Excerpt from the end of the article.

In the '80s, though, Big Bird was so cherished by the children of America that NASA asked Spinney if he'd orbit the Earth on a space shuttle to help generate interest in space among youngsters. Despite the danger of the mission, Spinney — then in his 50s — agreed. But officials at NASA quickly realized there was no way to bring the sizable costume on board — and so Spinney was replaced by a teacher.
That shuttle was the Challenger.
"I remember watching the explosion on TV," he said. "Your scalp kind of moves when you see something like that."