As an Oxford student, Stephen Hawking never expected that people across the world would know his name, or that his hobby of stargazing would lead him to be one of the world s greatest scientists. Stephen Hawking made cosmology, or the study of the universe, accessible to everyone. 
He was diagnosed with amyotrophic lateral sclerosis at the age of twenty-one, but didn t let that stop him from receiving a graduate degree from Cambridge and going on to be an expert in the scientific origin of the universe and black holes. 
Hawking is best known for writing A Brief History of Time, which explained cosmology in non-scientific terms so that non-scientists could understand it.