Oh, Halloween. What a fun holiday! Kids, costumes and candy. Spooky-scary fun for all!
I know some folks get uptight about this Holiday, relating it to Devil Worship, for the narrow-minded or at best, Paganism. Pfft. Its an astronomical holiday! Sure, it relates back to the festival of Samhain in Celt and Druidic culture. If you think about it, many of our holidays or customs relate back to such festivals and traditions. Heck the date of Christmas itself probably relates back to Saturnalia. Jesus wasn't born on December 25th.
Most holidays, when you think about it are astronomical in origin, as they related to the Solstices or other astronomical movements. Without "America's Got Talent", "Dancing with the Stars" and Daily (Bad) News Broadcasts, folks spent much more time watching the sky than most of us.
Building tales around the movement and stories of the objects in the sky was a thing in those days. As I understand one story behind the Pleiades is that they were seven sisters. One day the Hunter Orion noticed them and drunk with lust pursued them across the countryside for 7 years. Eventually Zeus took pity on them, transforming them into doves and nestling them safely in the sky out of Orion's grasp.
Halloween is the night that the ghostly blue sisters culminate to their highest point in the sky, at midnight.
Wishing you and yours a safe and fun Halloween!