The brilliant physicist has died at the age of 76.
Hawking suffered from ALS (amyotrophic lateral sclerosis), a neurodegenerative disease commonly known as Lou Gehrig's Disease, which is usually fatal within a few years. He was diagnosed in 1963, when he was 21, and doctors initially only gave him a few years to live.
You may remember him making guest appearances on some of the most popular TV shows including Big Bang Theory, The Simpsons, Futurama, and Star Trek: The Next Generation.
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