100 Greatest Discoveries - Astronomy

"Ποταμοῖς τοῖς αὐτοῖς ἐμβαίνομέν τε καὶ οὐκ ἐμβαίνομεν, εἶμέν τε καὶ οὐκ εἶμεν."

"We both step and do not step in the same rivers. We are and are not."
Heraclitus the Riddler