Sahndara was the primary of the Sahndara planetary system. In this system, there was an inhabited planet. The planet, Sahndara, was the homeworld for a warp capable species. Before Sahndara went nova around 400 BC, a group of thirty-eight refugees traveled to Earth where they settled during the time of Plato.
After the time of Plato passed, the settlers, who called themselves Platonians, moved on to another planet which they named Platonius. Here they continued to follow the teachings of Plato, but soon they discovered that they had developed psychokinetic powers, attributed to the planet's kironide-rich food. (TOS: "Plato's Stepchildren")