From Battlestar Wiki, the free, open content Battlestar Galactica encyclopedia and episode guide
Planet Starbuck is a barren, desert-like planet that its sole Colonial occupant, Starbuck, names after himself.
During the battle above this planet, both Lieutenant Boomer and Starbuck engage a squadron on Cylon Raiders. With Starbuck's Viper too damaged to make it back to the Fleet, Starbuck makes a one-way trip to the planet and begins to grow lonely on planet.
Eventually, he discovers a Raider he had shot down also crash-landed on the planet, using the debris from the Raider to build a shelter, as well as eventually rebuilding a lone Centurion whom he calls Cy (The Return of Starbuck).