Solar System
The Solar System is the gravitationally bound system of the Sun and the objects that orbit it, either directly or indirectly. Of the objects that orbit the Sun directly, the largest are the eight planets, with the remainder being smaller objects, such as the five dwarf planets and small Solar System bodies. Of the objects that orbit the Sun indirectly—the moons—two are larger than the smallest planet, Mercury.
Pythagorean astronomical system
While the earth and planets revolved around a central point in Philolaus's system, his could not be called a Heliocentric "solar system", because the central point the Earth and Planets revolved around was not the Sun, but the so-called Central Fire. This Fire was not visible from the surface of Earth—or at least not from the hemisphere Greece was located in.