While they were no big deal a decade or more ago, positive references to Christianity in movies have become increasingly rare. Films can include characters expressing strong belief and support for any number of political views and sexual proclivities, but mentioning Christ’s name as anything but an epithet is a vanishing phenomenon.

Nearly the last place one might expect to see this happen is in a science fiction film, especially one directed by self-proclaimed atheist Ridley Scott. But since Drew Goddard wrote the script, it’s a little less mysterious. More on this in a bit.

On Tuesday, Aug. 18, journalists descended on a theater in La Ca√±ada Flintridge for a partial screening of “The Martian,” due out from 20th Century Fox on Oct. 2. Matt Damon stars as NASA astronaut/botanist Mark Watney, who is left for dead when the crew of a Mars mission must hastily abort and lift off to escape a fierce storm.

But Watney is not dead. Alone on the Red Planet — armed with equipment, knowledge, disco music and a snarky wit — he faces the challenge of keeping himself alive until his colleagues concoct a way to save him.

On hand to answer questions after a screening of 49 minutes of the unfinished film were Damon, Scott, NASA space physicist Dr. Jim Green, NASA astronaut Drew J. Fuestel and Andy Weir, a computer-programmer-turned-author who wrote the book that inspired the movie.

August marked the third anniversary of NASA’s successful landing of the Mars rover Curiosity, the latest in a series of robotic vehicles exploring the planet in advance of a manned mission, currently targeted for the 2030s. Unlike space fantasies like “Star Wars” or “Guardians of the Galaxy,” “The Martian” tries to stay as close as possible to scientific reality, or at least the near-future extrapolation of it.

Scott was a fan of the 1983 movie “The Right Stuff,” which told the fact-based story of the original Mercury 7 astronauts.

“It’s fundamentally about how astronauts have to deal with fear, terror and, ‘Oh, my God, I’m going to die,’” he said. “They deal with it with control and coolness, to make it simplistic. In essence, this film is about a guy who controls all those feelings about what a terrible situation he’s in and where he is, and therefore will look for that internally, inside himself, and pull out the elements that might make things humorous.”

That aspect also attracted Damon, but despite the number of space films he’s done, he made it very clear it’s just playing pretend.

“I’m an actor,” he said. “The astronauts are very selfless; they’re thinking of the bigger project. The actors just want to look at themselves, totally different animal.”

But he does think “The Martian” can do some good.

“I don’t have any lofty expectations,” he said, “but I do hope that some kids see it and geek out on science and enjoy it.”

Now, back to Christ.

In one scene, Watney needs to burn something, but fire-averse NASA insists that everything be flame-retardant. So, Watney turns to the only flammable material he can find — a wooden crucifix left behind by fellow astronaut Martinez (Michael Pe√±a).

Watney carefully carves a few slivers off the bottom of it. Then, lying in his bunk, he looks at Christ on the cross and says (according to my notes), “I figuring you’re OK with this, considering my circumstances. Countin’ on ya.”

After the screening, roundtable interviews with Feustel, Green and Weir took place at nearby Jet Propulsion Laboratory, a NASA/CalTech facility where Mars rovers are designed and built.

Asked about the crucifix, Weir said, “In the movie, that’s the only reference to Martinez’ religion. In the book, there are a few other times where he’s praying. … He’s supposed to be a devout Catholic.”

In the same scene in an ebook version of the novel, Watney chips the whole crucifix into splinters and says, “I figure if there’s a God, he won’t mind, considering the situation I’m in.”

Why the subtle shift to a more respectful line hinting that Watney is a believer? Might be because Goddard — creator of Netflix’s “Marvel’s Daredevil,” about Catholic superhero Matt Murdock — was raised Catholic in Los Alamos, New Mexico.