Astronomically Aligned Religious Structures on Raiatea and Raivavae
as well as the Matariki Festival of 1770 on Easter Island
By Edmundo Edwards
Pacific Islands Research Institute (PIRI)

Generalities about Polynesian Cosmogony and Astronomy

The Polynesians perceived the celestial sphere as several heavens superimposed above each other where different entities and gods lived.  The stars, planets and constellations were the abode of gods, goddesses and other supernatural and immortal beings that resided there from the beginning of time together with the deified spirits of chiefs.[1] Some stars were just lights placed upon the void to direct the gods across the sky.  The number of stars known to the Polynesians was impressive; anthropologist Maud Makemson recorded the names of 772 stars and constellations as well as several astronomical terms while working in different Polynesian islands.

The form and composition of the Polynesian constellations changed between Western and Eastern Polynesia, and could represent different forms that grouped different stars or the same ones gave form to a different figure.  In Eastern Polynesia, the Milky Way had a shark form, and the tail of Scorpio was a fishhook. Other groupings represented a frigate bird and a lizard. One of the Polynesians’ most important navigational aids in these southern waters was Nga Vaka, a double outrigger voyaging canoe formed by Alpha and Beta Centaur and Crux; the higher it appeared upon the horizon the further South you were.  These same stars were supposed to represent different figures in Tonga.  The Southern Cross was called Toloa (wild duck) and Alpha Beta Centaur (yams).[2]  The position of the planets, in relation to certain stars or constellations, especially Mars, could be a good or bad omen.

 The Moon was the abode of Hina, an earth woman formed by the gods of creation who gave birth to mankind and therefore considered the Polynesian Eve.[3]  After a fight with the Gods she escaped into the sky and since then dwells in the moon. Polynesians believed that they could see Hina beating bark cloth (tapa) upon an anvil on the full moon.  The arrival of the full moon was very important because it was believed to be bursting with fertility, therefore it was the best moment to plant and it was celebrated with singing and dancing in most of Polynesia.

Polynesian believed that the chiefs, who could trace their descent from the gods of creation, were endowed with a special power namedMana.  Astronomer priests or skywatchers and navigator’s or wayfinders were the second most respected individuals in Polynesian society.  Although the astronomical knowledge of both skywatchers and wayfinders must have overlapped, it differed in the practice.

 The Navigator or Wayfinder

The wayfinder was held in high esteem due to his knowledge of navigation, which permitted him to search for new lands, to trade, to visit friends and relatives, and to partake in religious or secular festivities on different island groups.  Wayfinders were trained in astronomy, meteorological phenomena, oceanography and animal behavior at a very young age.  Working in different capacities during a voyage, a wayfinder would learn from his peers how to successfully explore the sea of islands that surrounded him.  Wayfinders determined latitude using a Star Compass based on the declinations of principal stars.  Polynesians were especially accurate at dead reckoning being able to determine their approximation to land by careful observation of the stars, currents and drift, winds, and marine birds, etc.  As demonstrated by the experimental voyages of the Hokulea and other oceanic outriggers of the Polynesian Voyaging Society, most of their expeditions must have been successful.  Nevertheless, the observation of the night sky was not limited to navigation but served another important function carried out by the powerful skywatcher priests.

Astronomer Priests or Skywatchers

Astronomer priests (tohunga) usually came from high-ranking families and were chosen at birth to become learned in these “sacred matters.”[4]  Aside from Mangareva and Easter Island there is little mention of astronomer priests elsewhere in Polynesia, although they certainly must have existed.[5]  On Easter Island they lived with their acolytes in circular dwellings named tupa, which had a small tunnel-like-doorway, sometimes oriented towards the rising or setting of specific stars or constellations that were important to determine the Rapanui annual calendar of activities.  Each clan had several tupa usually located near their ceremonial centers (Ahu) or important resource areas.  Skywatchers observed the night sky standing on top of a tupa’s roof.  It is unknown whether the skywatchers had astronomical instruments, however celestial bodies depicted in petroglyphs associated with cupules and dotted lines may be a record of astronomical activities.

The Lunar Calendar

The Polynesian year, was divided into thirteen months one month would be “thrown away” when the lunar year did not coincide with the annual rising of the Pleiades (solar year).  Polynesians used a lunar calendar in which each month began on a full moon and each night carried a different name.  Astronomer priests were responsible for correcting the inherent seasonal and chronological shortcomings of a lunar year in order to effectively establish the cycle of yearly activities.[6]  Polynesian languages share some of the same words for the names of the months, “nights of the Moon”, etc., indicating a common origin tracing back to their ancestral Lapita culture.[7]

The Lunar year was divided into two seasons that were determined by the heliacal and accronic rising of the Pleiades, which in Tropical Polynesia marked an annual cycle of alternating dry and wet seasons that served to determine the time for planting and harvesting of yams and other root crops.  In addition, the names for the months and nights of the Polynesian lunar calendar recognized the moon’s effects on the tides and marine ecosystem for each night of the year, thus determining the optimal time and places for fishing, marine foraging, and available marine resources for each time of the year, every year.

Since the arrival of migrational birds, turtles, and pelagic fish coincided with the accronic or heliacal rising or setting of certain stars or constellations, the astronomer priests used these astronomical events to mark the arrival of migratory species and could foretell when they would come to each island.  Thus Aldebaran marked the time for the breadfruit season in Tropical Polynesia and the accronic rising of the Pleiades on November 16th, marked the opening of the offshore tuna fishing season on the Society Islands, Tuamotu, Gambier and Easter Island.  The setting of the Pleiades on April 16th marked the end of the tuna fishing season on all those islands.

Astronomically Aligned Structures in Polynesia.

Few structures in Western Polynesia have been identified as having an astronomical alignment  or a cardinal orientation.  One of them is the Trilithon in Tonga, which is oriented towards the June solstice.[8]  In Eastern Polynesia, specifically in Mangareva and Easter Island, there are several places where specialized priests observed the solstice or the heliacal rising or setting of the Pleiades; several of their outdoor temples (Marae, Me’ae, Ahu or Heiau) have an astronomical or cardinal orientation.[9]  While carrying out fieldwork in French Polynesia it was observed that several structures on Raivavae and Raiatea appeared to have a cardinal orientation or else seemed to be aligned to the solstices, Aldebaran, Antares, and the Pleiades.  This information appears below.

 Astronomically aligned Marae on Raivavae (The Austral Islands)

Raivavae is located in the Austral Island archipelago 500 kilometers south of Tahiti on the Tropic of Capricorn.  It is a small high island that was surveyed by our team between 1989 and 1991.  During our survey, we only noticed the structures that had a cardinal orientation, but a later study carried out by astronomer Louis Cruchet showed that several of these structures had significant orientations as resumed in Table 1.[10]

Marae type B-1 Type B-3
Aldebaran rise 4 Aldebaran rise 7
Antares set 1 Antares set 6
Not determined 2 Alphard set 2
rise 1
Type B-2 Capella rise 2
set 1
Aldebaran rise 1 Pleiades set 1
Antares set 1 Procyon set 2
Capella rise 1 Spica rise 1
Duubhe set 1 set 1
Pleiades set 2 Cardinal 1
Spica rise 1
Not determined 2
  Type B-4
Type B-3a Aldebaran rise 3
Antares set 1 Antares set 1
Pleiades set 1 Alphard set 1
Procyon ser 1 rise
Cardinal 2 Pleiades set 3
Not determined 0 Spica rise 1
Cardinal 3
Not determined 7

Table 1.- Orientations of Marae on Raivavae

The fact that 14 of Raivavae’s marae are oriented towards the heliacal rising of Aldebaran and 10 of them towards heliacal setting of Antares, cannot be coincidental, and must be part of a ritual cycle of ceremonies and agricultural activities marked by these stars, however this needs further study.

Astronomically aligned marae on Raiatea (Society Islands)

 During our archaeological survey of the Valley of Faaroa on, Raiatea, in 1986, our team found 7 distinctive extended family household settlements associated with a large irrigated terrace complex that occupied the western part of the caldera.  Each of these settlements had one or more religious structures (marae) associated with it.  With the help of astrophysicist Dr. Malcolm Clark, we discovered that 9 marae may have had an astronomical orientation; five seemed to be oriented towards the December solstice, one to the June solstice or rising of the Pleiades, one was cardinally oriented, and two were oriented to Raiatea’s highest peaks.

There is no evidence that astronomer priests in Eastern Polynesia used marae as astronomical measurement devices, however, they would probably use these structures to celebrate rituals that were marked by the accronic or heliacal rising or setting of celestial bodies that were associated to the marae.  Therefore, we can assume that these alignments served only ritual purposes such as to enhance the fertility of their principal crops or to augment the psychic powers derived from such occurrences.  The heliacal rising of Aldebaran together with the Pleiades (Matarii) predicted the ripening of breadfruit and abundance in the Society Islands and that is probably why several ritual structures (marae) there were oriented perpendicular or parallel to the declination of its heliacal rising.

Zone Site N° Ahu Axis Az
C-III 12 Perpendicular 63° June Sunrise or Pleiades
Parallel 108° December Sunrise
C-III 7 Parallel Betelgeuse Rise
A-II 266 Parallel 64° June Sunrise or Pleiades.
A-I 71 Perpendicular 108° December Sunrise
A-I 72 Perpendicular. 108° December Sunrise
A-I 121 Perpendicular 180° North-South
C -IV 1 Parallel 112° December Sunrise

Table 2.  The orientation of religious structures or marae in the Faaroa Valley

The Celebration of the Matariki Festival on Rapa Nui, November 16th, 1770

 On Rapa Nui, as well as in all of Polynesia, the bountiful season (Hora Nui) began with the accronic rising of the Pleiades (Matariki) when they appeared for the first time after twilight on November 16th.  This was a period that lasted 4 months during which normal labor was suspended, the offshore fishing restrictions (Rahui) were lifted, and large schools of tuna fish migrated past the island.  It was one of the most important times of the year, a time when the first harvests were offered to the chiefs and merry ceremonies were held to honour the deified ancestors for their generosity and support.

Plate 1. Detail of a map of Easter Island drawn by Gonzales y Haedo showing the Poike peninsula and its three domes

 Ethnographic sources indicate that important astronomer-priests must have been staying in a cave on the eastern side of Maunga Vai a Heva (Heva’s water), the highest dome of Pua Katiki volcano on Poike peninsula during the nights before and after the Matariki festival.  Edwards was told that a very powerful priest called Heva had lived there in the company of other astronomer priests all of whom were considered to be the foremost wisemen of the island.  Together they had built several small ceremonial platforms with trachyte stone statues on each of the domes and near the base of the cave so that the whole area was considered sacred.  They must have been surprised, the same as everyone else on the island, to see two large ships looming over the horizon shortly after sunrise on November 15th 1770.

Forty-eight years had passed since the first European explorers landed on Rapa Nui in early April 1722, and forty-eight years since the Rapanui had seen muskets and witnessed the first deaths by gunfire.  Captain Felipe Gonzales y Haedo, commanding “The Santa Rosalía” with 70 cannons, and the frigate “San Lorenzo” with 30 more, arrived with a total of 814 men in what would be the Rapanui’s second contact with outsiders after Jacob Roggeween’s disastrous exchange decades before.  After circling the island for a whole day with many islanders gathering on the shore, the Spanish launched some small boats to find anchor at 8 am on November 16th.

Aside from the natural excitement with which the Spanish were greeted, there are several indications that this was a special time of the year for the Rapanui.  The Spanish recorded seeing many people painted with white, yellow, and mostly red pigments—red being the colour that most attracted their attention; in addition, the “important men” had their entire bodies painted bright red with drawings of chickens and “very ugly faces” on their abdomens.  Red was the colour of sacredness in all Polynesia, which is why it would have been particularly important during these festivities, while the chickens were probably symbolic of the bountiful season or fertility.  The figures painted on the abdomen—the seat of knowledge for Polynesians—probably represented the face of god Make Make, the Rapanui creator god.  Although it was customary for the Rapanui to decorate their bodies with paint it seems that the common themes observed by the Spanish were more than just accidental.  The Spanish also recorded seeing a figure called Ko Peka that was about 3.5 m long stuffed with dried grass and hair made out of dark bulrushes.  According to the Spanish, the Rapanui carried it to their different gathering sites and it was meant for amusement.  Obviously this was not a figure that was put together overnight and if the Spanish were correct it was probably used in the first harvest feasts.  Furthermore the Spanish were not met with any degree of hostility but with much excitement, rejoicing, and merriment: they were offered chickens, bananas, and several kinds of tubers, while one small group that ventured inland was conducted to a chief’s house or meeting house where the Rapanui sang and danced for them.  This may be interpreted as the islanders’ natural generosity and cheerful disposition, but it is also possible that for the Rapanui, these were offerings and honours they were paying to the “gods.”  This seems to be the case especially since all Eastern Polynesians believed that during the Matariki Festival certain “gods” descended from the ao (skyworlds) and mingled with ordinary people in the kainga (world of the living).  Although only a few small Spanish groups had explored the island so far, revolving shifts of as many as 400 Rapanui at a time gathered aboard the frigate “San Lorenzo” over the course of the next two days.  The cultural impact of the Spanish explorers visit would clearly not have been as tremendous had they arrived at a different time of the year.  However it multiplied twofold when the Spanish decided to perform a magnanimous ceremony of their own on November 20th, adding a whole other dimension to the festival.

At half past four in the morning of November 20th González y Haedo decided to formalize the possession of Rapa Nui in the name of the Spanish monarch Charles the III, and ordered 125 marines and 125 fully armed seamen instructed in musketry, as well as a few Catholic priests in full religious dress with three wooden crosses, to land in Hanga Ho’onu bay.  On shore, the Spanish were met by hundreds of Rapanui who joined the procession with dancing and singing and responding “ora pro nobis” to the Catholic priests’ litanies along with everyone else as they marched across the North coast straight to Poike peninsula where the Spanish planned to erect the three crosses on each of the trachyte domes of Pua Katiki volcano, right where the most important astronomer priests lived.  As the procession advanced with banners flying and drums beating, they met up with the inhabitants of the Rapanui settlements they passed on the way who offered cloaks to the Catholic priests, as well as hens and pullets (symbols of fertility), crying Make Make, the name of the Rapanui creator god.  Undoubtedly the Rapanui were not merely mimicking the behaviour of the Spanish, but were aware of the religious character of these activities and since everything seemed to coincide with what the Rapanui considered sacred, it is no wonder they were more than happy to follow along, most evidently with a very different interpretation of the same events.  Once the procession arrived at the domes on Pua Katiki volcano, the Spanish dug holes to set up the crosses and an abundant spring of water burst out from the one in the middle dome.[11]  After reading a proclamation, the Catholic priests then proceeded to perform blessings by chanting in Latin next to each of the crosses, which were simultaneously raised on all three mounds at once, while the Spanish officers took possession of the island with all due formalities handing the Rapanui chiefs or priests an official document to sign, which they did with markings of their own design (some drew petroglyph-like birds, others just lines).[12]  Everyone then cheered the king seven times, which was followed by a triple volley of musketry from the whole party, and 21 guns from the ship, which understandably terrorized the Rapanui.  After taking possession, the Spanish climbed down Poike Peninsula, walked back to Hanga Ho’onu, returned to their ship and left on the afternoon of the next day.

It seems interesting that none of the Spanish explorers mentioned the three Rapanui ceremonial platforms that stood on the top of these three mounds, especially since they recorded all other religious structures they passed on the way there.  Since it seems unlikely that they were in disrepair, it is possible that the Spanish simply overlooked them favouring their own activities instead.  Nevertheless, what was so easily ignored by the Spanish is precisely what would have made these events all the more memorable for the Rapanui.  The fact that these strangers arrived at the “right time” and carried out their official ceremonies and religious blessings at the “right place” flaunting their “superiority” and “power” must have been a small coincidence with great repercussions for the Rapanui.  The sacredness of the astronomer-priests dwellings and ceremonial platforms must have increased considerably as a result of the Spanish explorers’ visit, while it is uncertain how it would have affected the social organization of the island and the power of the chiefs and priests in the years that followed.


Buck, P.  1938 “Ethnology of Mangareva” . Honolulu: Bernice P. Bishop Museum  Bulletin 58

Collocott E. E. V. J. 1922. “Tongan Astronomy and Calendar”. Occasional papers of the B. P. Bishop Museum, Vol. VIII— No. 4 Honolulu, Hawaii.

Cruchet, L. 2009 “Archeoastronomy del Iles Australes: Raivavae, Tupuai et Rurutu.

Matari’i N° 26 Avril – Juin , Tahiti.

Edwards, E.  2003  “Raivavae; Archaeological Survey of Raivavae, Austral Islands French Polynesia.” Departement d’ Archéologie, Centre Polinésien de Sciences Humaines “Te Anavaharau.” Inventaire Archéologique de Polynésie Française. Punauia,  Tahiti. Easter Island Foundation Publications. Los Osos CA.

Edwards E. n/d “The Archaeological Survey of Faaroa Valley, Raiatea, French Polynesia”. Departement d’ Archéologie, Centre Polinésien de Sciences Humaines “Te Anavaharau” Inventaire Archéologique de Polynésie Française, Punauia,  Tahiti.

Ferdon E. N. 1987 “Early Tonga, as the explorers saw it . 1616 – 1810”. The University of Arizona Press, Tucson.

Kirch, P. V. and Green R. 2001. “Hawaiiki, Ancestral Polynesia” Cambridge University Press.

Kirch P.V.  2004 “Solstice Observations in Mangareva, French Polynesia”. Archeoastronomy: The Journal of Astronomy and Culture 18 (2004) 1-9

Mellen Blanco F.  1986 “Manuscritos y Documentos Españoles para la Historia de Isla de Pascua”. Biblioteca CEHOPU.

Tragear Edward 1891 “The Maori–Polynesian Comparative Dictionary” Wellington.

[1] Handy, 93

[2] Collocott, 3

[3] Tragear, 155

[4] Handy, 29

[5] Kirch P.V. 2008: 4

[6] Kirch, P. V. and Green R. 2002: 273

[7] Ibid., 267-272

[8] Ferdon, 84

[9] Kirch 2008: 3; Buck 1938: 57

[10] Cruchet, 19 – 20

[11] Considering the nature of the terrain, it is hard to believe that water miraculously bust out of a hole there.

[12] Other Polynesians may have developed a form of writing, however the Rapanui are the only ones who can prove it.  There are 28 different objects that have rongorongo figures carved on them (mainly wooden tablets, but also small stones, staffs of power, breastplates, and votive figures).  Attempts to decipher rongorongo have not been successful although it is evidently pictographic and written in reverse boustrophedon style.  Some scholars suggest that the Rapanui invented it after European contact, possibly after the arrival of the Spanish in 1770.  According to Rapanui oral tradition rongorongo script was developed by chief Ngaara I, who was paramount chief at the time of Spanish discovery, and it was he who set up several rongorongo schools in different parts of the island in the early 1800’s.  Unfortunately the script was lost when diseases killed all those who knew how to write or read it.