What caused the catastrophic failure of the Space Shuttle Challenger on that cold Florida morning of January 28, 1986? From a technical perspective, experts cite lower-than-expected launch temperatures at Florida's Cape Canaveral, which caused a tiny rubber part called an O-ring to malfunction. But as a broader investigation by the specially appointed Rogers Commission would reveal, the tragedy could have been avoided had there not been significant error of judgement on the part of decision makers at NASA.
Challenger Needed to Rekindle America's Romance With Space
By January of 1986 America was already bored with spaceflight.
It was, in part, NASA’s own fault. The government agency had debuted the space shuttle program five years earlier with an aggressive public-relations message that the reusable vehicles would make access to space both affordable and routine. Projected frequency: more than 50 flights a year.
But had space flight become…too routine? Even as the shuttle undertook fewer than one-tenth that many flights, excitement quickly waned. Television coverage slacked. Missions—to conduct research, repair satellites, and build the International Space Station—failed to ignite popular imaginations the way a moon landing had. For many Americans, shuttle flights carried little of the bravado and romance of the Apollo era.
The launch on January 28, 1986, was different. The sun had been up for less than an hour and air temperatures were a few notches above freezing when the crew of STS-51L boarded the orbiter Challenger that Tuesday morning.
All around the country people were getting excited—in large part because the seven-person crew’s included Payload Specialist Christa McAuliffe, a schoolteacher and mother of two chosen to fly as part of NASA’s Teacher in Space program. As a civilian, she was PR catnip: infinitely relatable and proof that space was now truly open to average Americans, not just hot-shot fighter jocks. Kids nationwide would watch the launch live and know that no dream was beyond reach.
The 'Space for Everyone' Dream Shattered That Morning
But 73 seconds after Challenger’s launch, that dream quickly became a nightmare. Challenger disappeared as white vapor bloomed from the external tank. Spectators were stunned. Teachers scrambled to get their kids out to recess. And images of the grotesque, Y-shaped explosion dominated the news cycle for days to come. For the first time in its history, NASA had lost a crew on a mission—with the nation watching.
More than three decades later, the image of that explosion remains as iconic as Buzz Aldrin standing on the moon. Challenger not only taught America a lesson about faulty O-rings and hubris; it forever changed our relationship with spaceflight and our tax-funded space agency.
We’re now in a new era where private companies, eyeing Mars, are starting to shift the spaceflight spotlight away from government efforts. Will these billionaire dreamers avoid the mistakes of the past? Whoever participates in the next space wave can learn a lot from Challenger’s ill-fated flight.
Cold Temperatures Caused a Tiny O-Ring to Malfunction
In the months that followed the accident, a Presidential Commission led by former Secretary of State William P. Rogers—the so-called Rogers Commission—went through every piece of data to identify the disaster’s root cause. What they found was a very different launch than the one people had watched on TV.
Pictures of the shuttle on the launch pad showed a puff of black smoke issuing from the bottom of the right solid rocket booster. Video of the shuttle’s flight showed that the smoke disappeared, only to be replaced by a flame 66 seconds after launch. That flame grew alarmingly rapidly and was forced towards the big orange fuel tank by the slipstream as the shuttle rose ever higher.
Data on the ground confirmed it was a leak in the booster, but no one could do anything about it. The solid rocket boosters couldn’t be shut down, and there was no abort option while they were firing. That flame eventually burned through the shuttle’s external tank, rupturing the liquid-hydrogen tank milliseconds before the right booster crashed into the liquid-oxygen tank. The two liquids mixed and exploded, destroying the orbiter with it.
The source of the leak, as America soon learned, was traced to a tiny rubber part called an O-ring, which formed the seal between sections of the solid rocket boosters. It was just one of many known “potentially catastrophic” elements of the space shuttle, sensitive to a number of factors—including extreme cold. If exposed to near-freezing temperatures, the O-ring lost its elasticity. Famed theoretical physicist Dr. Richard Feynman demonstrated what this meant at a press conference five months later. He twisted a small O-ring in a vice, then dipped it in a glass of ice water. When he pulled it out, it kept its twisted shape, showing its lack of resilience to cold. In Challenger’s case, the O-ring got so cold it hadn’t expanded properly and allowed the leak.
This raised a more pressing question. The O-ring was known to be sensitive to cold and could only work properly above 53 degrees. Temperature on the launch pad that morning was 36 degrees. Why did NASA launch at all?
Info Relayed to Decision Makers Was Incomplete and Misleading
To find an answer, the Rogers Commission interviewed engineers and decision-makers at both NASA and Morton Thiokol, the company that built the solid rocket boosters. What it found was a stunning lack of communication—almost as if officials had been playing a game of broken telephone, with the result that incomplete and misleading information reached NASA’s top echelons. And among that ill-translated information were concerns about the O-rings. The issue was completely absent from all the flight-readiness documents.
That wasn’t the end of it. During a teleconference some 12 hours before launch, Thiokol engineers told NASA management about their concerns over the O-rings. Overnight temperatures were set to drop to 20 degrees, which raised an additional ice concerns. An early morning inspection confirmed that the launch structure was covered in foot-long icicles, and no one knew what would happen if they broke off and became sharp debris. The risks were deemed appropriate for launch.
The Commission ultimately flagged the root cause of the accident as “a serious flaw in the decision-making process leading up to the launch.” Seven lives could have seen saved if concerns about the O-rings had reached the right people, or if Thiokol had worried more about safety than satisfying its major customer. But this was only part of the accident’s cause. There remained the question of why NASA didn’t delay the launch.
NASA Should Have Delayed the Launch, But PR Concerns Won Out
The space shuttle was the realization of NASA’s long-standing goal of reusability. Touted as the program that would truly open space for human exploration, it promised to turn spaceflight into something akin to air travel. Orbiters would be refurbished between missions to keep the overall program cost down and number of missions per year up.
But five years after the inaugural launch, the program averaged just five missions a year as the agency was forced to acknowledge that four orbiters weren’t enough for its original ambitious schedule.
There were some notable parts of the program: NASA had diversified its astronaut corps with scientists, women and people of color, but this wasn’t enough to sustain public interest. The missions were still esoteric and infrequent—which, coupled with NASA’s insistence that spaceflight was routine, gave people little reason to care.
When the world perked up at the news that a teacher would be flying in space, what NASA needed more than anything was a win. The mission had already been delayed from mid-1985 to early 1986, and that Tuesday was the only real option NASA had to launch. There were technical considerations: the satellites and science payloads on board had to be deployed at certain times.
The publicity goals, however, weighed heavier. According to the mission plan, Christa McAuliffe would broadcast a lesson live from orbit on her fourth day in space. A Tuesday launch meant a Friday broadcast, but a Wednesday launch meant a Saturday broadcast, when no students were in school. NASA needed the publicity of her broadcast.
Another factor was political. President Ronald Reagan was due to mention McAuliffe and the Teacher in Space in his State of the Union address on Tuesday night. If the launch was delayed, NASA would miss out on another big public mention. If the agency was going to justify continued spending on the program, Challenger had to launch on time.
There had never really been any thought of delaying the launch. NASA had leaned on its past successes as evidence that it was master over technology. But Challenger showed that technology can easily turn on its creator.
Spaceflight After Challenger
It was nearly three years before NASA launched another shuttle mission. In the interim, a handful of changes were recommended—some technical, but most focusing on repairing the damaged communications pathways, management culture and safety organization at NASA.
America’s relationship with spaceflight would be harder to fix. Challenger was the beginning of the end in a lot of ways. The nation that had watched NASA land men on the moon just 11 years after its inception expected a space station, Mars missions and even space tourism in short order. Instead it got a problematic vehicle that failed to deliver on its promises and a harsh reminder that spaceflight isn’t air travel. It may never be truly routine, and the average person may never have a chance to see the Earth from orbit.
But that doesn’t mean people aren’t chasing that dream.
Decades after the loss of Challenger, space continues to capture the public imagination. Private companies funded by some of the world’s most well-known billionaire entrepreneurs are honing their own systems taking advantage of modern construction methods, and renewing the promise of affordable and routine spaceflight. NASA, meanwhile, is developing a new generation of spacecraft and rockets with the same goal of sending humans to other planets.
As private companies and NASA take the next big steps in space, no one can forget the inescapable reality that spaceflight is risky. When Apollo went to the moon, it had the rule of “three nines:” every system had to be 99.9 percent safe to minimize risk, meaning the risk was there. And it will always be there. The key is to remember the lessons learned, that communication is vital with big technologies, and publicity pressures are never worth the risk of life. The best way to honor the men and women who gave their lives in the pursuit of space exploration: give them the chance to push humanity towards a better, safer future in space.
Amy Shira Teitel is a spaceflight historian, author of Breaking the Chains of Gravity.
