The death of world-changing theoretical physicist Professor Stephen Hawking has prompted an outpouring of grief across the globe.
Prof Hawking, 76, died early on Wednesday morning (local time) at his home in Cambridge, his family confirmed in a statement.
Despite being diagnosed with early onset amyotrophic lateral sclerosis (ALS) in his early 20s, and initially being given two years to live, his death has come as a shock to the scientific community.
Astrophysicist Neil deGrasse Tyson paid tribute to his fellow scientist in a moving post on Twitter.
"His passing has left an intellectual vacuum in his wake. But it's not empty," he wrote.
"Think of it as a kind of vacuum energy permeating the fabric of spacetime that defies measure."
NASA recalled the time he spoke to astronauts on board the International Space Station.
"His theories unlocked a universe of possibilities that we & the world are exploring. May you keep flying like superman in microgravity, as you said to astronauts on @Space_Station in 2014."
Multiple media outlets have praised Prof Hawking as the "universe's brightest star", while Canadian astronaut Chris Hadfield wrote: "Genius is so fine and rare... You inspired and taught us all."
He's being remembered across the globe and by more than just the scientists who have already made a name for themselves.
"Stephen Hawking was who inspired my passion for science, I can't believe he's gone," one person wrote on Twitter, while another said Prof Hawking was "one of the greatest minds ever known".
Prof Hawking is survived by his three children, Lucy, Robert and Tim.