Mairin ni Bhroanin was a female human of Irish descent who served in Starfleet in the 24th century. She served aboard the USS Gettysburg in 2323, and had befriended Ensigns David Gold and Augustus Bradford when they were assigned to that ship that year.

In 2328, Lieutenant ni Bhroanin was a member of an assault team assigned to capture a secret Cardassian surveillance post hidden beneath the surface of the moon of Delavi III. She was one of five survivors, along with Gold, Bradford, and Ensigns Jolev and Rha-Teramaet. The five would remain fast friends for the remainder of their careers. (CoE eBook: Turn the Page)

By the early 2370s, ni Bhroanin had risen to the rank of Captain, and had been given command of the USS Huygens. She was killed in an engagement with the Klingons during the rift between the Klingon Empire and Federation in 2372-2373. Her death hit Gold hard, and led him to consider retirement from Starfleet. (SCE eBook: War Stories, Book 2)

USS Gettysburg personnel
	A. Bradford • D. Gold • Mairin ni Bhroanin • M. Jameson • Jolev • Rha-Teramaet • Dilat th'Sena • T'Vel