Stephen Hawking, 76, was known for this work in the scientific field and his discoveries over the years and renowned as one of the greatest scientists of all time.
Some of his theories included radiation from black holes, as well as being the first to use the theory of relativity explaining cosmology. He was author of the best-selling book A Brief History of Time in 1988.
However he was diagnosed with motor neurone disease at an early age, with his first symptoms being discovered when he was at Oxford university. He was diagnosed when he was 21 in 1963.
Despite having a life expectancy of just two years, he went on to live another 55 years.
But how much was Stephen Hawking worth?
The professor accumulated $ 20 million (£14 million) upon his death, according to celebritynetworth.com
His work includes a number of best-selling books alongside his research on black holes and cosmology.
He was also the director of research at the Center for Theoretical Cosmology at the University of Cambridge.
According to Inverse, his work has also meant a number of large fees for his speeches and awards, one of which was the Fundamental Physics Prize in which $ 3 million (£2.1 million) in cash was awarded.
Hawking featured in a number of TV shows as himself. Hawking first appeared in popular media in 1993 on Star Trek, followed by The Simpsons in 1999.
He also guest starred in Futurama and the Big Bang Theory, as well as Father Ted and using his voice for other shows and sitcoms.
The story of his life was made into a film in 2014, called The Theory of Everything in which Eddie Redmayne, who played the professor, won an Academy Award for the role.
The professor has been married twice. He met his first wife Jane Wilde at university, who was a friend of his sister.
They married in 1964, and had three children together: Robert, Lucy and Timothy.
However they divorced in 1995, when Hawking fell in love with his nurse Elaine Mason.
They married that year, only to divorce in 2006.
