Stephen Hillenburg, the creator of Nickelodeon's "SpongeBob SquarePants," has died of ALS, the network confirmed.
Hillenburg, 57, last year revealed he had been diagnosed with amyotrophic lateral sclerosis, more commonly known as ALS or Lou Gehrig's disease.
In a tweet on Tuesday, Nickelodeon said, "We are observing a moment of silence to honor his life and work."
Celebrities and notable figures who have recently passed away
Hillenburg conceived, wrote, produced and directed the animated series, which began in 1999 and is currently in its eleventh season. The series, which stars voice actor Tom Kenny in the title role, follows a gregarious sponge who "lives in a pineapple under the sea" and all his ocean-residing friends.
Prior to "SpongeBob," Hillenburg worked as a marine biology teacher. When he revealed his diagnosis to Variety, he said he'd continue to work on the show and his other passions for as long as he could.
ALS is a disease that affects nerve cells in the brain and spinal cord. It progressively kills the neurons that control muscles, eventually leading to paralysis. The fight for a cure came into the spotlight in 2014 with the ice bucket challenge, which raised more than $100 million. Scientists are still racing to find a cure.
The Associated Press contributed to this story.