Trojan War was reunited with Menelaus. Proteus also told Menelaus that he was destined for Elysium (Heaven) after his death. Menelaus returned to Sparta with Helen eight years after he had left Troy. Agamemnon returned home with Cassandra to Argos. His wife Clytemnestra (Helen's sister) was having an affair with Aegisthus, son of Thyestes, Agamemnon's cousin who had conquered Argos before Agamemnon himself retook it. Possibly out of vengeance for the death of Iphigenia, Clytemnestra plotted with her lover to kill Agamemnon. Cassandra foresaw this murder, and warned Agamemnon, but he disregarded her. He was killed, either at a feast or in
Menelaus of Alexandria great circle arcs, which he named "trilaterals") and proves Menelaus' theorem on collinearity of points on the edges of a triangle (which may have been previously known) and its analog for spherical triangles. It was later translated by the sixteenth century astronomer and mathematician Francesco Maurolico. The lunar crater Menelaus is named after him. The titles of a few books by Menelaus have been preserved: Menelaus of Alexandria Menelaus of Alexandria (; , "Menelaos ho Alexandreus"; c. 70 – 140 CE) was a Greek mathematician and astronomer, the first to recognize geodesics on a curved surface as natural analogs of