Pitt was sporting a fresh 'do, looking dapper in an emerald green dress shirt and tie.
"He's very affable," a source tells ET, noting that Pitt's six children -- Maddox, 16, Pax, 13, Zahara, 12, Shiloh, 11, and 9-year-old twins Knox and Vivienne -- have not yet visited the set. "He comes to work in a good mood."
"He's a movie star in the best way," the source adds. "Prepared, on time, friendly. All the things you want a person to be… he is that. He's always ready to work."
The James Gray-directed film follows the story of Roy McBride (Pitt), an Army Corps engineer who goes on a journey across the galaxy in search of his father, a renegade scientist who went missing in space 20 years ago. The sci-fi thriller also stars Ruth Negga, Tommy Lee Jones, Donald Sutherland and Jamie Kennedy.
Earlier this month, an additional source told ET that although they're not planning to get back together, Pitt and Jolie have slowed down their divorce process.
"There's a pause in the [divorce] process because they both made children the priority, but nothing significant has changed in their relationship," the source explained. "Both have demonstrated great civility recently for their kids."
Hear the latest on the former couple in the video below.