Lunar Cycles & The Lords Of The Night

The Lunar Series was the first Maya original contribution to the calendar and was incorporated early in the 3rd century AD. It was displayed just after the long count and tzolk'in in a sequence of four to eight glyphs. Using lunar day counts of 29 or 30 days, the Maya grouped Moon cycles into sets of six lunations (a lunation being the time between two, successive new Moons).

Also within, or at least connected to the Lunar Series is a 9-day cycle called the Lords of the Night. Little is known about the significance or origin of this 9-day cycle, but it is recognized as the smallest cycle the Maya recorded. An interesting modern Maya use of nine days is connected to the Tzolk'in and the day of one's birth. In Maya communities of the Guatemalan highlands, it is said that counting nine days forward and nine days backwards from one's tzolk'in birthday gives the identities of their protector nawals, or protector spirits. Together, scholars refer to the Lords of the Night and the Lunar Series collectively as the Supplemental Series.

In each of the over 250 known inscriptions containing a Lunar Series, a few standard points of information are provided. Those are; how many days have passed during the current lunation, which of the cycles of six lunations this Moon is in, the name of the current Moon, and how many total days this lunation has (29 or 30). Individually, the glyphs representing these points of information were labeled by Morley as glyphs A, B, X, C, D, E, F and G. Glyphs Y and Z were added as reading methods became more refined. Rarely does a single text display all of these glyphs, usually conflating them into pairs or omitting a few for textual space considerations.

The earliest known Lunar Series from the Maya world comes from an object called the Leiden Plaque, an eight inch jade celt meant to hang from the waste of a royal costume. On its front side a king is displayed, standing atop a captive and wearing an elaborate costume. The date etched on its back side is 8.14.3.1.12 1 Eb 0 Yaxkin, or September 17th, 320 AD. At the very bottom of the text, after the long count and the tzolk'in day, a group of eight smaller glyphs provide first the Lord of the Night and then some basic Lunar Series data. Though stylistically this artifact can be tied to the Peten, it was looted from its original context, so its exact point of origin remains unknown. The earliest known Lunar Series from a stela with secure archaeological context comes from Uaxactun and dates to 357 AD (Mayan-Calendar)