MEN IN BLACK    .-     NASA surprised the world on Monday with its announcement that it had found water on Mars. This wasn’t news, though, to the director Ridley Scott, whose latest film, “The Martian,” opens on Friday, and revolves around the struggles of a stranded astronaut and botanist, played by Matt Damon, to survive on the red planet by himself for more than a year.


Mr. Scott said in an interview with The Times on Monday that the head of NASA had shown him the photos of the water about two months ago, and that had the news come out before production of “The Martian” began, it probably would have affected key plot points in the film.

In the movie, which is adapted from a novel by Andy Weir, Mr. Damon’s character makes water by creating humidity and heat and trapping droplets on a plastic tarp, thereby irrigating the potato plants that help him survive. Had the discovery of water on Mars happened before filming began, Mr. Ridley said Mr. Damon’s character “would’ve gone and dug in.”

“He’d’ve found the edge of a glacier, definitely. It would be fascinating,” said the 77-year-old director, who met to chat at the JW Marriott Essex House in Midtown Manhattan. “But then I would’ve lost a great sequence. He has to make water, and the steaming device, and put up the plastic tents, which creates the humidity, which grows the plants, which is the most basic form of irrigation. They still do it in Spain that way.”

Mr. Scott, whose credits include “Alien,” “Blade Runner” and “Thelma and Louise,” said “The Martian” had already screened twice at NASA; it also recently screened for the crew at the International Space Station.

While the discovery of water raises the likelihood of life on Mars, Mr. Ridley added that he has dim hopes for human life on this planet: he doesn’t think people will be around for more than half a century or so.

“I’m not being pessimistic — I think we’ve done it,” he said. “So start getting rifles and find some forest retreat up there.”