My dad was — and is — a huge Star Trek nerd, and when I was a kid he'd excitedly show me episodes of the original series in syndication. It was a show that he watched in college, he'd say, explaining why Kirk was Kirk, Bones was Bones, and most importantly, why Leonard Nimoy's Spock was Spock. One of my earliest moments of geek fandom was when I tracked down the script for the original Star Trek pilot, "The Cage." I got it, read it, and excitedly took it to my dad. Kirk wasn't even in it, I explained to him. Spock had these crazy emotions!

My dad knew, of course. He was a Star Trek geek after all.

It was his voice. Instant gravitas.

Nimoy was there too, when I sat down cross-legged on our living room carpet to watch episodes of In Search Of. The show was a kind of Cosmos for crazy murders and conspiracy theories, and with Nimoy narrating, I loved it. It was his voice: Calm. Commanding. Instant gravitas, but never off-putting. It was the kind of warm, almost paternal presence that invited you into a story, telling you This is important, and you will want to see what happens.

Then came Star Trek II: The Wrath of Khan. For my money, it's easily the best of the Star Trek films, and when Spock died, I was devastated. I've cried far too many times over his final scene in that film — to this day it still pushes those buttons — but that's what Nimoy brought to his portrayal of Spock. A character that was not only the most stoic of the stoic, but paradoxically, the most human of the human.

Nimoy helped me understand how movies were made

Nimoy stepped into the director's chair for the next two installments in the franchise, and I still remember how the young me was amazed that somebody could both act and direct a movie. I was eight when The Search for Spock came out, and it was the turning point when I understood that the movies weren't just something magical that I went to with my dad every weekend; they were things that were made. It was a revelation that would basically dictate my interests and the direction of my life from that day forward.

And as I grew up, Leonard Nimoy continued to be that comforting presence. Whenever he showed up in anything — yes, even Fringe — the movie or show became instantly grounded. Safe. His presence simply meant that I was going to enjoy what I was watching more than I had before. There aren't many actors that do that; he was one. (There's a reason he's been the best thing about J.J. Abrams' Star Trek films, after all.)

And now he's gone.

It's really strange to type that, and while I can't say I ever had the pleasure of meeting or interviewing Nimoy, he's nevertheless felt like a continual presence in my life. That can happen with media personalities, of course. You see somebody on the television every day, and you begin to think you know them; you follow the ups and downs of a fictional character, and you become emotionally bonded to them. Nimoy was something slightly different, though. A star in the media constellation that remained forever constant; true north.

A star in the media constellation that remained forever constant

Of course, it should go without saying that the sense of someone we get from their acting and public appearances often bears little resemblance to who they actually are. But what is undeniable is the emotional impact their work has on us. And for the millions of people, like myself, that grew up with Leonard Nimoy, those are the memories that we will carry with us throughout our lives.

It's a sentiment that Nimoy himself reflected upon on Twitter this past Sunday, in his very last post. "A life is like a garden," he wrote. "Perfect moments can be had, but not preserved, except in memory."

That's what we'll have to do, then.