The Big Bang Theory paid tribute to Leonard Nimoy on Thursday.

Chuck Lorre Honors Leonard Nimoy On The Big Bang Theory

The nerd-friendly sitcom frequently references Nimoy’s iconic Star Trek character, Spock, and has featured cameos from many Star Trek actors. Spock comes up often in The Big Bang Theory as main character Sheldon’s personal hero. Nimoy himself never physically appeared on the show, but he did offer his voice in the 2012 episode “The Transporter Malfunction,” essentially appearing as himself.

After the end credits of Thursday night’s new Big Bang Theory episode, Executive Producer Chuck Lorre paid tribute to Nimoy with a special title card at the end of the episode. The end-credits image is usually a Chuck Lorre Productions vanity card, but instead, it was replaced by a black-and-white photo of Nimoy and a message for the actor. “The impact you had on our show and on our lives is everlasting,” read the caption.

Nimoy died on Feb. 27 at the age of 83 after suffering from chronic obstructive pulmonary disease. At the time of his death, The Big Bang Theory also honored Nimoy in a short Internet post and cast members of the show also took to social media to remember the iconic actor.

Today, we salute the legendary Leonard Nimoy #LiveLongAndProsper https://t.co/nA0tG8C61g pic.twitter.com/7N3NlDX7vf

— The Big Bang Theory (@BigBang_CBS) February 27, 2015

Live long and prosper. #RIP

— Kunal Nayyar (@kunalnayyar) February 28, 2015

From the @bigbang_cbs set. RIP Leonard Nimoy.

A photo posted by mayim bialik (@missmayim) on Feb 27, 2015 at 10:58am PST