Starfleet

Starfleet is a fictional organization in the Star Trek media franchise. Within this fictional universe, Starfleet is a service maintained by the United Federation of Planets ("the Federation") as the principal means for conducting deep-space exploration, research, defense, peacekeeping, and diplomacy. While the majority of Starfleet's members are human and it is headquartered on Earth, hundreds of other species are also represented, including the majority of the franchise's protagonists.

During production of early episodes of the original series, several details of the makeup of the Star Trek universe had yet to be worked out, including the operating authority for the USS Enterprise. The terms Star Service ("The Conscience of the King"), Spacefleet Command ("The Squire of Gothos"), United Earth Space Probe Agency ("Charlie X" and "Tomorrow Is Yesterday"), and Space Central ("Miri") were all used to refer to the Enterprise's operating authority, before the term "Starfleet" became widespread from the episode "Court Martial" onwards.

However, references to the United Earth Space Probe Agency, and its abbreviation UESPA, are to be found in episodes of later series. For example, the Friendship One probe (launched, on the fictional timeline, in 2067) is marked with the letters UESPA-1 in the Star Trek: Voyager episode "Friendship One". Other background props included additional UESPA references, such as Captain Jean-Luc Picard's family album in Star Trek Generations. During the production of Star Trek: Enterprise, some larger Starfleet insignia designs included the name "United Earth Space Probe Agency".

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