TORONTO -- "Star Trek" icon George Takei is both celebratory and sombre as he reflects on the 50th anniversary of the sci-fi franchise, a milestone that was "absolutely undreamed of" when the Starship Enterprise first took flight.

"We had the Vulcan greeting: 'Live long and prosper.' Well, we've certainly lived much longer than anyone has expected, and we've prospered in so many, many wonderful ways," Takei said in a recent interview from Los Angeles.

"The gift has been this fan following and undying support that has us travelling all over the world to celebrate the show and its franchise."

Takei said the "other poignance" of the 50th anniversary is remembering those who didn't live to see the milestone, including series creator Gene Roddenberry, and co-stars Leonard Nimoy (Spock), DeForest Kelley (Dr. Leonard "Bones" McCoy) and Vancouver-born James Doohan (Scotty).

"We've lost so many of our colleagues who've become friends," said Takei.

"It's a time of celebration, but it's also a time of reflecting on the mortality of everything and to appreciate what they have left us with."

A pall was once again cast over the franchise with news of the accidental death of 27-year-old Anton Yelchin, who portrayed Chekov in the rebooted film series.

An autopsy performed on the late actor determined he died of blunt force asphyxia after his Jeep pinned him between a mailbox and a security pillar in his driveway.

Takei offered condolences to Yelchin's family and friends in an online tribute. "Our 'Star Trek' family has lost one of its own," he wrote on his Facebook page.

Takei, 79, is best known for his portrayal of Hikaru Sulu on the 1966 TV series and the first six feature films, and has kept busy with appearances at events frequented by loyal Trekkies.

The California native recently returned from a "Star Trek" convention in Bonn, Germany, which was also attended by Canadian co-star William Shatner (Capt. James T. Kirk) and Walter Koenig (Chekov). Takei is also slated to appear at the official "Star Trek" 50th anniversary convention in Las Vegas in August, and Fan Expo Canada in Toronto in September.

Takei has also kept plenty busy with his other passion projects, including his vocal advocacy for LGBTQ rights. He will be a part of Pride Toronto festivities with "An Evening with George Takei," a lecture and Q&A session at Ryerson Theatre on Sunday.

And he's eked out a sizable niche on social media with his eclectic mix of posts, racking up more than nine million likes on Facebook and more than 2.5 million followers on Twitter and Instagram.

While Takei takes a largely light-hearted approach to his social media strategy, the origins stemmed from seeking to highlight a grim chapter of American history.

In 2008, he began development on a musical about the internment of Japanese-Americans during the Second World War. Takei saw social media as a key tool to help spread the word.

"At that time, my audience base was essentially sci-fi geeks and nerds, more specifically 'Star Trek' fans -- and I had to grow that," said Takei.

"By trial and error, I found that humour was the key to getting more likes and shares. And because it's a sharing medium, we got people sharing their memes with us, and so I just reshared them."

The strategy paid off with "Allegiance" enjoying a Broadway run and possible adaptation into a feature film.

And what's left to accomplish on the septuagenarian's to-do list? Taking a second run at sharing his life story, which was first published in 1994.

"(The story) ended in '91, and I've lived a lot of material, so I'm pecking away at that."