A Betan was the designation given to any Peliar Zel native who lived on the Beta moon of Peliar Zel. Throughout their history, Betans have had numerous wars with Alphans moon and live in a state of perpetual tension with their neighbors.
In 2337, the aunt of Betan Lathal Bine agreed to change places with her Alphan counterpart, Kalin Trose for a week to understand each others situation with more informed eyes.
Thirty years later, Bine found himself in a similar situation when Alpha moon developed a way to tap into the energy from Peliar Zel's magnetic field, causing environmental damage to Beta moon when its orbit passed through the energy beam. That strained reletaions again and both moons started to arm for war. Like his aunt, Bine agreed to mediation by Federation Ambassador Odan, who reminded Bine of the "iron-willed lady of Beta moon" and her willingness to do what was best for her people. (TNG: "The Host")