Hawking defied expectations by living almost his entire adult life with amyotrophic lateral sclerosis; an affliction with a life expectancy of only two to five years after diagnosis.

Celebrity scientist Stephen Hawking died peacefully at the age of 76 in his Cambridge home in the early hours of Wednesday, March 14th, according to a spokesperson for his family.

Hawking was best known for his work in the fields of cosmology and quantum gravity, writing bestsellers like A Brief History of Time, but in recent years had gone on record with dire warnings against the reckless pursuit of advancement; maintaining that humanity must expand into space in order to survive.

"I believe that life on Earth is at an ever-increasing risk of being wiped out by a disaster such as sudden nuclear war, a genetically engineered virus, or other dangers," said Hawking. "I think the human race has no future if it doesn't go into space."

The celebrated physicist was also an ardent believer in life beyond our planet, although he was similarly cautious about being too eager to meet it.

"The idea that we are alone in the universe seems to me completely implausible and arrogant," he said. "Considering the number of planets and stars that we know exist, it's extremely unlikely that we are the only form of evolved life.

"If aliens ever visit us, I think the outcome would be much as when Christopher Columbus first landed in America, which didn't turn out very well for the Native Americans."

As for the afterlife, Hawking was not a believer.

"I believe the simplest explanation is, there is no God. No-one created the universe and no-one directs our fate," Hawking said. "This leads me to a profound realization that there probably is no heaven and no afterlife either."

"We have this one life to appreciate the grand design of the universe; and for that, I am extremely grateful."

Stephen Hawking Dead at 76