Peck, who previously starred in the TV adaptation of the film 10 Things I Hate About You, thanked the family of Leonard Nimoy, who played the half-human, half-Vulcan character in the original Star Trek TV series.

The grandson of Academy Award-winning actor Gregory Peck posted a photo of himself with the late actor's relatives giving the character's trademark Vulcan salute on social media.

Peck wrote: "Thanks to the Nimoy family for your open arms, warm welcome, smiling curiosity and support, for making me feel worthy, as I embrace and take into my heart the iconic half alien we know as Mr Spock. It is an incomparable honour."

Nimoy's television director son Adam also shared the photo, adding: "There's a new Spock in town! Welcome to the family Ethan!!"

Star Trek: Discovery is set before the events of the original series, which also featured William Shatner as the USS Enterprise's Captain James T Kirk.

In the new series, Spock is still the chief science officer under the Discovery spacecraft's captain Christopher Pike (Anson Mount).

Star Trek: Discovery showrunner Alex Kurtzman told the Hollywood Reporter: "Through 52 years of television and film, a parallel universe and a mirror universe, Mr Spock remains the only member of the original bridge crew to span every era of Star Trek.

"The great Leonard Nimoy, then the brilliant Zachary Quinto, brought incomparable humanity to a character forever torn between logic and emotion.

"We searched for months for an actor who would, like them, bring his own interpretation to the role. An actor who would, like them, effortlessly embody Spock's greatest qualities, beyond obvious logic: empathy, intuition, compassion, confusion and yearning.

"Ethan Peck walked into the room inhabiting all of these qualities, aware of his daunting responsibility to Leonard, Zack and the fans, and ready to confront the challenge in the service of protecting and expanding on Spock's legacy. In that spirit, we're thrilled to welcome him to the family."

Nimoy died on February 27 2015 at the age of 83.

Australian Associated Press