The Sky This Week, 2011 April 26 – May 3 — Naval Oceanography Portal

May 1st is one of the ancient seasonal markers that were once widely observed throughout Celtic and medieval Europe. Now widely observed as "May Day", an international workers’ holiday, its origins date back well over a thousand years. Celtic societies knew it as "Beltaine" a celebration of the opening of the agricultural planting and breeding season and the end of boreal winter. It was celebrated by huge bonfires and much merry-making, with attendant May-poles, May Queens, and general "mayhem". May Day is one of the so-called "cross-quarter" days that mark the mid-points of the astronomical seasons. The four seasonal markers and four cross-quarter days were the traditional dates when serfs paid their rent to their feudal masters in medieval times. We still unwittingly observe three of the four cross-quarter days in modern times. In addition to May Day, the old Celtic observance of Samhain is now celebrated as Halloween, and Imbolc is now observed as the Christian Candlemas or secular Groundhog Day. The fourth cross-quarter day, Lughnasadh, falls on August 1st, and is still observed in a few locations in Scotland as "Lammas". Whatever the origins, May Day is still a time to celebrate the rebirth of spring as new leaves green the trees and new life emerges in field and forest.

The Sky This Week, 2011 April 26 – May 3 — Naval Oceanography Portal