It’s The Anniversary Of The Challenger Disaster So Let’s Take A Moment To Remember

Like many of my generation, I watched the space shuttle Challenger explode on live television, while I was at school. I remember it very well, because I was a colossal space geek as a kid, and still am, as a kid well into his 50s. I was excited because it was unusual to watch a space launch in school in 1986 – the Space Shuttle program, while never coming close to reaching its predicted launch schedule of 50 or more flights per year, nevertheless proved capable of launching more frequent crewed space missions than ever before, with a peak just the year prior to the disaster of nine missions. Watching space shuttles climb that tower of flame and smoke into space had become almost routine. Maybe not “almost”; I think for most people a shuttle launch barely registered as news anymore. But this time there was a teacher aboard, so all of the schools paid attention.

The inclusion of that teacher was a huge deal; I remember the search that led to the selection of Christa McAuliffe, but more importantly I remember how it felt knowing that this was a real, normal person going up on that shuttle. She was just a teacher! I knew what teachers were like, I saw them get flustered and chain smoke in the teacher’s lounge and look exhausted and exasperated by me an all my fellow idiot kids – these were not superhumans, like I imagined astronauts to be, or at least DeLuxe-trim-level humans. They were people, and seeing a normal, bright but likely flawed person go on the shuttle really made it feel like things were changing, and soon space travel would be something we could all aspire to.

Of course, that’s not how it played out. I remember that I was in art class, which I loved, and I remember the big CRT television cart getting wheeled into the room so everyone could watch. I’d seen shuttle launches many times, and had memorized the diagrams and charts that were published in National Geographic, so I eagerly awaited each expected stage of the launch – the three main engines on the orbiter firing first, making their smokeless cones of barely-visible exhaust flame, then the massive bursts from the pair of solid rocket boosters mounted to each side, each one belching out huge columns of white clouds as they flung the whole shuttle stack into the sky, and then finally the two spent boosters ejecting, leaving the orbiter and its big orange fuel tank to continue ascending alone, until the cameras could no longer see it.

What I expected was not what I got, of course, and as soon as I saw that big ball of cloudy smoke and the two boosters careening around wildly and uncontrolled, I knew something was off. I remember that strange numb feeling for a few seconds while everyone was trying to figure out what the hell was going on, the announcers on the TV seeming confused, and most of my classmates pretty oblivious. That moment seemed like a very long time, but it wasn’t.

The realization of what happened soon came, both to the voices coming from the television and in our messy art room, with its big tables and stacks of pastels and paper and clay, student’s artwork of wildly varying quality lining shelves all around. There wasn’t a big uproar in the class, just a sort of sudden hush, like a huge tarp had been thrown over everyone as we all shared a moment of realization that, sometimes, no matter how well planned, no matter how smart the people in charge are, shit goes bad.

I think to appreciate the widespread impact of the Challenger disaster, you have to remember how much the whole thing was built up, and how hard a fall it was. The shuttle program was a huge success and a huge source of pride for America. These were the first actually re-usable spacecraft (though some in the program described them more as re-salvaged, due to all of the maintenance they required) and they were so much larger and more impressive than the dinky gumdrop capsules that came before.

We’d been launching them with seeming ease many times a year, and had gotten to the point where NASA felt confident enough to send up that teacher, to great publicity; the disaster couldn’t have happened at better moment, if the goal was to remind humanity about the concept of hubris. I feel like for those of us that saw it, there was one big common takeaway, even beyond the expected feelings of loss and tragedy about those seven people whose lives were ended that day. To some degree, they knew there were risks, and they willingly took those risks to do something they genuinely loved and believed in. That doesn’t make what happened less tragic, but it makes it a little easier to understand.

No, I think the more unexpected lesson that we learned then is that, to some degree, we’re all winging it. The people we trust in positions of authorities are still people, flawed people, and they make mistakes and are as susceptible to being influenced by the wrong things as any of us. I think there’s some seeds of the strains of mistrust of authority and expertise that many of us feel today, rationally or otherwise. And I also think once the initial shock and sadness filtered away, we were left with a good bit of cynicism. I remember that just a few days after the tragedy, gallows humor jokes about it were already spreading around the lunchroom. I’m pretty sure it was later that week when I first heard a kid ask “Why does NASA only serve Sprite on the space shuttle? Because they can’t get 7-Up!”

I mean, it’s a well-crafted joke, and gallows humor is always a part of dealing with a tragedy, but there is darkness beneath it, and I think we’re still dealing with some of those repercussions.

The reason the disaster happened was because of what seems like a small detail in the construction of the solid rocket boosters (SRB). The boosters were pretty remarkable machines – the largest solid rockets ever built, designed to be reused, and were constructed in several segments. The interfaces between those segments were more complex than you may realize, and relied on some rubber O-rings (can there be any type of ring other than an “O?”) to keep things sealed even while things were expanding and contracting based on thermal loads.

NASA and Morton Thiokol (who built the SRBs) were aware that these rings that sealed the joints in the SRB segments could have issues properly sealing due to loss of elasticity at low temperatures since the 1970s, but the issues were never thought to be particularly severe. NASA had observed these joint seals venting soot on other missions without further incident, and took this as proof that the issue was one that could be tolerated, instead of a symptom of something larger.

On the day of the launch, ambient temperatures were as low as 18 °F; the previously coldest shuttle launch had temperatures above 50°, and Morton Thiokol engineers actually expressed concerns to NASA about the elasticity of the O-rings at those temperatures before the launch, and were only confident in launching in temperatures 51° or higher; NASA managers didn’t accept these concerns as valid, and questioned if they expected the launch to be delayed until April.

The inability of these rubber O-rings to seal the segments caused plumes of hot gases to escape, which melted through the external fuel tank, causing it to break apart, and, from there, the entire assembly to be destroyed, crewed orbiter and all.

Famous physicist Richard Feynman demonstrated what happened to these O-rings very dramatically during one of the hearings about the disaster. He arranged to get a sample O-ring and place it in a clamp, then placed that into a glass of ice water, bringing the O-ring down to 32° F. He was then able to show, right there, that the frozen O-ring lost most of its elasticity and ability to return to its original shape at those low temperatures:

I think most of us know all of this by now; it’s been 40 years, after all. But I think it’s worth remembering, to honor the brave explorers who happily climbed into that delta-winged flying brick strapped to a massive column of fuel and two colossal firecrackers with only the goals of learning more about our universe, and how we can figure out how to explore it further, but also to remember that sometimes even the smartest people, the ones who actually make amazing things happen, make mistakes.

Sometimes huge mistakes. But that doesn’t diminish what they accomplish; if anything, it makes every success more impressive. The Challenger Disaster was a tragedy, but I do think we learned something. Some very specific things about solid rocket boosters of course – evolved versions of these same boosters are used on the new Space Launch System (SLS) rocket that will be sending people around the moon in a few months – but also something about, I don’t know, confidence? Over confidence?

Everything is so complicated. A bit of cold weather is what caused the failure of one of the most complex and carefully-engineered machines in all of human history. Everything is connected, every little thing affects every other little thing and on and on in a cascade of cause and effect that makes you dizzy. And yet somehow, we manage to pull things off, anyway.

We grope, we take risks, we fail, we try again. Seeing this disaster happen was sobering and shattered some illusions, but maybe those illusions were ones that should be shattered. Maybe we should have hope in things and people and ability, but not a blind hope. Maybe knowing that things can go wrong, horribly wrong, is a reality we should all keep in the back of our minds, and find a way to know it’s there and keep going anyway.

I’m not entirely sure of how the Challenger Disaster affected me or the so many others who saw it, but I know it did, somehow. I just hope I figure out how to turn it into something that honors those who died, and makes us better or smarter or something. At least not worse.