20th Century Fox has released a new featurette for Ad Astra that ties the drama of director James Gray's outer-space epic to the Apollo 11 moon landing, which took place 50 years ago today. Brad Pitt stars in Ad Astra as an astronaut who journeys to the very edge of the solar system to find his missing father (Tommy Lee Jones). Neil Armstrong and Buzz Aldrin starred in the Apollo 11 mission as the actual mad lads who walked on the moon for the first time.

Speaking in the video—which also features footage from the film—Gray explains how that historic moment inspired the sense of exploration in Ad Astra.

“Space travel has really entranced human beings since the beginning. I think the Apollo program was one of the great achievements in all of human history. We’re not really meant to be in space, to be floating around 250 miles outside the atmosphere. But the drive of the human spirit is to explore. ‘Ad Astra’ means ‘to the stars’. The whole line is ‘per aspera ad astra’, which means ‘through hardship to the stars.’ Which I thought was very beautiful."

Check out the video below. Ad Astra—which also stars Liv Tyler, Donald Sutherland, and Ruth Negga—hits theaters on September 20.

Here's the official synopsis for Ad Astra:

Astronaut Roy McBride (Brad Pitt) travels to the outer edges of the solar system to find his missing father and unravel a mystery that threatens the survival of our planet. His journey will uncover secrets that challenge the nature of human existence and our place in the cosmos.

And for even more on the film, make sure to check out the links below:

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