Admiral Cornwell says that the Discovery will be the first Federation ship in nearly one hundred years to visit Qo'noS, since Captain Archer and the Enterprise visited the Klingon home world in 2151 in Broken Bow, Part 1 (2001).
Commander Spock was born on January 6, 2230 in the city of Shi'Kahr on the planet Vulcan. He would be around 27 years old at this time.
Prime Timeline:
Star Trek: Enterprise (2001) (2151-2161)
Star Trek: Discovery (2017) (2255)
Star Trek (1966) (2265-2269)
Star Trek: The Animated Series (1973) (2269-2270)
Original Star Trek movies (2273-2293)
Star Trek: The Next Generation (1987) (2364-2370)
Star Trek: Deep Space Nine (1993) (2369-2375)
Star Trek: Voyager (1995) (2371-2378)
This episode takes place in 2257.
47 reference: when the computer is reporting the spore production percentage.