As an aside, Majel was the either the first or science officer on the pilot that ran a year before TOS started. By then the actor who played the captain had a different job so wasn’t available so they found Shatner. Majel had not married Gene yet.
I read somewhere long ago that his wife was opposed to his doing a sci-fi show also.
The strange irony is that Jeffrey Hunter died in May of 1969. The last episode of TOS aired in June of 1969.