A son of Eos and Tithonos, who was famed for his beauty, Memnon took part in the Trojan War, fighting on the side of the defenders. He met Achilles in combat, and as they were fighting, both the heroes' mothers petitioned Zeus to spare their sons. Zeus, checking the outcome in the golden balance which weighed out life and death, announced that it was Memnon's fate to die at the hands of Achilles. Anxiously, Eos sped to Troy, but found that her son was already dead. She built a great monument to Memnon in Thebes, which, when the first rays of the sun struck it, gave forth a sound like the snapping of a harpstring.