[0:00]
Two men knew that the space shuttle challenger was going to explode on January 28th, 1986. And they did everything they could to stop it, but they couldn't. Here's what happened. On the morning launch, Bob Evling and Roger Boyce Jolie called their boss at Morton Thiault and told him they need to get NASA on the phone. The space shuttle was gonna blow up, and they should know. They designed the rocket. The space shuttle used two different types of rockets to get it to outer space. Inside of this large tank was liquid rocket fuel that was fed through the space shuttle 
[0:30]
to the space shuttle's own engines and then expelled out the back. But there were additionally two rocket boosters that were solid fuel rocket boosters. And these were designed and built by Morton Thiokol and by Roger and Bob. Now, these things were so big, they couldn't be manufactured in one piece. And so what they did was they made a series of small little pieces. And then stack them together like a pancake. To make a completely sealed connection between each component of the rocket. 
[1:00]
They used an O ring. How an O ring works is you put it into a little groove, and it's bigger than the groove. Then when you apply pressure from another piece of metal, it expands out and completely seals the area. Now, we use the exact same setup. Scuba diving inside of there. That black ring, it's an O ring onto This huge tank of compressed air. Think of it as a rocket. I can take another piece of metal, attach it, apply pressure. The O ring will expand and create an airtight connection. But watch what happens if I cut a small nick in that O ring. 
[1:33]
Now Alternate Air is able to get out through that connection. That's bad. Bob and Roger knew that the exact same thing was going to happen to the challenger. You see, in order for an O ring to work, it has to be pliable when you push on it. Overnight at Cape Canaveral, the temperature had dropped to freezing. And when that happens, the rubber becomes brittle and could no longer bend, meaning that it could no longer fill that gap. When Bob and Roger explained what was going to happen to their bosses at Martin Marietta, 
[2:04]
they agreed and immediately called NASA and told them to halt the launch. But three things went wrong during that phone call. The first thing was that NASA let outside pressures other than engineering and safety affect their decision. You see, there was a lot of pressure on NASA to get that space shuttle up. Krista Mcauliffe was also on board, the first school teacher to go into space. And it was scheduled to be broadcast to classrooms all over the country. And Ronald Reagan had a state of the union address coming up where he wanted to talk about the space shuttle being in the sky. 
[2:36]
They needed to get it up there. when Martin Thigpen explained the problem to Lawrence Malloy at NASA, he lashed out. And he says, well, when do you want me to launch this? Next April. And that's when price became a factor. NASA was Martin Thigpen's largest client, and they were mad. Which leads us to the second problem. The people who made the decision to go were not the people who knew the most about the issue. They were higher UPS who knew a lot about the program as a whole. But didn't understand this issue. 
[3:08]
And that lack of expertise would make them grab this, the wrong chart. You see, NASA knew that a failure of the O rings could result in an explosion of the space shuttle. They had done their own internal analysis and concluded that the chance of that happening was only one out of every 100,000 launches. Point zero zero one %. But there was a flaw in that analysis. See, what they had done is they'd look at the O rings after every single launch. And they could tell that every once in a while there was some defect that manifested in the O rings. 
[3:41]
This is the number of defects they found on any given launch. And this is the temperature of the launch. They looked at this data and said, look, we have problems with the O rings when it's cold. But we also have problems with the O rings when it's warm. Therefore, Temperature must not be what's causing the issue, so we can rule that out. But what they didn't look at is the number of times there were no issues with the O rings. So there had been nine different times that the space shuttle flew with no problems, 
[4:13]
and all of them was when it was warm. What that means is that above 65 degrees, there was only a 15% chance there would be some issue with the O ring. Below 65 degrees, that rose to 100%. If this graph had been properly prepared, it would have shown this drastic increase as things cooled off and the challenger launch. It wasn't even on the chart. It was clear over here. So NASA pushed back on the Martin Thoracol executives, 
[4:45]
who went back to Bob and Roger and tried to get them to change their opinions. But Bob and Roger refused. They knew what would happen. And Morton Thiokol executives, knowing where their paycheck came from, decided to tell NASA that it was okay to go ahead anyway. And so the decision was made to launch. Hearing the news, Bob jumped into the car with his daughter Sophia and drove to Morton Thiokol to try and do something. On the way, he told her, the challenger is going to explode. Everybody's going to die. 
[5:15]
Point six, nine, eight seconds into the flight, right here can be seen on the cameras a little bit of smoke. That was the O ring failing. Fifty eight seconds into the flight, and the space shuttle begins to rotate. As it does, it puts stress on these joints, and at 58 seconds in, you can see flames start to come out of this joint right here. That was a critical location because there was a strut that was located nearby, attaching the booster rocket to the rest of the assembly. 
[5:47]
At 73 seconds in, that strut burns through, and as it does, the pressure of this rocket pushes out this way, which brings this end in, and it goes into and punctures the main tank, and it explodes. This is where the crew is. The crew assembly remained intact. It would fall until three minutes and 58 seconds into the flight, until it hit the ocean at 200 miles per hour. 
[6:19]
NASA has been unable to determine, or if they have, they have not shared, whether or not the crew was still alive when they hit the water. Following the explosion, two anonymous sources within Morton Thiokol contacted two journalists with MPR and explained to them exactly what had happened, how it had happened, and why it had happened. MPR would safeguard the identity of those two whistle blowers for decades, protecting them from retaliation from the government 
[6:50]
and from Morton's ire. Call in 2006, as the 30th anniversary of the challenger explosion approached, one of the journalists went to talk with one of his anonymous sources, and it was only then that permission was given. To reveal their identity. They were Bob and Roger. And it was only then that the reporter began to understand the incredible burden that these men had carried their whole life. Bob told him that in the whole thing, god made one mistake. He had selected Bob to be the man to raise the award. 
[7:23]
And he said, quote, god chose a loser. End quote. He had internalized the failure of stopping the launch. To him that it was his responsibility that those seven people had died. Following the 2,006 article, people from all over the world wrote to tell him that it wasn't his fault. Flight engineer Robert Lund and NASA's John Hardy were among those who reached out and told him that responsibility for that decision did not rest with him. 
[7:54]
It rested with them. It was not his burden to bear. Bob died at age 89, and his daughter, looking back at that outpouring of support that he received, said, it was as if he got permission from the world. He was able to let that part of his life go. He was able to die in peace, knowing that he had done all that he could have done.