The Discovery of a Second Lunar Calendar on Rongorongo Tablet C (Mamari)

This paper identifies and analyzes a previously unrecognized lunar calendar on the recto of Rongorongo Tablet C (Mamari). By applying a structural analysis to recurring delimiter sequences and "staff and bud" glyphs, the author demonstrates a second calendrical pattern (Lunar Calendar B) that aligns with the known lunar calendar identified by Thomas Barthel (Lunar Calendar A). The study compares the sequence of 29 "buds" in the new calendar with the 31 "nights" in the traditional calendar, proposing that the system may represent an agricultural cycle or an alternating 29/30-day lunar month used by the Rapanui people.