LOS ANGELES, Feb 28 ― Leonard Nimoy, best known for his portrayal of logic-bound Mr. Spock in the “Star Trek” science fiction television series and movies, died on Friday at age 83 after a battle with chronic obstructive pulmonary disease.

Here are reactions to Nimoy's death:

“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,” President Barack Obama, whose unemotional approach to problems has been likened to the character Nimoy portrayed on “Star Trek.”

“I loved him like a brother. We will all miss his humour, his talent and his capacity to love,” William Shatner, who co-starred on “Star Trek” as Captain Kirk, said in a statement.

“Today, the world lost a great man, and I lost a great friend. We return you now to the stars, Leonard. You taught us to 'Live Long And Prosper,' and you indeed did, friend. I shall miss you in so many, many ways,” “Star Trek” fellow cast member George Takei, who played Ensign Sulu, wrote on Facebook.

“My heart is broken. I love you profoundly my dear friend. And I will miss you everyday. May flights of angels sing thee to thy rest,” actor Zachary Quinto, who portrays Spock in the current “Star Trek” film series, said on website Instagram.

‘Star Trek’ television series actor Leonard Nimoy speaks at the unveiling of fellow ‘Star Trek’ actor Walter Koenig's star on the Hollywood Walk of Fame in Hollywood in this September 10, 2012, file photo. ― Reuters pic

“He was a true force of strength and his character was that of a champion,” “Star Trek” cast member Nichelle Nichols, who played Lieutenant Uhura, said in a statement. “Leonard's integrity and passion as an actor and devotion to his craft helped transport 'Star Trek' into television history. His vision and heart are bigger than the universe.”

“RIP Leonard Nimoy. So many of us at NASA were inspired by Star Trek. Boldly go...” the US National Aeronautics and Space Administration (NASA) wrote on Twitter.

“He lived long, he prospered, and he touched us all. RIP Leonard Nimoy,” Los Angeles Mayor Eric Garcetti said on Twitter.

“Leonard Nimoy created a positive role model who inspired untold numbers of viewers to learn more about the universe,” Space Foundation Chief Executive Officer Elliot Pulham said in a statement. “Many of those people are ardent space supporters and industry leaders today.” ― Reuters