The actor has been invited to join the Blue Origin crew on billionaire Amazon boss Jeff Bezos' next rocket ship mission to the stars and back.
Bezos and his crew have already enjoyed one successful space flight in July (21), and TMZ sources claim 90-year-old Shatner, who played Captain Kirk for years on TV, will be part of the next take-off in the New Shepard capsule on 15 October (21).
If the 15-minute mission goes to plan, the actor will become the oldest person ever to be launched into space.
Insiders claim the space flight will be filmed for a documentary.
Jeff Bezos first flew to space on July 20. He was joined by younger brother Mark among others. His travel to space came roughly a week after Virgin Galactic boss Richard Benson's similar trip.
While Bezos invited William Shatner, Benson initially sold one of the tickets to space to Ashton Kutcher but the former "Punk'd" host gave it up after wife Mila Kunis expressed concerns over his safety.
"My wife basically encouraged that it was not a smart family decision to be heading into space when we have young children," Kutcher revealed. "So, I ended up selling my ticket back to Virgin Galactic. I was supposed to be on the next flight, but I will not be on the next flight."
Meanwhile, Kunis said, "The fact that I didn't let him go into space was so selfish of me, but I was a new mom and I was like, 'You can't leave me and the babies.' And so that's where that decision was made out of."