A Note on the dating of Beltane May Day
Beltane (or Beltaine or Bealtaine, the Celtic May Day) is a mid-spring seasonal festival that marks a midpoint between Spring Equinox and Summer Solstice, and is celebrated on the eve of May 1st. However, this festival date (like many of these ancient seasonal festivals) is not a precise date on our solar calendar. This has to do with calendrical changes; (a) the change from the Julian calendar to the Gregorian calendar and (b) the Celtic use of a lunisolar calendar. Thus the dates of the festival are different depending on which Celtic country it's celebrated in. For example, Beltane in Scotland was commonly celebrated on the 15th of May, while in Ireland Beltane, or the “Old May,” began about the night of the 11th of May. Before the use of calendars, many Paleo-Celtic peoples celebrated Beltane with the first pinky-white blossoms of the sacred hawthorn tree (also known as “the May"), which blossoms during this month in Ireland and the British Isles.
Again, due to various calendrical changes down through the centuries, the traditional date of Beltane (“Calendar Beltane”) is not the same as its astrological date (“Astrological Beltane"). The astrological date of Beltane is May 4th eve and May 5th, but even this can vary from year to year. Since the Celtic year was based on both lunar and solar cycles, it is possible that the holiday was celebrated on the full moon nearest the midpoint between the Spring Equinox and the Summer Solstice; i.e., the full moon of Taurus as it passes through Scorpio. Again, this date, like all astrologically determined dates, may vary by a day or two depending on the year. However, it may be calculated easily enough by determining the date on which the sun is at 15° Taurus, usually around May 5th. This date has long been considered a “power point” of the Zodiac. Therefore, astrologically calculated, Beltane occurs in the mid-point of Taurus, which technically does not occur until May 5 this year when the Sun reaches 15° degrees Taurus.
In any case, for the GS's purposes, because historically in many locales the celebration of either Beltane or May Day lasted an entire month, the presentation of the musical essays for Beltane/May Day will continue throughout the month of May.