Telos Major is temperate planet that teeters on the edge of League-controlled space. Some even consider it to be a part of the Galactic Republic. It is the planet from which Carth Onasi originally came from.
It was razed by the Sith Empire before the formation of the Galactic Republic, and it is for this reason that Carth joins the Republic Navy. He eventually becomes Captain of the Endar Spire. It was eventually recomposed by Jorgey shortly after the end of The Rise of Trask Ulgo.
Jorgey's efforts to Compose Telos Major to make it nice again were interrupted by a solar flare that entered the system. Jorgey instead suggested that the planet's yet unterraformed segment by rebuilt as a massive array of solar panels. With help from the Composer, the Telosians constructed the Galaxy's largest solar panel array and used the solar flare activity to create massive amounts of power. It is this array that gives Telos Major its distinctive gray corner.
Telos Major has a twin planet, the ice planet of Telos Minor.