Sahndara was the original star whose system is home of the race that would become the Platonians. Before Sahndara exploded around 400 BCE, 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 moved on to another planet, a class M 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 planets kironide-rich food. (TOS: "Plato's Stepchildren")