The actor lost his battle with chronic obstructive pulmonary disease at his home in Bel Air, Los Angeles on Friday (27Feb15), aged 83, and stars and dignitaries have been hitting social media to offer their thoughts about Nimoy's passing.
They included his former Star Trek pals George Takei and William Shatner and Zachary Quinto, who played the young Mr. Spock in J.J. Abrams' films Star Trek and Star Trek Into Darkness.
And late on Friday, Obama offered his tribute, wrote, "Long before being nerdy was cool, there was Leonard Nimoy. Leonard was a lifelong lover of the arts and humanities, a supporter of the sciences, generous with his talent and his time. And of course, Leonard was Spock. Cool, logical, big-eared and level-headed, the center of Star Trek’s optimistic, inclusive vision of humanity’s future.
"I loved Spock. In 2007, I had the chance to meet Leonard in person. It was only logical to greet him with the Vulcan salute, the universal sign for 'Live long and prosper'. And after 83 years on this planet - and on his visits to many others - it’s clear Leonard Nimoy did just that. Michelle and I join his family, friends, and countless fans who miss him so dearly today."