Stephen Hawking's death on Wednesday left the universe a slightly dimmer place but lit up social media as academics, politicians and celebrities alike praised a scientist whose appeal crossed time, space and cultural boundaries.
Here is a collection of tweets reacting to Hawking's death:
"His theories unlocked a universe of possibilities that we and the world are exploring. May you keep flying like superman in microgravity, as you said to astronauts on @Space_Station in 2014."
Neil De Grasse Tyson, American astrophysicist (@neiltyson)
"His passing has left an intellectual vacuum in his wake. But it's not empty. Think of it as a kind of vacuum energy permeating the fabric of spacetime that defies measure."
Chris Hadfield, Canadian astronaut (@Cmdr_Hadfield)
"Genius is so fine and rare. Goodbye Professor Hawking. You inspired and taught us all."
Tanya Harrison, scientist, director of ASU New Space (@tanyaofmars)
"He was a huge inspiration to me as a teen when I was in and out of wheelchairs from my illness—seeing him keeping on doing science kept me going. So thank you, Prof. Hawking, for giving people like me the hope and strength to keep trying to understand the beauty of our universe even through the darkness of pain."
Lawrence M. Krauss, theoretical physicist (@LKrauss1)
"A star just went out in the cosmos. We have lost an amazing human being. Stephen Hawking fought and tamed the cosmos bravely for 76 years and taught us all something important about what it truly means to celebrate about being human. I will miss him."
Narendra Modi, prime minister of India (@narendramodi)
"Professor Stephen Hawking was an outstanding scientist and academic. His grit and tenacity inspired people all over the world. His demise is anguishing. Professor Hawking’s pioneering work made our world a better place. May his soul rest in peace."
Samatha Power, Former US Ambassador to the UN (@SamanthaJPower)
"R.I.P. Stephen Hawking. Among his many profound contributions to this world was this simple sentiment: 'It would not be much of a universe if it wasn’t home to the people you love.'"
Sundar Pichai, CEO of Google (@sundarpichai)
"The world has lost a beautiful mind and a brilliant scientist. RIP Stephen Hawking."
Errol Morris, director, made 1991 "A Brief History of Time" documentary with Hawking (@errolmorris)
"It had to happen, eventually. We were lucky to have him for so long, and I was lucky to be able to work with him. A truly fabulous human being. Stephen Hawking. Funny, perverse, and, of course, brilliant."
Dan Rather, veteran journalist (@DanRather)
"Our world has lost a shining light. Stephen Hawking defied expectation. Blessed with a brilliant mind and uncommon grace, he opened so many minds to the wonders of our universe. Courageous and unbowed by adversity, he believed deeply in the power (of) reason. May he rest in peace."
Larry King, veteran journalist (@kingsthings)
"I had the honor of interviewing Stephen Hawking several times. He was inspirational, always optimistic and had a wicked sense of humor too. Humanity is richer for his life and curiosity. Rest well dear professor."
Adam Savage, former co-host of Myth Busters (@donttrythis)
"Nooo! I'm so so sad to see the news about Stephen Hawking, and at the same time I imagine him learning something new for the last time, and smiling, and I know that the world was richer with him in it."
Katy Perry, American singer (@katyperry)
"There's a big black hole in my heart hours before Pi Day. Rest in Peace Stephen hawking"
Kumail Nanjiani, comedian, actor and director (@kumailn)
"RIP Stephen Hawking. Genuinely very sad to hear that. If you haven’t, read A Brief History of Time. It’ll make the world feel more amazing and beautiful and strange. It’ll also make you feel smart and stupid all at once."
Dana Goldberg, American comedienne (@DGCOmedy)
"I rarely cry at the death of people I don’t know personally, but the announcement of the passing of Stephen Hawking just brought tears to my eyes. What a beautiful genius this earth has lost."
Macaulay Culkin, American actor (@IncredibleCulk)
"I just heard about Stephen Hawking's passing. He was both a genius and my favorite Simpsons character. We'll miss you, buddy."
Steve Gleason, former NFL player who also has ALS (@TeamGleason)
"Stephen Hawking inspired me before ALS - to keep asking questions, seeking answers, and understanding the cosmic perspective. But since ALS, he saved my life with his example - people diagnosed with ALS can continue to live productive & purposeful lives for decades."