Everyone knew of Stephen Hawking's cosmic brilliance, but few could comprehend it. Not even top-notch astronomers. Hawking, who died at his home in Cambridge, England, on Wednesday at age 76, became the public face of science genius. He dies at his home, his family said. He appeared on "Star Trek: The Next Generation," voiced himself in "The Simpsons" cartoon series and wrote the best seller "A Br