Witherspoon left the role last year due to scheduling conflicts.
She is, however, still on board the project as a producer along with Bruna Papandrea, according to The Hollywood Reporter.
The movie will be directed Noah Hawley from a script by Brian C Brown and Elliott DiGuiseppi.
The film is about a married astronaut who returns to Earth after a mission and begins an affair with a fellow astronaut.
"Pale Blue Dot" will explore the theory that astronauts who spend long periods of time in space begin to lose their sense of reality when they return home.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)