“As soon as I learned what the moon was, I learned that somebody named Neil Armstrong walked on it,” Gosling, 37, tells PEOPLE.
While preparing for the role, the actor says he was surprised to learn how dangerous the mission was.
“I had no idea how claustrophobic and frail those space capsules were,” he says. “We have more computing power in our cell phones than they had on those early spacecraft.”
For more on Gosling, pick up this week’s issue of PEOPLE on newsstands now.
The drama, which also details Armstrong’s relationship with his wife, Janet (Claire Foy), and the tragic death of their daughter, reunites Gosling with his La La Land director, Damien Chazelle.
“I can’t imagine a greater duality than that between the intimacy of the Armstrongs’ personal life and the infinite nature of space,” Gosling says.
As for the pressure of portraying an American hero? He jokes he’s fine—”as long as people don’t find out that I’m Canadian.”
First Man also stars Kyle Chandler, Jason Clarke, Patrick Fugit, Christopher Abbott, Ciaran Hinds, Ethan Embry, Shea Whigham, Corey Stoll and Pablo Schreiber.
It opens in theaters Oct. 12.