The Rapa Nui calendar was the indigenous

lunisolar calendar A lunisolar calendar is a calendar in many cultures, combining lunar calendars and solar calendars. The date of Lunisolar calendars therefore indicates both the Moon phase and the time of the solar year, that is the position of the Sun in the ...

Easter Island Easter Island ( rap, Rapa Nui; es, Isla de Pascua) is an island and special territory of Chile in the southeastern Pacific Ocean, at the southeasternmost point of the Polynesian Triangle in Oceania. The island is most famous for its ne ...

. It is now obsolete.

Attestation

William J. Thomson, paymaster on the USS ''Mohican'', spent twelve days on Easter Island from December 19 to 30, 1886. Among the data Thomson collected were the names of the nights of the

lunar month In lunar calendars, a lunar month is the time between two successive syzygies of the same type: new moons or full moons. The precise definition varies, especially for the beginning of the month. Variations In Shona, Middle Eastern, and Eur ...

and of the months of the year: :''The natives reckoned their time, and in fact do so still by moons or months, commencing the year with August, which was, according to the traditions,the time when Hotu-Matua and his followers landed upon the island.''

Months

Thomson recorded the months as follows: :

Days

The month was divided in two, beginning with the new and full moon. Thomson recorded the calendar at the time of his visit to the island as follows. The new moon occurred on November 25 and again on the night of December 24; Thompson records the crescent was first visible on November 26. : The three sources we have correspond with each other except for two intercalary days (in bold), and the night of the new moon in Englert, which seems to have been confused with one of these. Beginning with ''(o)ata,'' the night of the new moon, they are: :*New moon, full moon, and first and last quarters. The ''kokore'' are unnamed (though numbered) nights; ''tahi, rua, toru, haa, rima, ono'' are the numerals 1–6. The word is cognate with Hawaiian ''‘a‘ole'' "no" and Maori ''kahore'' "no" and Tahitian ''‘aore'' "there is/are not"; here it may mean "without name nameless

Analysis

The calendar collected by Thomson is notable in that it contains thirteen months. All other authors mention only twelve, and Métraux and Barthel find fault with Thomson: :''Thomson translates Anakena as August and suggests that the year began at that time because Hotu-Matua landed at Anakena in that month, but my informants and Roussel (1869) give Anakena as July.'' :''We are basing the substitution on the lists by Metraux and Englert (ME:51; HM:310), which are in agreement. Thomson's list is off by one month.'' However, Guy calculated the dates of the new moon for years 1885 to 1887 and showed that Thomson's list fit the phases of the moon for 1886. He concluded that the ancient Rapanui used a lunisolar calendar with ''kotuti'' its embolismic month (AKA "leap month"), and that Thomson chanced to land on Easter Island in a year with a leap month. The days ''hotu'' and ''hiro'' appear to be intercalary. A 28-day calendar month needs one to two intercalary days to keep in phase with the 29½-day lunar month. One of the

rongorongo Rongorongo (Rapa Nui: ) is a system of glyphs discovered in the 19th century on Rapa Nui (Easter Island) that appears to be writing or proto-writing. Numerous attempts at decipherment have been made, with none being successful. Although some c ...

tablets may describe a rule for when to add these days.GUY, Jacques B.M. 2001. "Le calendrier de la tablette Mamari", ''Bulletin du Centre d'Études sur l'Île de Pâques et la Polynésie'' 47:1–4.

References

{{Calendars Easter Island Specific calendars Rongorongo