NBC - After years of battling ALS, scientist Stephen Hawking, passed away Tuesday night in London.
Hawking spent the majority of his life exploring the theories of space and time, all from the constraints of a wheelchair. He was able to demonstrate Einstein's General Theory of Relativity, implying space and time would have a beginning in the big bang and an end in black holes.
All this while battling a debilitating disease. He was diagnosed with ALS in his early twenties. Still, Hawking rose to the top in both physics and mathematics.
In 1979, Cambridge named him the Lucasian professor of mathematics, a distinguished post once held by Sir Isaac Newton more than 300 years earlier.
The mainstream was alerted to his brilliance with his best-selling book, "A Brief History of Time."
Late in life, Hawking put forth a new theory on black holes, admitting he may have been wrong in the past.
Hawking became known for his computerized wheelchair and voices synthesizer. That allowed the scientist to communicate with others.
Despite his illness, he was able to bring about landmark advances in physics and mathematics.
Stephen Hawking leaves three children and three grandchildren.