LOS ANGELES — “Faster alone, further together,” Brad Pitt murmured. Over his left shoulder hung Mars, reddish-brown and heartbreakingly small, while to his right, the much grander Jupiter was lit up like a disco ball.

We were seated opposite each other on the lowest level of the Griffith Observatory in Los Angeles, inhabiting a closed-off exhibition called “Depths of Space,” mulling stoic men. Pitt has played his fair share of them in the movies, including two characters just this year: Cliff Booth, the stunt man who sauntered through the summer hit “Once Upon a Time … in Hollywood,” and Roy McBride, an astronaut shuttled to lonelier, ever more remote outposts of the galaxy in the coming “Ad Astra.”

Movie stars have their specialties, and while Pitt has proved that he can play a motormouth in films like “12 Monkeys” and “Snatch,” he’s at his most alluring when he’s holding something in reserve. It feels like you’re watching a man who says no more than he needs to, which is a major feat for someone who has starred in two films from the notoriously loquacious Quentin Tarantino.

“I grew up with that be-capable, be-strong, don’t-show-weakness thing,” Pitt told me. He was raised in Springfield, Mo., the eldest of three children, his father the owner of a trucking company. Now, at 55, he’s reached a point where he sees his dad in every performance he gives. “In some ways, I’m copying him,” Pitt said. “He had grown up in extreme hardship and poverty, always dead set on giving me a better life than he had — and he did it. But he came from that stoic ilk.”