Trinary star system

A trinary star system, also called a ternary system, trinary system, ternary star, trinary star, or trinary sun, was a star system made up of three stars.

In 2152, radiation from a trinary star system caused the crew of Enterprise NX-01 to obsess over insignificant details and tasks. Continued exposure eventually resulted in unconsciousness, and death would have followed had the ship not moved out of range. The radiation itself apparently had no lasting side effects. (ENT: "Singularity")

After being abducted to the planet Triskelion in 2268, Captain James T. Kirk took note of the trinary suns. Later, when Uhura wondered if the USS Enterprise would be able to find them, stating, "We're here, and we don't know where it is," Kirk assured her that "this system's star is a trinary. Limits it a bit, but we're a long way from the Enterprise, if we're in the same dimension." Kirk later explained to Shahna, that "From Earth, Triskelion's three suns are just a flicker of light." (TOS: "The Gamesters of Triskelion")

According to Kor, during Kang's battle against T'nag, "Kang took the high ground and, keeping the three suns to his back, he forced the enemy to fight him against the blinding light." (DS9: "The Sword of Kahless")

In 2372, Jadzia Dax asked for Captain Benjamin Sisko's permission to send a science team to investigate a trinary star system. Sisko told her the team could take the USS Rubicon. (DS9: "Accession")

In 2373, Commander Chakotay ordered Ensign Harry Kim to mark the coordinates of a trinary star in the Delta Quadrant, as he thought it would make "a good point of reference" for the sector the USS Voyager was passing through. (VOY: "Favorite Son")

When the Terrellian Irina told Harry Kim in 2377 that she was from "a small trinary system," he joked, "Three suns? Must make for some long days." (VOY: "Drive")