United Kingdom, May 22 -- William Shatner almost got off the Blue Origin rocket during the countdown to his historic space flight.

The 95-year-old actor became the oldest person to go up into space when he blasted off on Jeff Bezos' New Shepard NS-18 rocket in October 2021 but he had doubts while climing 11 stories in the gantry to get to the ship opening and noticed gas coming off one of the vents, which he was tod was hydrogen.

Speaking in conversation with close friend Neil DeGrasse Tyson during their The Universe Is Absurd! event at the Saban Theatre in Beverly Hills, the Hollywood Reporter reports he added: "So now, with trepidation, I enter the ship and I'm in the chair, a five-point buckle, and the countdown begins."

To add to h...