Although Leonard Nimoy was never physically present on CBS' "The Big Bang Theory" he played such a big role in the show that there was a tribute to him at the end of Thursday night's episode.

Nimoy, who died last Friday at the age of 83, was frequently referenced on the show thanks to Sheldon's (Jim Parsons) obsession with him.

The Star Trek alum inspired the classic children's game used to solve all problems - "Rock, Paper, Scissors... Lizard, Spock."

While Nimoy never actually made an appearance on the show, he did provide his voice during one episode where he was the voice of reason inside of Sheldon's head.

Everyone knew Sheldon was obsessed with Nimoy, and his character Spock on "Star Trek," that his name was frequently mentioned in episodes.

During the show's 100th episode, Penny had Nimoy as a customer while waitressing at The Cheesecake Factory. She managed to get his autograph on his used napkin and gave it to Sheldon for Christmas. He was beyond excited to finally have Nimoy's DNA.

Since Nimoy played such a special role in Sheldon's heart, it only seems right for the show to play a tribute to him after his passing. They did so at the end of Thursday night's episode with a very appropriate picture of Nimoy.