For countless centuries, the Full Moon had great importance. One reason was the lack of artificial lights, which made travel perilous unless a bright Moon was out. Moonlight mattered until the 19th century. Now, few of those festivals and lunar calendars still remain. But one of them unfolds with last weekend’s Full Moon.
Passover and Easter’s changing dates start out simple enough. Easter is the Sunday following the first Full Moon on or after the spring equinox, and that’s this Sunday.
The earliest possible Easter would thus be produced if a Full Moon landed on the equinox, and if that was a Saturday. Then Easter would be the next day, March 22.
It’s pretty unlikely, and equally improbable is the latest possible Easter, which paradoxically arises if the Full Moon lands one day sooner — March 20, which, by the rules, forces us to the next Full Moon on April 18. Then, if that happens to be a Sunday, we must wait a week for the ensuing Sunday, bringing Easter to April 25. So a quick hint is that if there’s a Full Moon in the week after the spring equinox, that year will see an early Easter. I hope you’re writing all this down.
Passover is celebrated on the very day of that first post-equinox Full Moon. Since that Full Moon happened last Saturday, April 12, Passover as well as Palm Sunday were last weekend. A quick consequence of all this is that you’ll see a Full Moon every Passover, and a third-quarter Moon, meaning a Half Moon lit up on its left side, shining in the morning daytime sky every Easter. Go out this Sunday morning and you’ll see it. Throw in a few more ethnic holidays, and you’ve got the vestigial legacy of the Moon’s once far-reaching influence.
Despite the various Full Moon’s central role in these major religious festivities, our ancestors gave them no specific names, with the sole exception of Native Americans. Yet suddenly, starting around 20 years ago, some science writers and major media announcers began announcing that a particular Full Moon (say, last Saturday’s, on April 12) was “The Pink Moon,” as if that name had any actual, official, dictionary or astronomical legitimacy or usage. In reality, only the Algonquin tribe, and a minority of Colonists following their lead, referred to April’s Full Moon a “Pink Moon.” Most colonists called it the Planters Moon or Easter Moon while the Cheyenne called it the Spring Moon. Other Native Americans had a dozen other terms for it. For astronomers the world over, only a pair of autumn Full Moons have actual names (Harvest Moon and Hunters Moon), and these are based on actual, unique lunar behavior at that time of year.
In short, those “Pink Moon,” “Wolf Moon,” “Strawberry Moon,” and similar pronouncements in the media are recent phenomena with little or no legitimacy. Nonetheless, if it’s clear this Sunday morning, check out the nameless last-quarter Moon — the half Moon responsible for making it Easter.
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