Despite a long battle with amyotrophic lateral sclerosis (ALS), a progressive neurodegenerative disease that attacks the nerve cells in the spinal cord and brain, leading to paralysis, Hawking was able to bring to light several groundbreaking theories in the field of quantum physics, while making the complex field accessible to millions through a series of bestselling books.

Hawking was diagnosed with ALS, also known as Lou Gehrig's disease, in 1963, after experiencing difficulties with his movements in his final year at Oxford University. He was given just two years to live by doctors at the time, but went on to live with it for more than 50 years, an incredibly long time for an ALS sufferer. Unfortunately there is still very little known about the causes of ALS, and currently no cure. You may remember the successful awareness raising campaign for ALS that went viral a couple of years back, the ‘Ice Bucket Challenge.’ $115 million dollars were raised for research into the disease, resulting in some important discoveries.

Devastated by his diagnosis, Hawking nevertheless continued his work while his physical capabilities declined. Despite all of the setbacks he encountered, he always found ways to overcome them. He got around in a motorized wheelchair, and was able to communicate through an automated speech system, which gave him his iconic, computerized voice.

As well as his achievements in the field of quantum physics, and his determined quest to find a ‘unified theory’ that would aid us in our goal to gain a ‘complete understanding of the events around us, and of our own existence,’ Hawking’s celebrity helped to popularize and bring cosmology to a whole new generation of people.

His bestselling books and appearances on TV shows such as The Simpsons and The Big Bang Theory helped to promote an enthusiasm for science that will endure well beyond his passing. He has opened the door for present and future scientists through his brilliant theories and discoveries, his determination in the face of adversity, and his inspiration to millions of people all over the world. He will be sorely missed.