Fiona Pepper

It was like, is it supposed to do that?

We know that the solid rocket booster's come off, but it became quickly apparent that this wasn't right and this didn't look right.

and people in the flight control room obviously were aware that this had gone catastrophically wrong and there were no survivors.

There was no hope that the seven crew on board, including this incredible teacher, could have survived this space shuttle breaking up and then plunging into the Atlantic Ocean.

they'd had 24 successful launches and to this point so people people had confidence that this was working and and that this was um I don't know it was a day of celebration and this launch was slightly different you know there were crew going up to do scientific work but there was a teacher on board who was going to speak to you in your classroom and

It was profound sadness.

And when you speak to people, although, you know, it's 40 years since the Challenger disaster, it's kind of a 9-11 moment where people can describe exactly where they were when they saw that footage or when they heard the news, when they were driving the car.

And a lot of people thought it was like a science fiction movie or when they turned on the TV and they saw images of this space shuttle breaking apart, they didn't kind of know what they were looking at.

It was otherworldly, I suppose.

And yeah, it wasn't just Americans.

It was people all around the world.

Yeah, yeah.

So people went, well, it must have been the ice from the night before.

And, you know, that was a contributing factor.

From looking at the launch footage, there was a thing called blow-by where a very hot gas had kind of escaped from one of the joints in the solid rocket boosters and that had led to this catastrophic failure.

So an O-ring is massive.

I can't remember the exact dimensions, but, you know, you think of these 15-story high solid rocket boosters.

They're broken up into seven segments, and at each joint there are O-rings inside of them.

So they're, like, as thin as your little finger but, like, metres in diameter because they have to kind of fit.

This big rubber ring that fits around the edge of this solid rocket booster to seal that joint.