fl. first century A.D.

Greek astronomer whose On the Circular Motions of the Celestial Bodies provides valuable information regarding the work of his more distinguished predecessors. On the Circular Motions is made up almost entirely of ideas taken from others, most notably Posidonius (135-51 B.C.), and contains a mixture of accurate and wildly inaccurate data. Of particular interest is the fact that the text serves as the principal source regarding the methodology used by Eratosthenes (c. 285-c. 205 B.C.) in making his famous measurement of Earth's circumference.