TIFF: 'The Martian' Cast Talks About Approach to Astronaut Roles

"You end up like you were a kid in your bedroom pretending that you were in space," Matt Damon told a Toronto festival presser.

Venturing to Mars in Ridley Scott's feel-good sci-fi movie The Martian was like being a child again, Matt Damon and co-stars said Friday at the Toronto Film Festival.

"As big as these movies are, you end up like you were a kid in your bedroom pretending that you were in space. And it works,” the Oscar-winning actor told the press conference for the upcoming Twentieth Century Fox release where he plays an astronaut left for dead on the Red Planet.

Damon pointed to certain tightly-framed shots where, rather than climb into a harness to fly round Mars, he literally assumed the pose of a surfer atop a wave on stage at the TIFF presser to simulate zero-gravity motion. "You're in space, and you act while you're standing on one foot and move slowly, and it's totally ridiculous, but within the confines of that frame, it works," he explained.

Co-star Jessica Chastain said playing an astronaut in The Martian, which has its world premiere in Toronto on Friday night, was like fulfilling a childhood dream. "It's like being a little kid and watching these movies and hoping someday you get to do that. I don't really want to go to space, but I want to pretend to," she told the Toronto media.

Kate Mara, another astronaut in The Martian, also appreciated simulated space travel, yet with her feet firmly planted back on Earth. "I would never make it as an astronaut. But those days were my favorite. It feels very much like a dance, and there's choreography, but once you're doing it, you feel like a kid," she said.

The Martian is set to hit theaters on Oct. 2. Besides Damon, Mara and Chastain, the film stars Jeff Daniels, Michael Pena, Chiwetel Ejiofor, Donald Glover and Sean Bean.