‘Twas the night before October 1st. You know what that means! People of all ages are picking out Halloween costumes, skeletons and spider webs are being hung, pumpkins are being carved, and soon enough children will be knocking at your door begging for candy.

Halloween is a widely celebrated holiday, and one of my favorites. But what many people don’t know is the origin of Halloween. The tradition of Halloween originated from the ancient Celtic festival of Samhain. October 31st, the host of Halloween and Samhain, is also the astronomical midpoint between the autumn equinox and the winter solstice.

The Celtics believed that on the night of October 31st, the gates to the Otherworld opened up. This allowed demons, ghosts, and spirits alike to pass over to the side of the living. This is where the idea of dressing up as monsters and ghosts and roaming the streets stems from.

The Celtics relied on astronomy to tell the day of the year, and counted the full moons throughout the year to determine the month. The last month of the Celtic year matched up with the full moon closest to the midpoint between the autumn equinox and the winter solstice, which as mentioned previously, is the month we know as October. During this time of year in the Celts location the nights lasted more and more hours. This placed a relationship between the end of October and darkness and shadows. It is also thought that Samhain occurred on the night the Pleiades star cluster climbed to its highest point. Pagan rituals were practiced as the stars rose to their heights at midnight.

This Halloween week watch out for this cluster in the night sky. To find Pleiades, start by locating the famous constellation Orion. Draw a line upwards using the three stars on Orion’s belt. Follow the line upwards until your eye meets the first bright star, Aldebaran, a part of Taurus. The cluster, a small dipper shaped arrangement, isn’t too much farther past Aldebaran.

So, get your costumes ready and prepare to blend in with the demons walking beside you on All Hallows’ Eve. And prepare any rituals or spells you may have before the rise of Pleiades. Good luck to you on your spooky endeavors, whether it be roaming with the spirits or cursing your ex lover, and may you remember the Celtic and astronomic origin of the tradition you’re partaking in.