. Christa McAuliffe was officially designated as Payload Specialist 1. At the time, it was one of the most diverse crews that NASA had ever assembled. Again, this was a group of supremely talented and dedicated people who, it was felt, could supercharge the Shuttle Program.
Because, in truth, by the turn of the year into 1986, the program was increasingly under pressure. NASA had promised routine, almost airline-like operations for the shuttle. Launches were originally expected to happen at a rapid pace, with perhaps dozens per year. But, just five years into the shuttle era, this general ambition had proven, in hindsight, to be over-optimistic. As a result, NASA’s leadership reportedly faced growing demands to prove their shuttles were not just experimental crafts but truly were reliable, reusable, around-the-clock vehicles.
Nevertheless, the STS-51-L Challenger mission had already faced delays. Originally scheduled to launch in July, 1985, it had been pushed back multiple times due to a combination of weather and technical issues. Even in January ‘86, it had previously been scheduled for launch on the 22nd, before eventually taking off on the 28th.
That morning, the country was ready. Millions of people, including schoolchildren across America, tuned in live to watch. The Challenger mission was supposed to be a celebration of progress, education, imagination and exploration. Instead, it turned into a moment that no-one would forget, but for terrible, horrible reasons. Just 73 seconds after leaving the launchpad there was a huge explosion. The watching crowds had just witnessed a dream disintegrate.
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Challenger’s final day did not unfold under stereotypical Florida conditions. While skies were clear, temperatures were plummeting. Overnight lows had dipped below freezing, and something that may have been missed by the eager, watching masses was that this launch would be the coldest launch in shuttle history. Ultimately, this was a critical detail as to how (and why) the mission ended in disaster.
The cold wasn’t just uncomfortable, it was dangerous. Ice had formed on the ground and on the launch tower, against which the doomed shuttle was set - raising concerns among engineers. Broadly, the Shuttle Program simply wasn’t designed with such extreme cold in mind. And one component to the launch in particular, the O-rings - which are rubber seals inside the solid rocket boosters - were thought to be especially vulnerable.
The two rocket boosters can be seen flanking the shuttle at launch. It’s these that should’ve provided the majority of the thrust needed for Challenger to get off the ground, and escape Earth’s atmosphere. Working correctly, they should have facilitated a huge amount of burning fuel before detaching from the vehicle, at which stage the main engines take over. Significantly, though, the rocket boosters were built in multiple parts, and then assembled on-site in Florida, with the crucial O-rings used to seal the joins.
On the night before Challenger’s final launch, engineers at Morton Thiokol, the company that manufactured the boosters, had reportedly voiced strong objections - specifically relating to the O-rings. There had been multiple prior instances (in testing and previous flights) dating back to the 1970s, to seemingly show evidence of O-ring erosion in cold weather. The concern, in general, was that the cold caused the O-rings to stiffen, to lose flexibility, which in turn meant that they couldn’t seal as they were supposed to. In a now infamous teleconference - held between senior figures at NASA and Morton Thiokol on January 27th, mere hours before launch - several Thiokol engineers are said to have warned NASA managers directly that the O-rings could fail in low temperatures. Their initial recommendation was to postpone the launch again, until the weather warmed up.
But NASA, under enormous pressure to keep to schedule, reportedly pushed back. In the years since, it’s alleged that the higher-ups feared the optics of another delay - especially with the Teacher in Space Project commanding so much public attention. After tense debate on that same teleconference call, some key Thiokol representatives reversed their engineers’ recommendation and gave the go-ahead. The stage was set. The tragedy was imminent.
By dawn, the launch site was a buzz. The families of crew members had gathered to watch first hand, at the Kennedy Space Center. Schools stopped lessons nationwide, as classes gathered together to tune in. For many, this was the first time they’d ever watched a live space launch. The crew boarded, memorably smiling and waving for the cameras until the very last moment. Outside, the ice on the launch pad remained a concern. Workers tried to hurriedly melt what remained, while the air was still biting cold. The countdown continued nonetheless.
At 11:38 a.m. Eastern Standard Time, Challenger’s main engines roared into life. Air temperature at the time was 36 degrees Fahrenheit, 2 degrees Celsius. The boosters ignited. The shuttle lifted off the pad, the vehicle soared into the sky, and cheers erupted from the watching crowd. To the untrained eye it might’ve all been going as planned. But, actually, even during the earliest stages there were immediate signs that something was wrong. Nine short, sharp clouds of black-gray smoke spurted out from the right-hand booster within just the first few seconds of the launch sequence. Subsequent investigations found that these clouds were the first visible warning that the O-rings had indeed failed; that the joints inside the boosters had not sealed; that there were leaks in the system; and that, ultimately, the crew was doomed.
Still, for the first minute, everything appeared normal, with Challenger seemingly accelerating smoothly. All the while, though, pressure was building, and fuel was flooding where it shouldn’t have been. Fifty-eight seconds into the flight, a noticeable (and abnormal) plume began erupting from the right booster. Fifty-nine seconds in, the shuttle hit max Q, the point of maximum aerodynamic pressure. At sixty-eight seconds, mission control radioed, “Challenger, go at throttle up,” and Commander Scobee confirmed, “Roger, go at throttle up” - his last recorded words. At seventy-two seconds, a massive structural failure began. An instantaneous and catastrophic chain reaction and, at seventy-three seconds after launch, Challenger fully broke apart in a violent fireball.
To viewers on the ground and to those watching on TV, the sudden orange and white bloom was difficult to comprehend at first. Confusion reigned as the newly-twisting contrails split and raced in different and unpredictable directions. Some may have momentarily clung to a hope that what they were seeing was still all part of the plan. But it wasn’t. And, as the realisation dawned, as it became clear that something was wrong, a distraught sense of disbelief and horror passed all over the US.
Stunned silence on the ground, punctuated by the gasps and cries of friends and family members. In schools all over, teachers scrambled to turn off TVs, unsure what to say to their students. At mission control, confirmation quickly filtered through. “Flight controllers here are looking very carefully at the situation,” said the NASA Public Affairs Officer Steve Nesbitt before, moments later, “We have a report from the Flight Dynamics Officer that the vehicle has exploded”.
This mission, purposefully designed to get people excited about space travel again, had just shattered across the sky. All seven of the crew members had just then lost their lives in the name of science and exploration. The nation had just witnessed the deadliest accident in American spaceflight history.
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In the weeks, months and years after the Challenger Disaster, more and more details emerged. Disturbingly, the exact fate of Challenger’s seven individual astronauts - during those final moments - remains somewhat unclear. However, we know that some (or even all) may not have died during the initial explosion.
Later investigations revealed that the crew cabin had survived the initial breakup relatively intact. The cabin continued upward for nearly 25 seconds - reaching a peak distance above sea level of 65,000 feet - before beginning its deadly descent. At around two minutes and forty-five seconds after the mid-air explosion had torn the vehicle apart, the cabin hit the ocean. At that stage it was travelling at over 200 miles per hour. The impact was a force too great for anyone to survive.
Evidence suggests, though, that the crew may have remained conscious for at least part of the fall. Emergency air packs were activated for three of the seven astronauts. Multiple electrical switches were found to have been toggled on and off. While the crash into the ocean was responsible for the majority of the final wreckage, there were signs of a last ditch struggle to regain control of the cabin by at least some on board. These details in particular led to debate around the potential (or lack thereof) for crew members to escape. Challenger was not fitted with an escape system. One had been considered during development of the shuttle, but was ultimately passed on thanks to a combination of cost, weight, and a seeming lack of necessity - due to the perceived reliability of the shuttle itself. The decision not to fit with an escape system became one of many that would be heavily scrutinized afterwards.
NASA’s first priority in the immediate aftermath of the disaster, however, was to recover debris and investigate the cause. Rescue teams from the US Navy and Air Force were dispatched to locate parts of the shuttle over hundreds of square miles of ocean. It was a long recovery process, involving surface operations for more than a week, and submarine operations for months thereafter. In March, the first confirmed evidence of the failed O-ring seal in the right booster was found. In April, the crew cabin was located, with the remains of all seven crew members inside.
On the evening of the disaster, President Reagan spoke to the nation from the Oval Office. He had been due to deliver the 1986 State of the Union Address on that day, at that time, during which he had reportedly, originally planned to mention the success of Challenger earlier that morning. But, in light of the tragedy, the State of the Union was postponed. Reagan instead spoke for four minutes, first to offer condolences and to reflect on America’s anguish, and then to praise the courage of the Challenger crew. His speech sought to unite a grieving nation, while it also served to promise that this wouldn’t be the end of American space travel.
That said, the repercussions spread far and wide. On February 6th 1986, a week after Challenger’s final launch, Reagan set up the Presidential Commission on the Space Shuttle Challenger Accident - which became known as the Rogers Commission, after its chairman (and former Secretary of State) William P. Rogers. The panel was made up of astronauts, engineers, and scientists - including (among others) Neil Armstrong, the first person to walk on the Moon; Sally Ride, America’s first female astronaut; and Richard Feynman, the famed physicist.
The Rogers Commission had a singular task: to determine the cause of the accident and make recommendations to prevent it from happening again. Those involved conducted an exhaustive investigation, interviewing NASA and contractor personnel, reviewing technical documents, and examining recovered shuttle debris. The commission’s work was methodical, intense, and politically sensitive.
The technical cause of the disaster was quickly confirmed: a failure of the O-rings in the right solid rocket booster. It was an expected verdict for many who were involved with the launch, given again that some had raised concerns about precisely this issue on the evening beforehand. These rubber seals were six meters across, and they should have prevented hot gases escaping between the joints of the booster. But the cold weather had caused them to harden and lose elasticity. The effect was memorably demonstrated during a televised hearing by Richard Feynman, who submerged a small sample of the O-ring material in ice water to show how stiff and unreliable it became. Ultimately, the O-rings were a vital component but they became brittle. And when one in the right booster broke under the pressure of lift off, it set off the deadly chain of events that followed.
More damningly, the Rogers Commission found that NASA and its contractors had underestimated the risk of launching in low temperatures and had not adequately addressed those repeated warnings from the engineers. As it was also determined that NASA had known about the flawed O-ring design since at least 1977, what happened to Challenger was notably described by the commission as being “an accident rooted in history”.
Investigators concluded that management decisions had prioritized the Agency’s ambitious schedule over safety concerns. In pursuit of increasing the number of space shuttle flights departing Earth, NASA had overlooked important technical issues, the likes of which eventually contributed to the Challenger Disaster. It was found that general communication was lacking between NASA’s technical engineers and the decision-makers at the top. Feynman, in particular, highlighted how some of the higher managers were missing even an adequate understanding of the technical aspects to spaceflight. Meanwhile, NASA’s risk assessment policies were also found to be seriously lacking and dangerously ineffective.
In its final report, the Rogers Commission issued recommendations for NASA under nine chapters - covering everything from “Criticality Review and Hazard Analysis” to “Landing Safety”, “Flight Rate” and “Maintenance Safeguards”. In the wake of Challenger, NASA was forced to massively redesign its model. What had for so long stood as a symbol of American pride and ambition, was now one steeped in shock and controversy. Despite all the intentions of this specific flight, NASA’s PR had never been worse.
The space shuttle program was grounded for two years and eight months while investigations continued and changes were made. A new department - the Office of Safety, Reliability, and Quality Assurance - was created. An escape option was added to the shuttle design, although even it wouldn’t have specifically saved the Challenger crew. The rocket boosters were redesigned to include safety features to prevent an O-ring failure.
In August 1986, approval came from President Reagan to build Space Shuttle Endeavour, Challenger’s replacement in the fleet. In September 1988, Space Shuttle Discovery successfully launched for mission number STS-26, heralded by NASA as its “Return to Flight”. The Teacher in Space program was cancelled in 1990, but reintroduced in ‘98 as the Educator Astronaut Project. Barbara Morgan - Christa McAuliffe’s backup - did eventually fly as part of that project, on Endeavour, for mission number STS-118, in 2007.
But for some, while there were changes made, they never truly went far enough. Following the Columbia Disaster in 2003, the Columbia Accident Investigation Board found that “the causes of the institutional failure responsible for Challenger have not been fixed,” concluding that similar organizational issues had contributed to Columbia’s deadly failed reentry. The technical cause for Columbia was wholly different to Challenger, but the backdrop - the communication, decision-making and culture within NASA - was again found to be at fault.
Challenger’s destruction was an American tragedy, but one that reverberated all over the world. In countries with their own space programs, it became a cautionary tale about the dangers of overconfidence and bureaucratic pressure. For everyone watching on, it showed that human spaceflight, no matter how advanced, carries with it huge inherent risks.
During his speech from the Oval Office, on the day of the disaster, President Reagan reflected that “we’ve grown used to the idea of space, and perhaps we forget that we’ve only just begun”. At the time, and still today, the terrible fate of Challenger proves that the complexity of space missions (and the courage needed from those who undertake them) should always be remembered.
