10:00 pm EDT on October 16, 2008. Looking at Zenith, South at Bottom. (click to enlarge)*
Many of the constellations of autumn owe their origins to a comprehensive theme of Greek mythology. Cepheus and Cassiopeia were rulers of ancient Ethiopia. The queen was so proud of their beautiful daughter Andromeda that she put forth the young woman as more lovely than the sea nymphs in the court of Poseidon, the Sea God. Poseidon, in order to appease his outraged retinue, sent the sea monster Cetus to ravage the coast of the kingdom. Cepheus, in what must have been the mother of all no-win situations, chained Andromeda to a rock as a sacrifice to Cetus in the hopes of getting cut some slack. Enter the hero, Perseus riding his (winged, naturally) horse, Pegasus, fresh from the decapitation of the horrible witch Medusa, whose very aspect would turn men to stone. (Perseus managed to find and slay Medusa by looking at her reflection only in his shield.) Perseus pulled Medusa's head from his bag and managed to petrify the sea monster, free the princess, and save the kingdom. Film at 11.

Pegasus is at the epicenter of a cluster of autumn constellations based upon this myth. The "square" of four 2nd-magnitude stars at its center can be used as a guide: a line from Algenib, in the SE corner, through Alpheratz, in the NE corner, points to Cassiopeia. A line in the opposite direction points to Cetus. A diagonal line from Markab, in the SW corner, through Alpheratz points to Perseus. A line from Markhab through Scheat, in the N corner, ultimately leads to Cepheus. With the evidence of the whole story laid out so prominently across the sky, who needs CSI?