For over 50 years, Sesame Street’s Big Bird has been one of the most iconic and beloved children’s characters. The 8-foot 2-inch (249 cm) bright yellow bird has been teaching children how to read and develop an interest in art, poetry, and any number of extracurricular activities.

And he very nearly traumatized millions of children by dying tragically in space.

For most of Big Bird’s existence, he owed his voice and mobility to Carroll Spinney, the actor inside the massive bird costume. In addition to bringing Big Bird to life, Spinney was the first puppeteer to perform Oscar the Grouch.

Big Bird quickly became the biggest star — both in terms of size and popularity — of Sesame Street. Within ten years, more than 9 million children under the age of six were watching Big Bird and his friends every day, including 90% of all children from low-income inner-city homes.

Attempting to capitalize upon Big Bird’s popularity and influence, NASA invited Spinney to take part in the Space Flight Participation Program. The success of the reusable space shuttle had made space flight appear to be routine and uninteresting. NASA hoped that sending civilians into space would boost public awareness and excitement about the space program.

NASA hoped that some Sesame Street episodes from space, showing Big Bird learning all about the space shuttle while floating weightlessly in orbit, would inspire a new generation of astronauts and ensure public support of the space program.

Although the prospect of allowing Big Bird the opportunity to be able to fly had its merits, the biggest hindrance was the fact that Big Bird is — well — BIG. The massive puppet costume would take up quite a bit of space in an already-crowded space shuttle. Ultimately, the plans for Big Bird’s big space adventure were grounded.

Although disappointed at the loss of the Sesame Street angle to a shuttle mission, NASA still thought there could be great educational value for children in a space mission. For this reason, NASA turned its attention away from celebrities and instead sought out a teacher to take Big Bird’s place. The person chosen for the honor was a 37-year-old social studies teacher from New Hampshire named Christa McAuliffe.

That’s why, on January 28, 1986, it was McAuliffe’s social studies class — rather than the 9 million children of the Sesame Street audience — who watched with barely-suppressed excitement as the space shuttle Challenger lifted off with their teacher on board. Seventy-three seconds later, the mission came to a tragic end as Challenger exploded, killing McAuliffe and her six crewmates.

Among those watching was Carroll Spinney. “We just stood there crying,” he said. He would go on to continue to play Big Bird for another thirty-two years. He retired in 2018 and died the next year of natural causes at the age of 85.

Big Bird never got his chance to fly in space. Neither did Sesame Street have to figure out how to explain to millions of children why they would never see their big, yellow friend again.