February 27, 2015 12:45 PM EST
L eonard Nimoy, who won over an obsessive fan-base with his logical, pointy-eared Mr. Spock on Star Trek , died on Feb. 27. He was 83.
His final tweet from Monday was exceptionally poignant:
Nimoy signed all his tweets “LLAP” or “Live Long and Prosper,” his character’s catchphrase from the Star Trek series and films.
Nimoy had announced via Twitter last year that he had been diagnosed with COPD, a chronic respiratory disease caused by smoking that has no cure. He encouraged his followers to stop smoking.
Read next: This Is How the New Spock Said Goodbye to the Old Spock
See Leonard Nimoy's Long and Prosperous Life in Photos Leonard Nimoy in The Outer Limits in 1964. ABC/Getty Images Leonard Nimoy with wife Sandra Zober attend an event in Los Angeles,Calif. in 1966. Michael Ochs Archives—Getty Images Leonard Nimoy, circa 1968. Silver Screen Collection/Getty Images Leonard Nimoy as Mr. Spock and William Shatner as Captain James T. Kirk in season 3 of Star Trek in 1968. CBS/Getty Images Leonard Nimoy as Paris and Lee Meriwether as Tracey in Mission Impossible in 1969. CBS/Getty Images Leonard Nimoy in Catlow , 1971. Silver Screen Collection/Getty Images Leonard Nimoy in The Alpha Caper in 1973 Everett NASA's space shuttle Enterprise rolled out of the Palmdale manufacturing facilities and was greeted by NASA officials and cast members from Star Trek in 1976. From left: NASA Administrator Dr. James D. Fletcher; DeForest Kelley, who portrayed Dr. "Bones" McCoy on the series; George Takei (Mr. Sulu); James Doohan (Chief Engineer Montgomery "Scotty" Scott); Nichelle Nichols (Lt. Uhura); Leonard Nimoy (Mr. Spock); series creator Gene Roddenberry; an unnamed NASA official; and, Walter Koenig (Ensign Pavel Chekov). NASA Leonard Nimoy hosts The Unexplained in 1976. Everett Leonard Nimoy as Mr. Spock in Star Trek III: The Search for Spock in 1984. Paramount/Everett Leonard Nimoy guest stars in The Big Bang Theory . CBS/Getty Images Leonard Nimoy guest stars on Fringe Fox Leonard Nimoy and Luke Wilson, presenters during 5th Annual TV Land Awards - Show at Barker Hangar in Santa Monica, Calif. in 2007. Chris Polk—FilmMagic/Getty Images Leonard Nimoy guest stars as Mr. Spock in Star Trek in 2009. Paramount Listen to the most important stories of the day.
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