There were probably 392 glyphs on side a of the C tablet. The last glyph should therefore be in right ascension day 183 (September 20) + 392 - 365 = 210 (October 17), i.e. 27 days later in the year. However, the rongorongo writers seem to have counted with 366 (= 2 * 183) instead of 365 in order to keep their nakshatra dates in proper order.
For instance should the nakshatra date corresponding to heliacal oJULY 28 (209) be equal to 209 + 183 - 366 = 392 - 366 = 26 (oJANUARY 26), when Polaris would have risen with the Sun - according to my (and probably also the rongorongo writers) simple extrapolations disregarding the proper motion of a star:
| oJULY 2 |
3 |
4 (185) |
5 |
6 |
7 |
380 |
| ●JULY 7 |
8 |
9 |
10 |
11 |
12 (193) |
| JULY 18 (199) |
19 |
20 |
21 |
22 |
23 |
| no glyph |
 |
 |
 |
 |
 |
| Ca1-1 |
Ca1-2 |
Ca1-3 |
Ca1-4 |
Ca1-5 |
| koia |
ki te hoea |
ki te henua |
te rima te hau tea |
haga i te mea ke |
| Alchita, Ma Wei (183.1), Minkar (183.7), ρ Centauri (183.9) |
PÁLIDA (184.6), Megrez (184.9) |
Hasta-13 / Chariot-28 |
Chang Sha (186.3) |
INTROMETIDA (187.4), ACRUX (187.5) |
γ Com. Berenicis (188.0), σ Centauri (188.1), ALGORAB (188.5), GACRUX (188.7) |
| GIENAH (185.1), ε Muscae (185.2), ζ Crucis (185.4), ZANIAH (185.9) |
| September 20 |
21 (264) |
EQUINOX |
23 |
24 |
25 |
| 'August 24 (236) |
25 |
26 |
27 |
28 |
29 |
| "August 10 (222) |
11 |
12 |
13 |
14 |
15 |
| 22-7 |
oJULY (*124) |
24 |
25 |
26 |
27 |
28 (209) |
| ●JULY 27 |
28 (*129) |
29 |
30 |
31 |
●AUGUST 1 |
2 (214) |
| AUGUST 7 |
8 (*140) |
9 |
10 |
11 |
12 |
13 (225) |
 |
 |
 |
 |
 |
 |
 |
| *Ca14-23 |
*Ca14-24 |
*Ca14-25 |
*Ca14-26 |
*Ca14-27 |
*Ca14-28 |
*Ca14-29 (392) |
| kua heheu |
te henua |
te honu kau |
manu kake rua |
te henua |
te honu |
te rima |
| 71 Virginis (203.6) |
no star listed (204) |
Heze (205.0), Southern Pinwheel Galaxy (205.7) |
ε Centauri (206.3), κ Oct. (206.4) |
no star listed (207) |
τ Bootis (208.2), Benetnash (208.5), ν Centauri (208.7), μ Centauri, υ Bootis (208.8) |
no star listed (209) |
| October 10 |
11 |
12 (285) |
13 |
14 |
15 |
16 |
| 'September 13 |
14 |
15 |
16 (*179) |
17 |
18 (261) |
19 |
| "August 30 |
31 |
"September 1 |
2 (*165) |
3 |
4 |
5 (248) |
| NAKSHATRA DATES: |
| oJANUARY 20 |
21 |
22 |
23 |
24 |
25 |
26 (392) |
| ●JANUARY 25 |
26 |
27 |
28 (*314) |
29 |
30 |
31 (31) |
| FEBRUARY 5 |
6 |
7 |
8 (*325) |
9 (40) |
10 |
11 (408) |
| Ksora (20.1), ω Andromedae (20.6), γ Phoenicis (20.8) |
δ Phoenicis (21.5) |
υ Andromedae (22.9) |
ACHERNAR (23.3), χ Andromedae (23.6), τ Andromedae (23.9) |
τ Ceti (24.7) |
no star listed (25) |
ANA-NIA |
| χ Ceti (26.1), POLARIS, Baten Kaitos (26.6), Metallah (26.9) |
| April 10 (100) |
11 |
12 |
13 |
14 |
15 |
16 (*26) |
| 3-14 (73) |
'March 15 |
16 |
17 |
18 |
19 (78) |
20 (*364) |
| "Febr 28 (59) |
"March 1 |
2 |
3 |
4 |
5 (64) |
6 (*350) |
| oJULY 29 (210) |
30 |
31 |
oAUGUST 1 |
| ●AUGUST 3 |
4 |
5 |
6 (218) |
| AUGUST 14 |
15 |
16 |
17 (229) |
 |
 |
 |
 |
| Cb1-1 |
Cb1-2 |
Cb1-3 |
Cb1-4 (396) |
| E tupu - ki roto |
o te hau tea |
ki te henua - te maro |
| MUPHRID (210.1), ζ Centauri (210.3) |
φ Centauri (211.0), υ¹ Centauri (211.1), υ² Centauri (211.8), τ Virginis (211.9) |
Agena (212.1), θ Apodis (212.5), THUBAN (212.8) |
14h (213.1) |
| π HYDRAE, χ Centauri (213.0), Menkent (213.1) |
| October 17 (290) |
18 |
19 |
20 |
| 'September 20 |
21 |
EQUINOX |
23 (266) |
| "September 6 |
7 |
8 |
9 (252) |
| NAKSHATRA DATES: |
| oJANUARY 27 (393) |
28 |
29 |
30 |
| ●FEBRUARY 1 (32) |
2 |
3 |
4 |
| FEBRUARY 12 (409) |
13 |
14 |
15 |
| Al Sharatain-1 / Ashvini-1 / Bond-16 / Mahrū-sha-rishu-ku-1 |
ι Arietis (28.0), λ Arietis (28.2), υ Ceti (28.8) |
ALRISHA, χ Phoenicis (29.2), Alamak (29.7) |
Arku-sha-rishu-ku-2 |
| 2h (30.4) |
| Segin, Mesarthim, ψ Phoenicis (27.2), SHERATAN, φ Phoenicis (27.4) |
κ Arietis (30.3), HAMAL (30.5) Alkes
|
| April 17 (107) |
18 |
19 (*29) |
20 |
| EQUINOX (80) |
'March 22 |
23 |
24 |
| "March 7 (66) |
8 |
9 (*354) |
10 |
Early I had assumed the beginning of the C text was at the current (at the time of rongorongo) northern spring equinox with Polaris at the end of side a. However, the honu glyphs at the end of side a and at the beginning of side b clearly demonstrate a continuity, and the (Dry Earth) Turtle should also on Easter Island have represented the opposite side of the sky compared to the Water accumulated in the Underworld:
... An iconographic study by Jeff Kowalski suggests a cosmological layout for the Nunnery. The higher placement of the North Building, with its 13 exterior doorways (reflecting the 13 layers of heaven), and the celestial serpents surmounting the huts identify it with the celestial sphere. The iconography of the West Building, with 7 exterior doorways (7 is the mystic number of the earth's surface), and figures of Pawahtun - the earth god as a turtle - indicate this to be the Middleworld, the place of the sun's descent into the Underworld. The East Building has mosaic elements reflecting the old war cult of Teotihuacan, where tradition had it that the sun was born; thus, this may also be Middleworld, the place of the rising sun. Finally, the South Building has 9 exterior doorways (the Underworld or Xibalba had 9 layers), and has the lowest placement in the compex; it thus seems to be associated with death and the nether regions ...
There were 2 basic lists of prominent stars, first one beginning early in the northern year and ending at Spica (Ana-roto) whereas the second one was beginning at Spica:
| BABYLONIAN ECLIPTIC CONSTELLATIONS: |
| 0 |
1-iku |
Field measure |
τ (Anunitum) Pisces |
16.5 |
April 6 (96) |
| |
| 1 |
Mahrū-sha-rishu-ku |
Front of the Head of Ku |
β (Sheratan), γ (Mesarthim) Arietis |
27.4 |
April 17 (107) |
| 2 |
Arku-sha-rishu-ku |
Back of the Head of Ku |
α (Hamal) Arietis |
30.5 |
April 20 (110) |
| 3 |
Temennu |
Foundation Stone |
η (Alcyone) Tauri |
56.1 |
May 16 (136) |
| 4 |
Pidnu-sha-Shame |
Furrow of Heaven |
α (Aldebaran) Tauri |
68.2 |
May 28 (148) |
| 5 |
Shur-narkabti-sha-iltanu |
Star in the Bull towards the north |
β (El Nath) Tauri |
80.9 |
June 9 (160) |
| 6 |
Shur-narkabti-sha-shūtū |
Star in the Bull towards the south |
ζ (Heavenly Gate) Tauri |
84.0 |
June 13 (164) |
| 7 |
Maru-sha-pu-u-mash-mashu |
Front of the Mouth of the Twins |
η (Tejat Prior) Gemini |
93.4 |
June 22 (173) |
| 8 |
Arkū-sha-pu-u-mash-mashu |
Back of the Mouth of the Twins |
μ (Tejat Posterior) Gemini |
95.4 |
June 24 (175) |
| 9 |
Mash-mashu-sha-Risū |
Twins of the Shepherd (?) |
γ (Alhena) Gemini |
103.8 |
July 2 (183) |
| 10 |
Mash-mashu-Mahrū |
Western One of the Twins |
α (Castor) Gemini |
113.4 |
July 12 (193) |
| |
| 11 |
Mash-mashu-arkū |
Eastern One of the Twins |
β (Pollux) Gemini |
116.2 |
July 15 (196) |
| 12 |
Arkū-sha-nangaru-sha-shūtu |
Southeast Star in the Crab |
δ (Ascellus Australis) Cancri |
131.4 |
July 30 (211) |
| 13 |
Rishu A. |
Head of the Lion |
ε (Ras Elaset Australis) Leonis |
146.6 |
Aug 14 (226) |
| 14 |
Sharru |
King |
α (Regulus) Leonis |
152.7 |
Aug 20 (232) |
| 15 |
Maru-sha-arkat-Sharru |
4th Son behind the King |
ρ (Shir) Leonis |
158.9 |
Aug 26 (238) |
| 16 |
Zibbat A. |
Tail of the Lion |
β (Denebola) Leonis |
178.3 |
Sept 15 (258) |
| 17 |
Shēpu-arkū sha-A |
Hind Leg of the Lion |
β (Alaraph) Virginis |
178.6 |
Sept 15 (258) |
| 18 |
Shur-mahrū-shirū |
Front or West Shur (?) |
γ (Porrima) Virginis |
191.5 |
Sept 28 (271) |
| |
| 19 |
Sa-Sha-Shirū |
Virgin's Girdle |
α (Spica) Virginis |
202.7 |
Oct 9 (282) |
| CHINESE STATIONS: |
| 1 |
Horn |
α Virginis (Spica) |
Crocodile |
(202.7) |
Oct 9 (282) |
282 = 265 + 17 |
| 2 |
Neck |
κ Virginis |
Dragon |
(214.8) |
Oct 21 (294) |
294 = 282 + 12 |
| 3 |
Root |
α Librae (Zuben Elgenubi) |
Badger |
(224.2) |
Oct 31 (304) |
304 = 295 + 9 |
| 4 |
Room |
π Scorpii (Vrischika) |
Hare |
(241.3) |
Nov 17 (321) |
321 = 304 + 17 |
| 5 |
Heart |
σ Scorpii |
Fox |
(247.0) |
Nov 23 (327) |
327 = 321 + 6 |
| 6 |
Tail |
μ Scorpii (Denebakrab) |
Tiger |
(254.7) |
Nov 30 (334) |
334 = 327 + 9 |
| 7 |
Winnowing Basket |
γ Sagittarii (Nash) |
Leopard |
(273.7) |
Dec 19 (353) |
353 = 334 + 19 |
| December solstice |
| 8 |
South Dipper |
φ Sagittarii (?) |
Unicorn |
(284.0) |
Dec 30 (364) |
364 = 353 + 11 |
| 9 |
Ox / Herd Boy |
β Capricornii (Dabih) |
Buffalo |
(308.0) |
Jan 23 (388) |
388 = 364 + 24 |
| 10 |
Girl |
ε Aquarii (Albali) |
Bat |
(314.8) |
Jan 29 (394) |
394 = 388 + 6 |
| 11 |
Emptiness |
β Aquarii (Sadalsud) |
Rat |
(325.9) |
Feb 9 (405) |
405 = 394 + 11 |
| 12 |
Rooftop |
α Aquarii (Sadalmelik) |
Swallow |
(334.6) |
Feb 18 (414) |
414 = 405 + 9 |
| 13 |
House |
α Pegasi (Markab) |
Pig |
(349.5) |
Mar 5 (429) |
429 = 414 + 15 |
| March equinox |
| 14 |
Wall |
γ Pegasi (Algenib) |
Porcupine |
(1.8) |
Mar 22 (81) |
81 |
| 15 |
Legs |
η Andromedae (?) |
Wolf |
(11.4) |
Apr 1 (91) |
91 = 81 + 10 |
| 16 |
Bond |
β Arietis (Sheratan) |
Dog |
(27.4) |
Apr 17 (107) |
107 = 91 + 16 |
| 17 |
Stomach |
4¹ Arietis (Bharani) |
Pheasant |
(41.4) |
May 1 (121) |
121 = 107 + 14 |
| 18 |
Hairy Head |
η Tauri (Alcyone) (?) |
Cockerel |
(56.1) |
May 16 (136) |
136 = 121 + 15 |
| 19 |
Net |
ε Tauri (Ain) |
Crow |
(65.7) |
May 25 (145) |
145 = 136 + 9 |
| 20 |
Turtle |
λ Orionis (Heka) |
Monkey |
(83.2) |
Jun 12 (163) |
163 = 145 + 18 |
| 21 |
Three Stars |
ζ Orionis (Alnitak) |
Gibbon |
(84.7) |
Jun 13 (164) |
164 = 163 + 1 |
| June solstice |
| 22 |
Well |
μ Gemini (Tejat Posterior) |
Tapir |
(95.4) |
Jun 24 (175) |
175 = 164 + 11 |
| 23 |
Ghost |
ρ Gemini ? |
Goat |
(112.1) |
Jul 11 (192) |
192 = 175 + 17 |
| 24 |
Willow |
δ Hydrae |
Stag |
(129.6) |
Jul 28 (209) |
209 = 192 + 17 |
| 25 |
Star |
α Hydrae (Alphard) |
Horse |
(142.3) |
Aug 10 (222) |
222 = 209 + 11 |
| 26 |
Extended Net |
ε Hydrae / μ Hydrae |
Ox |
(131.9 / 157.1) |
Jul 30 (211) / Aug 25 (237) |
237 = 222 + 15 |
| 27 |
Wings |
α Crateris (Alkes) |
Snake |
(165.6) |
Sep 2 (245) |
245 = 237 + 8 |
| 28 |
Chariot |
γ Corvi (Gienah) |
Worm |
(185.1) |
Sep 22 (265) |
265 = 245 + 20 |
| September equinox |
The Head of Ku (Rishu Ku) was beginning at the First Point of Aries (Sheratan, β Arietis), which in rongorongo times corresponded to April 17 (*27), i.e. to day number 80 + 27 = 107, where 107 could have been regarded as the difference between 8 double synodic lunar months - as 8 * 59 = number of day positions on the G tablet - and the 365 days of the Sun year.
183 days later the Head of Ku could be seen close to the Full Moon, nakshatra wise indicating that the Sun was now rising together with Muphrid (η Bootis) in day *27 + 183 = *210 (October 17, 290).
At the time when the equinoctial colure was at Elnath (β Tauri) - rising 2 days after Rigel (β Orionis) - this was 80 precessional days earlier than March 21. Heliacal Sirrah should at that ancient time have been in oDECEMBER 31.
... Fanciful, assuredly, but neither the Milky Way nor the terrestrial Ganges offered any basis for the imagery of a river flowing to the four quarters of the earth 'for the purification of the three worlds'. One cannot get away from the 'implex' and it is now necessary to consider the tale of a new skeleton map, alias skambha: the equinoctial colure had shifted to a position where it ran through stars of Auriga and through Rigel. Skambha, as we have said, was the World Tree consisting mostly of celestial coordinates, a kind of wildly imaginative armillary sphere. It all had to shift when one coordinate shifted ...
| oMARCH 16 |
17 |
18 |
19 (78 = 6 * 13) |
20 |
EQUINOX |
| EQUINOX |
●MARCH 22 |
23 |
24 |
25 |
26 (85) |
| APRIL 1 |
2 (92) |
3 |
4 (*14) |
5 |
6 (96) |
 |
 |
 |
 |
 |
 |
| Ga1-11 |
Ga1-12 |
Ga1-13 |
Ga1-14 |
Ga1-15 |
Ga1-16 |
| HAEDUS II (75.9) |
5h (76.1) |
μ AURIGAE, μ LEPORIS (77.6) |
ĸ Leporis (78.0), RIGEL (78.1), Flaming Star (78.2), CAPELLA (78.4), ο Columbae, τ Orionis (78.8)
Thuban
|
λ AURIGAE (79.0), λ LEPORIS (79.6), ρ Aurigae (79.7)
Arcturus
|
σ Aurigae (80.4), Bellatrix, Saif al Jabbar (80.7), ELNATH (80.9) |
| ε Leporis (76.0), CURSA (76.4), λ Eridani (76.7) |
| June 4 |
5 |
6 (157 = 314 / 2) |
7 |
8 |
9 (2 * 80) |
| 'May 8 (128) |
9 |
10 (*50) |
11 |
12 (2 * 66) |
13 |
| "April 24 (*34) |
25 |
26 (116 = 4 * 29) |
27 |
28 (2 * 59) |
29 |
| NAKSHATRA DATES: |
| oSEPTEMBER 15 |
16 |
17 |
18 (261 = 9 * 29) |
19 |
20 |
| ●SEPTEMBER 20 |
21 |
EQUINOX |
23 (266) |
24 |
25 (*188) |
| OCTOBER 1 |
2 |
3 |
4 (277) |
5 |
6 (*199) |
| 17h (258.7) |
Mula-19 |
NODUS I (260.0), π Herculis (260.7), Ras Algethi (260.8) |
Sarin (261.0), ο Ophiuchi (261.4)
Alrisha
|
ξ Ophiuchi (262.2), θ Ophiuchi, ν Serpentis, ζ, ι Apodis (262.4), ι Arae (262.8), ρ Herculis (262.9) |
β, γ Arae (263.3), κ Arae (263.5), σ Ophiuchi (263.6) |
| no star listed (258) |
Sabik (259.7), η SCORPII (259.9) |
| December 4 |
5 |
6 |
7 (*261) |
8 |
9 |
| 'November 7 |
8 |
9 |
10 (314) |
11 |
12 |
| "October 24 |
25 |
26 |
27 (300) |
28 |
29 (*222) |
When in rongorongo times Sirrah was close to the Full Moon it meant the Sun had reached the first stars of Raven, down at the Coal-sack. The great fire in the sky was no longer burning quickly as before but his spirit remained in his live coals. 
| oJULY 2 |
3 |
4 (185) |
5 |
6 |
7 |
| ●JULY 7 |
8 |
9 |
10 |
11 |
12 (193) |
| JULY 18 (199) |
19 |
20 |
21 |
22 |
23 |
| no glyph |
|
|
|
|
|
| Ca1-1 |
Ca1-2 |
Ca1-3 |
Ca1-4 |
Ca1-5 |
| koia |
ki te hoea |
ki te henua |
te rima te hau tea |
haga i te mea ke |
| Alchita, Ma Wei (183.1), Minkar (183.7), ρ Centauri (183.9) |
PÁLIDA (184.6), Megrez (184.9) |
Hasta-13 / Chariot-28 |
Chang Sha (186.3) |
INTROMETIDA (187.4), ACRUX (187.5) |
γ Com. Berenicis (188.0), σ Centauri (188.1), ALGORAB (188.5), GACRUX (188.7) |
| GIENAH (185.1), ε Muscae (185.2), ζ Crucis (185.4), ZANIAH (185.9) |
| September 20 (263) |
21 |
EQUINOX |
23 |
24 |
25 |
| 'August 24 (236) |
25 |
26 |
27 |
28 |
29 |
| "August 10 (222) |
11 |
12 |
13 |
14 |
15 |
| NAKSHATRA DATES: |
| oDECEMBER 31 |
oJANUARY 1 |
2 |
3 (368) |
4 |
5 (*290) |
| ●JANUARY 5 |
6 |
7 |
8 |
9 (*294) |
10 (375) |
| JANUARY 16 |
17 |
18 (383) |
19 (*304) |
20 |
21 |
| Al Fargh al Thāni-25 |
Uttara Bhādrapadā-27 / Wall-14 |
χ Pegasi (2.1), θ Andromedae (2.7) |
σ Andromedae (3.0), ι Ceti (3.3), ζ Tucanae (3.5), ρ Andromedae, π Tucanae (3.7) |
no star listed (4) |
ANKAA, κ PHOENICIS (5.0) Alphard
|
| 0h (365.25) |
| Caph, SIRRAH (0.5), ε Phoenicis, γ³ Oct. (0.8) |
ο Oct. (1.3), ALGENIB PEGASI (1.8) |
| EQUINOX |
March 22 |
23 |
24 (*3) |
25 (84) |
26 (*370) |
| 'February 22 (53) |
TERMINALIA |
24 |
25 |
26 |
27 (*343) |
| "February 8 (2-8) |
9 (40) |
10 |
11 |
12 |
13 (*329) |
|