Ceti Alpha V
The rugged Class-M world is where Captain Kirk leaves Khan Noonien Singh, former Lieutenant Marla McGivers and Khan's band of Eugenics War-era "supermen" survivors from the Botany Bay to fend for themselves as punishment for their attempted commandeering of the Enterprise in 2366, rather than be placed in a standard penal colony.
The planet became a barely habitable sandscape when neighboring Planet Ceti Alpha VI became unstable and exploded. In 2385, Khan took advantage of a U.S.S. Reliant landing party and used it to attack Kirk's Enterprise once again.
In a 22nd century timeline subsequently erased by the successful removal of multiphasic parasites from the brain of Captain Archer, Ceti Alpha V was the last gathering point for straggling human survivors after the Xindi wiped out Earth and all its major colonies in 2163.