But -- as anyone who saw "Star Trek III: The Search for Spock" can attest -- you can't keep Leonard Nimoy down for long.
On Thursday, just five days after he celebrated his 80th birthday, Entertainment Weekly reported that Nimoy would be returning to acting in this summer's "Transformers: Dark of the Moon." And appropriately, it's a role that returns him to outer space.
Nimoy will be providing the voice of Sentinel Prime, the giant robot seen lying dormant on the surface of the moon in the first trailer for the movie. Sentinel Prime was discovered by the Apollo 11 astronauts on their secret mission during the first moon landing (according to the movie). The character of Sentinel Prime was introduced in the original Marvel Comics as the previous Autobot leader who passed the Matrix of Leadership to Optimus Prime before he died. Sentinel reappeared in several different incarnations in subsequent comics and animated shows, sometimes as a predecesor to Optimus and sometimes as his contemporary. In "Dark of the Moon," Sentinel is a "big brother and mentor" to Optimus, according to Empire Magazine.