Hawking (1942-2018) is one of the most prominent theoretical physicists and cosmologists of the 20th and 21st centuries. His papers on the origin of the universe and on black holes changed science’s views on how reality works. Hawking was one of the youngest scientists admitted to the Royal Society, Britain’s premier science academy, and he held the Lucasian Chair in mathematics at Cambridge, a position once held by Newton. For many decades, Hawking had a fruitful working relationship with the California Institute of Technology.

In 1963, at age 21, Hawking was diagnosed with a rare form of the motor neuron disease ALS (or Lou Gehrig’s disease), which irreversibly paralyzes the body’s major systems. Increasingly reliant upon technology, such as a motorized wheelchair, Hawking learned to communicate via a computer system. He maintained his professorship at Cambridge for over 30 years, was a prolific author, and gave talks and lectures all over the world. Hawking was ambivalent about his role as a disability activist, preferring to focus on his research. Nevertheless, Hawking lived with ALS for 55 years after being given a 2-year life expectancy at his initial diagnosis, and his public profile and career achievements brought increased awareness to ALS.

A lifelong atheist and supporter of England’s Labor Party, Hawking believed humanity was likely to destroy itself through war, environmental catastrophe, or misaligned artificial intelligence and that colonizing other planets was a chief means of sidestepping the worst effects of such disasters.