Pacifica was an ocean planet and Federation Member State in the Taurus Reach region, in the Alpha Quadrant. It was the homeworld of the Selkie species and the location of a Federation colony. (ST reference: Star Charts; TTN novel: Orion's Hounds; VAN novel: Reap the Whirlwind)
Pacifica was famed for its warm blue waters and fine beaches, considered to be a "jewel in the galaxy", and making it a popular tourist destination. Other attractions on Pacifica, include the vast underwater city of hi'Leyi'a. (TNG episode: "Conspiracy"; TTN novel: Taking Wing)
In early 2268, Cervantes Quinn had heard about some easy-money jobs hauling gray-market cargo to Pacifica. Quinn also wanted to spend some time on Pacifica for a tropical vacation. (VAN - Declassified novella: The Stars Look Down)
In 2269, USS Enterprise archeologist Lieutenant O'Hara left the ship to raise a child on Pacifica, one which contained DNA from her diseased brother Matthew O'Hara. She also looked forward to exploring the ruins on the surface. (TOS - Year Four comic: "Issue 6")
In 2310, Captain John Harriman and Amina Sasine vacationed on Pacifica, in the city of Jannita where they danced throughout the night. (TLE novel: Serpents Among the Ruins, TLE novel: One Constant Star)
In the early 24th century Pacifica was the subject of an oceanographic study headed by Doctor Gillian Taylor. The project was based on a drift-station (dubbed Madrigal) located on the ocean surface. Among the project members was a humpback whale named Harpo.
Circa 2310, Pacifica was selected as a testbed for a modified Genesis Device created by Dr. Carol Marcus. These tests were halted when a race of sentient beings were discovered hidden in the depths of the ocean. (TOS short story: "The Hero of My Own Life")
- This would seem to be contradicted by the information from Reap the Whirlwind and Serpents Among the Ruins, as such a test would not have been considered on an established, inhabited colony world. It may also be inconsistent with the Selkie species established in the Titan series; In "Hero of My Own Life" the inhabitants of Pacifica are established as non-natives who had been kidnapped from their homeworld by Orion slavers in the early 22nd century, and escaped to an uninhabited planet.
In 2364, the USS Enterprise-D was scheduled to conduct a scientific mission on Pacifica, but was diverted to Dytallix B before the start of the mission. A year later, the Enterprise ferried two Antedean dignitaries to Pacifica when the planet was hosting a conference to discuss the admission of the Antedeans into the Federation. (TNG episodes: "Conspiracy", "Manhunt")
Following the Raid on San Francisco by the Breen during the Dominion War and the broadcast of images of the damaged Golden Gate Bridge, applications to join Starfleet from Pacifica increased. (ST - Typhon Pact novel: Rough Beasts of Empire)
In 2376, Carol Abramowitz spent part of her leave time on Pacifica, following her mission to Vrinda. (SCE eBooks: Age of Unreason, Breakdowns) Also in 2376, a Council of Governors meeting was held on Pacifica; Nanietta Bacco had been in attendance and met Admiral William Ross, who was the guest speaker. (TNG novel: A Time for War, A Time for Peace)
During the Borg Invasion of 2381, numerous evacuation ships from around the Federation fled for Pacifica, including one from Cestus III carrying the family of Miranda Kadohata. (ST - Destiny novel: Mere Mortals) Several thousand evacuees who had lost their homes were forced to take refuge on Pacifica, many of them on the island of iy'Dewra'ni. (TNG novel: Losing the Peace)