Caroll Spinney isn't a household name, but he should be. He's the puppeteer behind Big Bird and Oscar The Grouch. He passed away yesterday at the age of 85.

His family says he'd been living with a "movement disorder" called dystonia for some time, currently there's no word on the cause of his death.

He was with Sesame Street when it started in 1969, and only retired last year.  Spinney was the man behind arguably the two most recognizable Sesame Street characters of all time for half a century.

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He stopped getting inside the Big Bird costume in 2015, because it was too physically demanding. The head weighs five pounds, and he had to hold it up with his right arm, while working the mouth and facial expressions with his hand.

But he continued providing the voice until his retirement.

He won five Daytime Emmys and a lifetime achievement award from the National Academy of Television Arts & Sciences. He was also the subject of a documentary in 2014, called "I Am Big Bird".

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This is crazy, Spinney was invited to fly on the Space Shuttle Challenger as Big Bird in 1986, but the idea was scrapped because there wasn't enough room for the costume. The Challenger exploded 73 seconds into its flight.