year was the amount of time it took for a planet to orbit its sun. If the planet had an axial tilt, this resulted in seasons, like winter, spring, summer, and fall.
Vulcan year: In Gene Roddenberry's novelization of The Motion Picture he indicated that nine Vulcan seasons were equal to 2.8 Earth years. This would make Vulcan's year 456 ± 33 Earth days long.
It took the
colony ship SS nine years to get to the Conestoga planet Terra Nova to form the Terra Nova colony in 2078. ( : " ENT ")
Terra Nova Sub-commander T'Pol stated in 2151, that she was not familiar with the early years of Earth space exploration. ( : " ENT ")
Vulcan monastery at P'Jem was almost 3,000 years old as of 2151. According to the Vulcan elder at the monastery, the reliquary wasn't entered in years and the transmitter also hasn't been used for years. ( : " ENT ")
The Andorian Incident
warp three engine, a cargo freighter could cut down a five year cargo run down to six months. ( : " ENT ")
Nausicaan pirates were attacking freighters in a specific sector for years until 2151. ( : " ENT ")
Standard UFP solar year
UFP solar years were mentioned in the Treaty of Armens. ( : " TNG ", The Ensigns of Command )
Earth year was a span of time equal to 365.2425 Earth days.
Captain Jonathan Archer suggested that Bernadette Fuller was around seventy-five Earth years in 2151 while talking to Nadet. ( : " ENT ")
Doctor Phlox, Travis Mayweather was twenty-six Earth years during his autopsy in 2152. ( : " ENT ")
There was a reference to "terrestrial years" in dialogue in the revised final draft script of : " TOS ". In the final version of that episode, however, this reference doesn't include the term "terrestrial". The Conscience of the King