Stephen Hillenburg, the former marine biology teacher whose love for all things aquatic inspired him to create SpongeBob SquarePants, has died at age 57, Nickelodeon said Tuesday.
"We are sad to share the news of the passing of Stephen Hillenburg, the creator of SpongeBob SquarePants," the network said in a statement. "Today, we are observing a moment of silence to honor his life and work."
In 2017, Hillenburg told Variety he'd been diagnosed with amyotrophic lateral sclerosis.
"Anyone who knows me knows that I will continue to work on SpongeBob SquarePants and my other passions for as long as I am able," he said at the time.
Hillenburg began his animation career while still teaching marine biology, creating a comic book he called The Intertidal Zone to use with his students. He later worked on Rocko's Modern Life, where he met Tom Kenny, who voices SpongeBob.
SpongeBob SquarePants, which began airing in 1999, is the highest-rated Nickelodeon show of all time. And there have been two feature films. Its title character is a happy-go-lucky sea sponge who famously lives in a pineapple under the sea with a meowing snail named Gary, and works as a fry cook at the Krusty Krab restaurant. Pals Patrick Star, Squidward and Sandy Cheeks are just part of his underwater universe in an aquatic city called Bikini Bottom.
Fans remembered Hillenburg with numerous images from the show, many featuring a teary-eyed SpongeBob himself. One fan said he was "truly a genius," while another said Hillenburg "fueled" his childhood and nurtured his "sense of humor for years into adulthood."
Actor David Hasselhoff, who appeared as himself in the 2004 SpongeBob SquarePants Movie, also remembered Hillenburg.
"Wow what a unique and fantastic character Steve created!" Hasselhoff tweeted. "It was my pleasure and honor to be in SpongeBob The Movie and to share some great laughs with this gentleman, Shocking Loss! To this day I am stopped and flattered by people and kids who have seen me in the film."
Some fans shared memories of what the show meant to them.
In a 2012 history of the show, Kenny said that Hillenburg knew how he wanted SpongeBob's underwater universe to look right from the start.
"He asked me to look at some stuff, and it was a very well-thought-out, well-conceived bible, the only difference being that the character was called SpongeBoy," Kenny told Cartoonician. "But there were character drawings ... personality profiles, graphic studies of SpongeBob's pineapple house and Squidward's tiki head house, the Krusty Krab, a lobster-trap-shaped structure. It was typical Steve: fully realized before he even mentioned it to anyone."
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