(CNN) -- Acclaimed British physicist Stephen Hawking has died at the age of 76.
He was widely considered the world's greatest living scientists. Hawking was widely known both in scientific circles and popular culture.
Hawking's landmark book "A Brief History of Time" explained astrophysics in lay term, has sold 10 million copies.
He lived with A-L-S since 1963. At the time of his diagnosis, his doctors gave him just a few years to life. Hawking told CNN in 2008 he believed if human kind can avoid disaster on earth for the next 2-hundred years or so, it would be best to learn to live in space.