The billionaire sent a series of tweets expressing his sadness and shared memories with Hawking. In 2015, Branson offered the physicist a free ticket, which goes for $250,000, aboard his Virgin Galactic spaceflight. Last year, Hawking told Good Morning Britain that he never dreamed he'd be able to go to space and had immediately accepted Branson's offer.
Branson explained his reasoning behind the offer on his Virgin blog: "Professor Stephen Hawking is one of the people I admire most in the world," he wrote at the time. "He is the only person I have given a free ticket with Virgin Galactic, and he is signed up to fly as a Future Astronaut with us if his health permits it."
In October of last year, Branson told CNBC's Squawk Box that he expects to be in space by April of this year. Unfortunately, the late physicist will miss seeing this dream come to pass.
"Proud Stephen Hawking was a member of our @virgingalactic family," Branson wrote on his Twitter. "Sorry we didn't get him to space, but honoured he played such a meaningful role in our development."
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