The Copan Baseline: K'atun 9.11.0.0.0
and the Three Hearthstones in Orion
MICHAEL
J.
GROFE
Abstract
The acropolis in the Classic Maya city of
Copan occupies a central position in the
Copan Valley. On either side of the valley,
Stela 10 and Stela 12 form a 6.5-km baseline
that appears to have served an astronomical
purpose. Taking into account the hieroglyphic
texts on both Stela 10 and Stela 12, this article provides a new interpretation of the
purpose of the Copan baseline as a commem-•
oration of astronomical observations on the
eastern horizon, involving the sunrise on the
K'atun ending 9.11.0.0.0 at the identical azimuth as the rising of Na'ir al Saif, the brightest star in Orion's Sword, a nebulous region
recognized by the K'iche' Maya as the smoke
from the hearth fire in an asterism known as
the Three Hearthstones of Alnitak, Saiph,
and Rigel. In the text from Stela 12, the ruler
K'ahk' Uti' Witz' K'awiil is said to have witnessed the First Three Hearthstones at the
"edge of the sky," a phrase commonly referenced in widely shared texts dealing with the
mythical start of the Long Count in 3114 BC.
However, this is the only known text with a
specific historical reference to an observation of the Three Hearthstones. Evoking the
cosmological rebirth of the Sun, the Copan
baseline and its associated inscription appear
to commemorate K'atun 9.11.0.0.0, when the
Sun rose at the same azimuth as that of the
central fire in the Three Hearthstones. The
evidence from this article specifically both
supports the 584285 GMT calendar correlation and provides additional evidence to
support the hypothesis that the asterism of
the Three Hearthstones from Classic period
Maya texts is directly ancestral to the K'iche'
asterism with the same name.
Resumen
La acropolis de Ia ciudad maya clasico de
Copan ocupa una posicion central en el valle
de Copan. A cada !ado del valle, la Estela 10
y Ia Estela 12 forman una linea de base de 6.5
km que parece haber servido a un proposito
astronomico. Teniendo en cuenta los textos jeroglificos tanto en la Estela 10 y Ia Estela 12,
este articulo ofrece una nueva interpretacion
del proposito de la linea de base de Copan
como una conmemoracion de las observaciones astronomicas en el horizonte oriental, que
implica la salida del sol en el final de K'atun
9.11.0.0 0,0 en el acimut identica como la salida de Na'ir al Saif, la estrella mas brillante
de la espada de Orion, una region nebulosa
reconocido por el K'iche' Maya como el humo
del fuego del hogar en un asterismo conocido
como las tres piedras de hogar de Alnitak,
Saiph, y Rigel. En el texto de la Estela 12, el
gobernante K'ahk' Uti' Witz' K'awiil se dice
que ha sido testigo de las tres primeras pie-
Michael J. Grote, a specialist in Maya hieroglyphic writing, archaeoastronomy, comparative mythology, and cacao, is particularly interested in the analysis of Maya deep-time intervals and the confluence of mythological narratives and astronomical science in Mesoamerica . In his doctoral research at the University of California at Davis, he explored a new astronomical interpretation of the Serpent
Series within the Dresden Codex that incorporates precise measurements of the sidereal year, and he is currently expanding this research to systematically explore the theoretical astronomy found throughout the inscriptions. He leads multiple field courses with the
Maya Exploration Center and currently teaches cultural anthropology, archaeology, physical anthropology, and linguistics at American River College and Sacramento City College in California .
© 2012-2013 by the University of Texas Press
dras de hagar en el "borde del cielo," una
frase comunmente se hace referencia en los
textos ampliamente compartidos que se ocupan de la mftica inicio de la Cuenta Larga en
3114 aC. Sin embargo, esto es el unico texto
conocido con una referencia hist6rica especffica a una observaci6n de las tres piedras
de hagar. Evocando el renacimiento cosmo16gico del Sol, la linea de base de Copan y
su inscripci6n asociada parecen conmemorar K'atun 9.11.0.0.0, cuando el Sol se levant6
en el mismo azimut que la del fuego central
en las tres piedras de hagar. La evidencia de
este articulo especfficamente tanto apoya el
584285 GMT correlaci6n calendario, y proporciona evidencia adicional para apoyar la
hip6tesis de que el asterismo de las tres piedras de hagar, dentro de los textos mayas del
epoca Clasica, es directamente ancestral a asterismo K'iche' con el mismo nombre.
The acropolis in the Classic Maya city of Copan occupies a central position in the Copan Valley. On ei-
FIGURE 1.
ther side of the valley, Stela 10 and Stela 12 form a
6.5-km baseline that aligns with the southern side of
the central acropolis, and it appears to have served
an astronomical purpose (Figure 1). These two stelae
were erected by Ruler 12 of Copan, whose full name
reads K'ahk' Uti' Witz' K'awiil (Stuart 2007). Nicknamed "Smoke Imix" (Grube and Martin 2000:201),
Ruler 12 dedicated Stela 10 and Stela 12 as part of a
larger sculpture program of seven monuments with
dates leading up to and commemorating the K'atun
ending on the Long Count date 9.11.0.0.0. 1 Several
authors have suggested that Stela 10 and Stela 12
intend to mark positions of the Sun on the western
horizon, thus demarcating two specific days in the
tropical year. However, using either of the widely
accepted Goodman-Martinez-Thompson (GMT)
correlations between the Maya and Christian chronologies, neither of the Initial Series dates on either stela appears to corroborate the proposed solar
alignments suggested by the baseline.
All previous analyses of the Copan baseline
have assumed that it is intended to indicate a solar
Map of Copan, showing Copan baseline: (left) Stela 10; (right) Stela 12 (after Morley 1920).
VOLUME XXV 2012-2013
55
alignment on the western horizon or that the Initial
Series dates on Stela 10 and Stela 12 should necessarily correspond to one of the two days on which
the Sun appears at this western azimuth position.
Taking into account the hieroglyphic texts on both
Stela 10 and Stela 12 and the associated monuments
dedicated by K'ahk' Uti' Witz' K'awiil, this article
provides a new interpretation of the purpose of the
Copan baseline as a commemoration of both solar
and stellar observations on the eastern horizon that
specifically target the sunrise on 9.11.0.0.0 and the
asterism of the Three Hearthstones in Orion, referenced in the text from Stela 12 and known among
the contemporary K'iche'.
Previous Analyses of the Copan Baseline
Following his explorations of Copan, Colonel !uan
Galindo (1835) first mentioned Stela 10 and Stela 12,
but it was Herbert Spinden (1913:164) who first suggested that these two stelae form an intentional eastwest sight line. Under the auspices of the Carnegie
Institution, Arthur Carpenter obtained a magnetic
compass bearing of Stela 10 from Stela 12, as well
as of the sunset azimuth on March 8, 1916 (Morley
1926). Using this data, Robert Wheeler Willson calculated that the Sun would set 8°13' north of west
directly behind Stela 10 when seen from the position of Stela 12 (Figure 2), 20.3 days after the vernal
equinox on April 9, and 20.6 days prior to the autumnal equinox on September 2 (Morley 1920:132136). Citing Willson, who calculated the bearing as
N 81°47' W (an azimuth of 278°13'), Morley (1920:
133) mistakenly restates the second of these days as
September 10.
Considering an earlier magnetic bearing of
N 86°46' W together with the magnetic declination of 6° obtained from George B. Gordon (1896),
Willson recalculated another bearing of N 80°46' W
(azimuth 279°14'), which shifted the dates by three
days forward from April 9 and three days backward
from the September 2 date. Morley (1920:134) records these dates as April 12 and incorrectly as September 7, based on his prior error. Accompanying
Morley in 1926, John Lindsay from the Carnegie
Department of Terrestrial Magnetism confirmed
an actual sighting of sunset behind the baseline on
56
ARCHAEOASTRONOMY
April 12 at a bearing of N 81°9' W (an azimuth of
278°51'), noting that the reciprocal sunset would occur on August 30 (Morley 1926:277-282). Nevertheless, several authors (Aldana 2002; Aveni 1977,
1980, 2001; Baudez 1987) have continued to state
that the dates for the sunset behind the baseline
are April 12 and September 1, but this latter date
is again incorrect and impossible, and apparently
based on an attempt to correct Morley's original error without accounting for the subsequent three-day
subtraction confirmed by Lindsay's measurement.
Spinden (1930:101) notes that the two dates should
be April 12 and its reciprocal date, August 30.
In his unpublished notes from the Peabody Museum, Gordon calculated that Stela 10 stands at the
crest of a hill 4.5 km west of the central acropolis
at an elevation 228 m above the Great Plaza, while
Stela 12 stands on a hillside 2.5 km east of the central
acropolis and 188.6 m above it (Morley 1920:133).
Providing a revision of these measurements, Lindsay
and Morley give the distance between the two ste-
c
Stela 12
East
FIGURE 2. View of sunset behind Stela 10, as viewed from
Stela 12 (from Morley et a!. 1983:564).
lae as 6,625.5 m (21 ,734 ft), with Stela 10 at an elevation of 847 m (2,779 ft) and Stela 12 at an elevation
of 778.1 m (2,553 ft) above sea level. Finally, they estimate the geographic coordinates of the two monuments, with Stela 10 at 14°51' N, 89°8.1' W; and
Stela 12 at 14°50.4' N, 89°4.5' W (Morley 1926).
Given the multiple errors as well as the significant differences in results obtained by several researchers, I resolved to gather additional data
using methods unavailable to previous investigators. Based on measurements taken on-site using a
handheld, digital GPS unit, I obtained the coordinates of Stela 10 as 14°50'31.2" Nand 89°11'3.5" W
at an elevation of 827 m, slightly lower than either
Morley's or Gordon's estimate. Stela 12 appeared
at 14°49'58.56" N and 89°7'26.7" W at an elevation
of 758 m, showing the same 20-m difference from
Morley's calculation, which may result from fluctuating atmospheric pressure at the same time of day.
However, the measurements I obtained nicely preserve the same relative elevation difference Lindsay
calculated between the two stelae. The coordinates I
obtained provide an azimuth bearing of 278°51'37"
and a distance of 6,551 m using a spherical Earth
model, or a bearing of278°48'20" and a true distance
of 6,559 m using Thaddeus Vincenty's model for an
ellipsoidal Earth. 2 These measurements closely conform to Lindsay's measurement of 278°51' (Morley
1926). Even within a large margin of error of ±5 m
for each of the GPS coordinates obtained, the azimuth bearing still generally holds within 278°25' to
279°8', which remains relatively consistent as a solar alignment, given that the apparent width of the
solar disk is approximately half a degree, or 30'. As
Lindsay notes, Stela 10 would have to shift by 41.2 m
(135 ft) north or south in order to change the date of
the alignment by one day (Morley 1926).
Stela 10 appears at an altitude of .6°, or 36' above
the true horizon from the point of observation at
Stela 12. However, from this perspective Stela 10
is not exactly against the sky, as there is a 940-m
hill 1.6 km behind it just to the southwest of Cerro
Gavil<in, bringing the skyline to an altitude of about
1o above the true horizon, or about half a degree
above Stela 10. Because of this discrepancy, Claude
Baudez (1987) criticized the proposals that Stela 10
would have been used as a sight line for solar observations. In response, Anthony Aveni and colleagues
(1993:88) note that Stela 10 indeed "lies V2°, or one
sun disk, below the skyline," but they contend that
such a placement does not disqualify it as an effective solar measuring device. Furthermore, they
contend that Baudez's assumptions to the contrary
demonstrate a decidedly "ethnocentric posture."
An azimuth of 278°48'20" to 278°51'37" confirms
Lindsay's measurement of 278°51', thereby repeating the dates of Lindsay's observations. Combined
with the altitude of 1°, the current dates for the observation of the Sun behind Stela 10 from the perspective of Stela 12 correspond with Aprilll-12 and
August 29-30, depending on the time relative to the
insertion of the intercalary leap year. Due to slight
changes in the Earth's elliptical orbit and the resulting changes in the Earth's differential velocity, these
dates would have been slightly shifted on April 12
and August 30-31 in AD 652, at the proposed time
of the dedication of the baseline monuments, using
either of the two widely accepted GMT correlation
constants. 3
As a result of Willson's and Lindsay's calculations, Morley concluded that the two stelae were
used to time the yearly burning of the milpas to prepare them for planting in early April. Prior to the
general acceptance of the GMT correlation of the
Long Count with the Gregorian calendar, Morley
predicted that the dates inscribed on Stela 10 and
Stela 12 would enable an exact correlation with the
above dates on which the Sun sets behind the baseline (Morley 1920:134).
Following Morley, Aveni (1977:9-14, 1980:240244, 2001:251-255) proposed that the solar alignment of the Copan baseline represents a system with
which the Maya were observing a division of the
tropical year into 20-day segments, given that the
Sun sets on the baseline approximately 20 days after
the vernal equinox and 20 days prior to the first solar
zenith at Copan. Likewise, Aveni suggested that this
repeats for the second solar zenith, approximately
20 days prior to when the sunset again would appear
on the baseline, some 20 days prior to the autumnal equinox. However, the confirmed baseline date
of April 12 is actually 22-23 days after the vernal
VOLUME XXV 2012-2013
57
equinox and 18-19 days prior to the first zenith,
while August 30 (though Aveni gives September 1 in
error) is 19-20 days after the second zenith and 2122 days prior to the autumnal equinox. Moreover,
Aveni's proposal did not directly take into account
the inscribed dates of Stela 10 and Stela 12 and their
associated texts.
Despite the general acceptance of the two GMT
correlations, neither of the dates on either Stela 10
or Stela 12 reveals any correspondence with either
April 12 or August 30. This led Gerardo Aldana
(2002) to propose that the eroded Initial Series Long
Count date on Stela 12 had been misread and that
both of the GMT correlations may be incorrect.
However, Aldana based this, in part, on an interpretation of Morley's drawing of Stela 12 that did not
include the top portion of the monument, which
missing at the time Morley recorded the inscriptions. The missing fragment has since been identified and reattached to Stela 12 (Schele 1992:1),
revealing the Wind Deity as the Haab patron for the
month of Mak (Figure 3). Therefore, it appears that
Morley's original reading of the date on Stela 12 is
correct as 9.10.15.0.0, 6 Ajaw 13 Mak. This reading
is further supported by the presence of the expected
lunar data in the Supplementary Series, as Linda
--
,))
Stela 12 Haab Patron of Mak, Wind Deity
(drawing by author after B. Fash, in Schele 1992).
FIGURE 3.
58
ARCHAEOASTRONOMY
Schele (1992:1-2) has demonstrated. As we shall
see, there is also a reference in the text on Stela 12
to the 9.10.15.0.0 Hotun completion of its Initial Series date, five Tuns prior to the K'atun ending on
9.11.0.0.0.
The Three Hearthstones
and the Orion Nebula
An analysis of the full text on Stela 12 reveals critical
information that leads to an alternative interpretation
of the function of the Copan baseline, combining hieroglyphic text, historical dates, astronomical references, and the architectural alignment found within
the baseline itself. On the north side of Stela 12 (Figure 4), we find the inscription concluding with a series of events that begins with the accession date of
K'ahk' Uti' Witz' K'awiil, then a reference to the
Initial Series date of Stela 12 as the completion of
the fifteenth Tun-the Hotun, five Tuns prior to the
K'atun ending. The ubiquitous mentioning of the
K'atun commemoration on 9.11.0.0.0, 12 Ajaw 8
Keej, follows:
12 Ajaw 8 Keej,
It was completed, the 11th K'atun.
Was witnessed his supervising (of it),
[at the] edge of the sky, First/New Three
Hearthstone Place
The text continues with the subject on the east
side, where it contains the glyph for 'cave/wellspring,' CH'EN-ni, which seems to be a metaphor
for the heart of a city, and the title 3-WINIKHAAB
ch'a-ho-ma, 'Three K'atun Incense Offerer,' followed by the name of Ruler 12. An almost exact parallel text concerning Ruler 12's observance of the
same K'atun completion appears on Copan Stela 2
with the same reading order, though it curiously
omits the reference to the Three Hearthstones that we
find on Stela 12. A known Maya asterism, the Three
Hearthstones were first identified by Barbara Ted lock
(1982:181-182) and Dennis Tedlock (1996:73) in ethnographic accounts from the K'iche' community of
Momostenango in the highlands of Guatemala. Recognized by contemporary K'iche' astronomers as the
oxib xc'ub, the Three Hearthstones form a triangular
1 WINIKHAAB
1 K'atun
FIGURE 4.
chu-[mu-wa]-ni-ya
since he was seated
ti AJAW-wa?
as Ajaw
6 CHAN
6 Chikchan
16 K'AN-a-[si]-ya
16 K'ayab
i-IL-ya
and was witnessed
??
??
ti WI'
at the lacking of
5-TUN-ni
5 Tuns
??
??
K'ALTUN-ni
Tun completion
12 AJAW
12 Ajaw
8 KEEJ
8 Keej
TZUTZ-ja
was completed
11 WINIKHAAB
11 K'atuns
i-IL-ya
and he witnessed it
u-KAB-ji-ya
he supervised it
TI'-CHAN-na
[at the] edge of sky
YAX-YOKEHT?-NAL
First/New ThreeHearthstone Place
Stela 12, north side (drawing by author from original monument on-site, and after Stuart, in Schele 1989:85).
asterism composed of three stars in Orion-Alnitak,
Saiph, and Rigel-representing the triangular configuration of the large stones that compose a common
Maya hearth. Furthermore, the K'iche' identify the
diffuse region of the Orion Nebula in the center of
this asterism as the smoke from this fire (Figure 5a).
Barbara Tedlock (1982:182) notes that even though it
has a current apparent magnitude of 4, the relatively
bright Orion Nebula curiously was not mentioned in
any European texts earlier than 1610, and some astronomers suggest that this may be the result of a
variable magnitude over time (Herczeg 1998). The
VOLUME XXV 2012-2013
59
The K'iche'
Three Hearthstones asterism, composed of Alnitak,
Saiph, and Rigel, with the
Orion Nebula as the central smoke from the hearth
fire. Na'ir al Saif appears
beneath the Orion Nebula as the "bright star of the
word." Note the distinction between the asterism of
the sword of Orion, which
resembles three vertically
aligned stars, and the more
horizontally oriented three
belt stars above it. Among
the three belt stars, only
Alnitak is considered by
the K'iche' to be one of the
Three Hearthstones (image
made using Starry Night
Pro 6.4.3 © Simulation Curriculum Corp.).
FIGURE SA.
Orion Nebula (M42) occupies the central position in
what at first appears to be another three-star asterism known as Orion's Sword-actually a collection
of nebulas and open clusters of stars, the brightest
of which is the southernmost Na'ir al Saif, meaning
"the bright star of the sword" in Arabic. In all likelihood, the nebulosity of Orion's Sword and its central
location within the Three Hearthstone asterism led
Maya observers to see this entire collection as puffs
of smoke "rising" from a celestial hearth fire.
Linda Schele and Matthew Looper subsequently
identified repeated textual references to the Three
Hearthstones in Late Classic mythological accounts
from Palenque and Quirigua (Figure 5b) associated with the mythological events that were said to
have taken place at the very beginning of the current era, at the time of the completion of a previous 13 Bak'tun cycle in the Long Count on 4 Ajaw 8
Kurnk'u (Freidel et al. 1993:79-82). As in Stela 12,
60
ARCHA EOASTRO N OMY
these text references depict the Three Hearthstones
in a triangular configuration following the glyph
YAX, which carries the meanings of 'first,' 'new,'
and 'green,' also the color representing 'center.' John
Justeson suggests that the hearthstone glyph itself
may be YOKEHT (Schele and Looper 1996:29),
and this finds further support in the common occurrence of syllabic yo- signs flanking the three stones,
also found flanking Sun and Moon signs in eclipse
glyphs.
Looper first identified this same triadic formation of three stones depicted on the back of a celestial turtle on page 71a of the Madrid Codex, while an
image of a turtle with three linear star glyphs resembling Orion's Belt appears in the Bonampak murals
(Freidel et al. 1993:79-82). Ethnographic accounts
from various Maya sources indicate that the stars
in both Orion and Gemini have been identified as a
turtle, while Orion's Belt was identified as the Az-
tee fire-drill mamalhuaztli (Milbrath 1999:266-68;
Thompson 1972:68). John Carlson initially pointed
out to Schele that this fire-drill constellation was
used to ignite the "New Fire," symbolic of a new
cycle of time (Freidel et al. 1993:81). In the Aztec Historia de los mexicanos por sus pinturas, we
find that this first fire was lit using three flint stones
in the form of three sticks "with a heart" (Garibay
1965:32-33), while in the Postclassic Yucatec Maya
Chilam Balam of Chumayel, Looper (1995:24) notes
a reference to the "three cornered precious stone of
creation" that closely parallels the creation accounts
from hieroglyphic texts.
While tentative, the hypothesis that the triadic
Three Hearthstones in Classic period Maya texts is
the same as the K'iche' asterism of the Three Hearthstones in Orion is supported by various threads of
evidence. As Schele suggests, the Maya may have
Palenque Temple of the Cross:
[a
4AJAW
4Ajaw
8 BIX-OHL-la
8 Kumk'u
CliW
13-PIK
13 Bak'tuns
JEL-ji-ya
since it was changed
..
TZUTZ-yi
completed
k'o-ba TI'-CHAN-na
the altar,* edge of the sky
YAX-YOKEHT?-NAL
First I New ThreeHearthstone Place
* See Callaway (2011 :283-286).
Quirigua Stela C:
4AJAW
4Ajaw
8 BIX-OHL-la
8 Kumk'u
JEL-la-ja k'o-ba
the altar* was changed
u-ti-ya TI'-CHAN-na
it happened [at the] edge of the sky
YAX-YOKEHT?-NAL
First I New
Three-Hearthstone
Place
TZUTZ-ya 13-PIK
completed
13 Bak'tuns
Era base events involving the Three Hearthstones (drawings by author after Linda Schele, in Schele and
Freidel 1990:Figure 6:14).
FIGURE SB.
VOLUME XXV 2012-2013
61
H
I
1
2
3
4
5
6
7
FIGURE 6. Copan Stela 23. Initial Series 9.10.18.12.8, 8 Lamat 2 Yaxk'in (should be 1 Yaxk'in) (drawing from Morley
1920:148).
E9: 8LAMAT
010: 2 YAXK'IN
EIO: u-??-K'IN-ni
Dll: 11 K'IN 5 WINIK-ki
Ell: 1 TUN (distance number of 471 days)
Ell: 12AJAW
Fl: 8 KEEJ
G7: 4AJAW
F8: 8 BIX-OHL
G8: TZUTZ-ya
F9: 13?-[PIK?].
HI: YAX-YOKEHT?-NAL
II: JEL-ja? k'o-ba.
H4: 8LAMAT
14: 2 YAXK'IN
compared the cosmos to a house on a grand scale,
and these hearthstones would therefore conceivably
represent the central hearth of a traditional Maya
home (Freidel et al. 1993:79). Given the comparable
Central Mexican mythological concept of five successive world ages, each governed by a new Sun, it is
also possible that these Maya mythological accounts
62
ARCHAEOASTRONOMY
of the Three Hearthstones involve the rebirth of the
Sun in a cosmic hearth fire at the beginning of the
current era. We may derive additional support for
this idea, given that these texts frequently describe
the historical era as following another prior age of
13 Bak'tuns, or 5,200 Tuns of 360 days each, though
there is no definitive evidence to determine whether
the Maya uniformly conceived of five such repeating
cycles of 13 Bak'tuns.
From Stela 23 in Copan (Figure 6), also part of
Ruler 12's sculpture program, we find another reference to the Three Hearthstones in association with
the era base 4 Ajaw 8 Kumk'u. Stela 23 has since
been destroyed, though Morley fortunately was
able to draw the text that was visible to him before
it was used as cement fill (Aldana 2002:37; Morley
1920:134). The two references to the Three Hearthstones in Copan are in fact the very first monumental references to this mythological asterism known
in the corpus of Maya inscriptions. Only one earlier
reference to the Three Hearthstones is found on an
undated Early Classic greenstone mask (Figure 7),
most likely from Rfo Azul, where they are again
mentioned in association with the era base 4 Ajaw
(Van Stone 2010:52-53). In all of these examples, as
well as in the later mythological texts in Palenque
and Quirigua, the Three Hearthstones are always
said to be TI'-CHAN '[at the] edge of the sky.' Furthermore, despite the prior usage of the Long Count,
which uses the shared starting point of 4 Ajaw 8
Kumk'u on the era base, Stela 23 is the first known
text to mention that the era base concluded a period of 13 Bak'tuns. This specific period ending is
FIGURE 7.
then repeated in most subsequent references to the
events that took place on the era base. Barring evidence to the contrary, it is quite possible that the
popularized concept of an earlier era of 13 Bak'tuns
in length was specifically conceived in Copan, as no
earlier evidence exists to suggest otherwise (Grofe
2011a:217, 2011b:61).
The Copan Baseline and
the Rising Orion Nebula
The reference to the Three Hearthstones on Copan
Stela 12, and the Copan baseline itself, serve as
an important test of the hypothesis that this asterism is indeed related to the contemporary K'iche'
Three Hearthstones in Orion. What is so unusual
about the example of the Three Hearthstones on
Copan Stela 12 is that it is not directly associated
with the mythological era base accounts. Instead, it
is the only such reference to the Three Hearthstones
found in association with a known historical date. In
fact, the text states that on the date of the commemoration of the K'atun ending 9.11.0.0.0, K'ahk' Uti'
Witz' K'awiil witnessed the first/new Three Hearthstones at the edge of the sky, and this prompted me
to investigate whether the Copan baseline may actually relate to the asterism of the Three Hearthstones
4 AJAW
??-ya
Tl' CHAN-na,
YAX-YOKEHT?-NAL
Undated Early Classic jade mask, era base event (drawing by author after Michael Carrasco, in Van Stone
2010:53).
VOLUME XXV 2012-2013
63
FIGU RE 8. View across the Copan Valley from Stela 10 looking ea t toward Stela 12 (tip of arrow).
in Orion literally ri ing or etting on the horizon, as
Stela 12 seems to uggest.
If we predict that the Copan ba eline was u ed to
observe either the ri ing or setting of the fairly large
Three Hearthstone asterism, it would logically follow that it specifically targeted orne part of the
Orion Nebula in the center of this asterism. Evidence
from the Postclassic K'iche' site of Utatlan suggests
that multiple temples at this site are aligned with
the setting azimuths of stars in Orion (Freidel et al.
1993:103). However, even accounting for preces ion ,
no part of the K'iche' asterism of the Three Hearthstones or even the belt tars in Orion could ever have
set on the 278° western azimuth of the Copan baseline. Conversely, might the baseline commemorate
the rising of the Hearthstones? This would require
that observations were made from the position of
Stela 10 looking east toward Stela 12, even though
Stela 12 does not appear directly on the horizon.
From Stela 10, Stela 12 appears on a hillside, at an
angle of 38' below the true horizon and less than 2°
beneath the crest of Cerro La Pintada, an approximately 1,020-m hill named for Stela 12 and the paint
still visible on its surface. Behind this hill, the visible skyline can be een on the slope of the much
higher and more distant Cerro Montenegro, a mountain in the Sierra Gallinero range (Figure 8). This
is the farthest point vi ible along the azimuth of the
•
64
ARCHAEOASTRONOMY
ba eline, and it is approximately 1,600 m in elevation and 23.7 km from Stela 10, thereby appearing
1°46' above the true horizon.
As we have seen , from the perspective of Stela 12,
Stela 10 is also not directly on the skyline, as it has
another larger hill behind it, with the skyline appearing about half a degree above Stela 10. But since
Stela 10 stands on a ridgeline, slightly higher than
Stela 12 and pointing to a position some 34' above
the true western horizon , this led Morley (1920:143)
to believe that it specifically referred to a sunset azimuth when viewed from Stela 12, and all subsequent
researchers have accepted this assumption. However,
since hills appear behind both Stela 10 and Stela 12,
is it not equally plausible that the baseline was intentionally oriented toward the eastern hori zon behind
Stela 12, especially if the baseline was used to identify a stellar alignment with the aid of a signal fire at
night? Indeed, since he could not clearly see Stela 10
from Stela 12 owing to the abundance of smoke from
burning milpas in early April , Morley (1926) lit a
large bonfire directly behind Stela 10 to create a visible marker for hi sunset observation. Baudez (1987)
contends that the need to light such a fire in order to
see what might otherwise be an invisible point of observation at this time of year renders less likely the
proposal that these monuments were even used as an
.astronomical baseline. However, the logical solution
of using a signal fire may have proved to be even
more effective for evening observations.
Believing that Stela 10 and Stela 12 referred to
positions of the planet Venus, Linda Schele (1991:4)
suggested that these monuments may have been illuminated at night by fire, much like those kept by
contemporary K'iche' on sacred mountains during
the rituals of Waxaqib Batz'. If it was illuminated
at night, Stela 12 could have been utilized as a sidereal marker for the point on the horizon directly
above it. In fact, to function for either horizon-based
stellar, planetary, or even solar observations, a fireilluminated stela placed beneath the horizon might
prove to be more useful, since a fire on the horizon
can either obscure a star or itself be obscured by the
light of the Sun. Since the visible skyline is much
farther away in the Sierra Gallinero, well beyond the
Copan Valley, positioning Stela 12 farther beneath
the skyline on a nearby hillside also enables ease of
access, while providing a functional alignment.
Again, using the same GPS coordinates I obtained for Stela 10 and Stela 12 together with the
Vincenty formula, we find that the Copan baseline
points eastward to an azimuth of 98°47'25" on the
skyline directly above Stela 12. Using either of the
GMT correlations, the K'atun ending on 9.11.0.0.0
occurred in AD 652. Due to the variable dynamics
of lunisolar and planetary precession, the azimuth
and the time of year of the rise of a given star will
change slowly over time, since the axis of the north
celestial pole slowly wobbles. This significantly alters the celestial coordinates of any given star over
time, so that the change in declination (8), equivalent to celestial latitude, will directly impact the azimuth position of a star rise; while the right ascension
(a), equivalent to celestial longitude, largely changes
the time of year and the time of the night that the
star rises.
As a preliminary test, I observed the azimuth of
98°47 ' and an altitude of 1°50' above the horizon,
simulating the vantage point of Stela 10 using Starry
Night 6.2.3 astronomical software (Simulation Curriculum Corp. 2009), and I found that in AD 652, the
Copan baseline pointed very closely to the azimuth
of the rising position of Na'ir al Saif, the brightest
star in the nebulous region of Orion's Sword in the
center of the Three Hearthstones (Figure 9). While
closer stars can show significant variation over time,
due to their unique movements relative to other stars,
in AD 652 the distant Na'ir al Saif would have risen
close to an azimuth of 98°32', at an altitude of 1°50'
above Stela 12 when viewed from Stela 10, only 15'
FIGURE 9. Reconstruction of
Na'ir al Saif rising at an azimuth of 98°32' directly
above Stela 12 as viewed
from Stela 10 in AD 652.
Stela 12 is indicated with an
asterisk to simulate illumination of the stela by fire at
an azimuth of 98°47' (image
made usi ng composite horizon photograph with Starry
Night Pro 6.4.3 © Simulation Curriculum Corp.).
VOLUME XXV 2012-2013
65
from the baseline azimuth, equivalent to half of the
width of the solar disk. The declination of Na'ir al
Saif at this time is given as -7°45'46.44". To confirm this, we can calculate the declination of Na'ir
al Saif for a precise day in history using specific formulae that incorporate precessional quantities measured from the point of January 1, AD 2000 (12000).
The declination of Na'ir al Saif for 12000 is given
as -5°54'36" (Kelley et al. 2011:57, Table 3.1), while
the declination of Na'ir al Saif for October 14, AD
652, would have been -7°46'3.5", essentially identical to that obtained by Starry Night 6.4.3 previously,
which thus provides the same azimuth position of
98°32'. 4 Therefore, the astronomical alignment of
the Copan baseline, the text on Stela 12 regarding
the observation of the Three Hearthstones, and the
year of the GMT correlations strongly support ,the
hypothesis that this asterism is related to the contemporary K'iche' Three Hearthstones and that Stela 12
served as a celestial marker for the rising point of
Na'ir al Saif as the center point of this hearth.
While both of the GMT correlations generally
support the evidence that the Copan baseline was
used to commemorate the rising of Na'ir al Saif in
the center of the Three Hearthstones, we find that
this star rose precisely at the eastern end of the baseline around AD 530, over a century prior to the
events surrounding the commemoration of K'atun
9.11.0.0.0 in AD 652. Curiously, we find that Na'ir
al Saif continues to rise close to this same azimuth
of 98°48 ' for several hundred years during the Classic period, because of the properties of precessional
dynamics for stars with celestial longitudes close to
those of the solstices. The azimuth rising positions
of stars close to six hours of right ascension shift
much more slowly over time than those closer to the
zero point of right ascension where we find the vernal equinox. As a result, the azimuth of the rising
point of Na'ir al Saif shifted less than a quarter of a
degree per century before and after AD 652. Therefore, the use of the Copan baseline as a celestial
marker for the rising point of Na'ir al Saif, as well as
the adjacent Orion Nebula, would remain quite stable and would have functioned properly for the remaining duration of Copan's history until the early
ninth century, when its rising azimuth shifted north
66
ARCHAEOASTRONOMY
by only half a degree, the observable width of the
solar disk.
The Sunrise on 9.11.0.0.0 and the Copim Baseline
Beyond the apparent baseline alignment to the Three
Hearthstones itself, there appears to be another important rationale for why this asterism is mentioned
in association with the K'atun ending 9.11.0.0.0 on
Stela 12, and this evidence also supports the use
of one of the GMT calendar correlations. Employing a Gregorian proleptic calendar akin to our own
tropical-year positions, we find that the 584285 GMT
correlation constant places 9.11.0.0.0 on October 14,
AD 652 (October 11, Julian). On this date, we find
that the first light of the Sun rose just 16' south of
the baseline, equivalent to half the width of the solar
disk at an azimuth of 99°3' and an altitude of 1°50 ',
essentially matching the rising position of Na'ir al
Saif in the Three Hearthstones (Figure 10). Therefore, it is possible that the Copan baseline commemorated the position of the rising Sun on the date of
the completion of the eleventh K'atun. In this way,
it appears that K'ahk' Uti' Witz' K'awiil was linking himself and the sunrise on K'atun 9.11.0.0.0 to
the center of the Three Hearthstones as the mythological hearth fire, perhaps from which the Sun itself
was thought to have emerged at the beginning of the
current era on 4 Ajaw 8 K'umk'u.
If the Copan baseline was designed to associate
both the rising point of Na'ir al Saif in the Three
Hearthstones and the sunrise on 9.11.0.0.0, which
appears to be the case, this is a very strong argument for the use of the 584285 GMT correlation
in this specific time and place. In the decades surrounding AD 652, it is significant that the azimuth
of the sunrise on the baseline varied between October 13 and 14, where it continues to appear at present. However, the Sun never rose behind the baseline
on October 12, which would be the date of 9.11.0.0.0
using the alternative 584283 GMT correlation constant. Likewise, the more recently proposed 584286
correlation (Martin and Skidmore 2012) places this
date on October 15, one day after the baseline azimuth. While not definitive proof, the evidence supports the validity of the use of the 584285 GMT
correlation, at least in Copan during this time in the
FIGURE 10. Reconstruction
of sunrise at an azimuth of
99°3' directly above Stela
12 as viewed from Stela
10 on 9.11.0.0.0, 12 Ajaw 8
Keh, October 14, AD 652
(October 11, Julian), using
the 584285 GMT correlation constant. Stela 12 is indicated with an asterisk to
imulate illumination of the
tela by fire at an azimuth of
98°47' (image made using
composite horizon photograph with Starry ight Pro
6.4.3 © Simulation Curriculum Corp.).
Cla ic period. For the ake of argument, and to facilitate a clearer presentation, I will hereafter use
only the 584285 GMT correlation within this discussion, although this doe not discount the possibility
of the accuracy of the 584283 GMT or the 584286
correlation both in Copan and elsewhere, since we
cannot assume that the Long Count remained unchanged in all times and places. In fact, as Aldana
(2002:39) notes, it appears that Ruler 12 himself recorded several nonstandard Calendar Round dates
that shift the Haab position forward by one day on
Stela 2, Stela 3, and Stela 23. Contrary examples of
Haab dates shifted backward by one day have been
used to support the idea that these may have been
evening observations if the Tzolk'in changes at sunset before the Haab at sunrise (Martin and Skidmore
2012; Mathews 2001 [1979]; Stuart 2004), but these
Copan dates do not conform to this pattern.
Sidereal Measurements Using
Na 'ir a/ Saif and the Orion Nebula
Na'ir al Saif rises at the eastern end of the Copan
baseline, but might such an observation have been
made of its heliacal rise when it becomes first visible
at dawn? During the Classic period, the hel iacal rise
of Na'ir al Saif would have occurred in mid-June.
Using either of the two GMT correlations, we curiously do not find any significant position for a'ir
al Saif for either the Initial Series date on Stela 12
of 9.10.15.0.0, 6 Ajaw13 Mak, on November 10, AD
648 (November 7, Julian), or for the K'atun ending
9.11.0.0.0, 12 Ajaw 8 Keej, on October 14, AD 652
(October 11, Julian). If either one of the GMT correlations is correct, these period ending dates do not
appear to have been used for the observation of the
first visibility of Na'ir al Saif. On the other hand, if
we take the inscription on Stela 12 to literally refer to
the first visibility of Na'ir al Saif on 9.11.0.0.0, then
both of the GMT correlations would be incorrect,
and the possibility remains open to explore an alternative correlation that reconciles this interpretation.
Yet, as we have found, 9.11.0.0.0 does corre pond to
the sunrise on the eastern end of the Copan baseline using the 584285 GMT correlation, while this
same azimuth identifies the rising point of Na'ir al
Saif, and this suggests that K'ahk' Uti' Witz' K'awiil
intentionally compared the sunrise on the 9.11.0.0.0
K'atun ending with the rising point of the center of
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67
Reconstruction
of the first visibility of Na'ir
al Saif and the Orion Nebula rising directly above
Stela 12 as viewed from
Stela 10 on 9.10.18.12.8,
June 30, AD 651 (June 27,
Julian), using the 584285
GMT correlation constant.
Stela 12 is indicated with an
asterisk to simulate illumination of the stela by fire at
an azimuth of 98°47' (image
made using composite horizon photograph with Starry
Night Pro 6.4.3 © Simulation Curriculum Corp.).
FIGURE 11.
the Three Hearthstones. Given the predominant evidence for the GMT correlations, I take this as the
more likely explanation.
While the 9.11.0.0.0 K'atun ending does not appear to correspond to the first visibility of Na'ir al
Saif using either of the GMT correlations, Stela 10
and Stela 23 present themselves as possible candidates. As the point of observation of the baseline
looking east, Stela 10 gives the unusual Initial Series
date of 9.10.19.13.00, 3 Ajaw 8 Yaxk'in, July 6, AD
652 (July 3, Julian). Non-period-ending dates such as
this suggest that this specific date was chosen for another purpose. With an apparent magnitude of 2.76,
Na'ir al Saif would have been first visible on the horizon about two weeks earlier. However, this later
date may correspond to the time of the first visibility
of the Orion Nebula immediately adjacent to Na'ir
al Saif, behind Stela 12 prior to dawn when the Sun
was 20° below the horizon toward the end of astronomical twilight (see Figure 9). At this time, depending on clarity, the sky would still be at its darkest,
allowing for horizon observations of fainter stars.
By first observing the heliacal rise of Na'ir al Saif,
observers may have been able to track and predict
the first appearance of the Orion Nebula on the horizon at dawn as the visible "smoke" from the Three
Hearthstones.
, 68
ARCHAEOASTRONOMY
The actual date of the expected heliacal rise of
the Orion Nebula would more likely have occurred
a week or so earlier, when the Sun was within 12o16° below the horizon during nautical twilight,
when magnitude 4 objects such as the Orion Nebula are still visible. However, the age of the Moon
on Stela 10 is given as 21 days since new, so it is
possible that the brightness of the Moon interfered
with the observation of first visibility, as it was still
visible at sunrise. Aveni (2001:255) notes that a visible lunar eclipse occurred several days prior to the
Initial Series date on Stela 10, on June 29, AD 652
(June 26, Julian), while Stela 10 then records the
first Ajaw day following this event, which may have
also provided another important significance for this
date, since Ajaw is used as the standardized whole
multiple of the vigesimal-based system. This eclipse
was perhaps all the more notable given that the lunar nodes were positioned at the point of the two
solstices at the time-a phenomenon that recurs approximately every nine years. We will return to further investigate additional references within the text
from Stela 10.
On Stela 23, which is the second monumental text to prominently feature the Three Hearthstones, we also find an unusual Initial Series date
9.10.18.12.8, on June 30, AD 651 (June 27, Julian),
that corresponds to the same time of year as the date
on Stela 10, only six days earlier in the tropical year,
which may have coincided with the date of the first
visibility of the Orion Nebula when the Sun was 15°
below the horizon at nautical twilight (Figure 11).
Therefore, it is possible that the two non-periodending dates on Stela 23 and Stela 10 were used to
record the first visibility of the Orion Nebula in association with Na'ir al Saif behind Stela 12 on the
Copan baseline.
Using the Tzolk'in and the K'atun
to Calculate the Metonic Cycle
Helen Alexander (1988:47) noted the appearance
of pairs of dates separated by 260 days among the
monuments in Copan. She found that one of the Initial Series dates on Ruler 12's Stela 3 occurred on
9.10.19.5.0, exactly 260 days prior to the period ending on 9.11.0.0.0. Alexander compared this to another pair of dates mentioned on Copan Stela A,
a monument commissioned by the later Ruler 13,
Waxaklajuun Ubaah K'awiil. Similarly, one date on
Stela A, 9.14.19.5.0, falls exactly 260 days prior to
the period ending on 9.15.0.0.0, also mentioned in
this text. Alexander suggested that these intervals
relate to positions of Venus at superior conjunction,
while she also found that both of the texts on Stela 3
and Stela A posthumously refer to Ruler 11, whose
full name is given as K'ahk' Uti' Chan Yopaat,
though he was previously nicknamed "Butz' Chan"
(Grube and Martin 2000:200). Yet there are additional paired dates separated by 260 days in Copan,
and they do not all seem to relate to Venus. After
confirming the Initial Series date on Copan Stela 12
as 9.10.15.0.0, Schele (1992) subsequently noted that
Stela 2, another of Ruler 12's monuments, gives a
date 260 days later as 9.10.15.13.0. Moreover, both
Stela 12 and Stela 2 contain a great deal of parallel
text, but they do not conform to Alexander's Venus
positions, and they contain no obvious references to
Butz' Chan.
John Teeple (1930:71) noticed that Stela A in
Copan contains the date 9.14.19.5.0, which is not
only 260 days prior to the K'atun ending 9.15.0.0.0;
it is also exactly 6,940 days after the previous K'atun
ending on 9.14.0.0.0. This is a Metonic cycle, which
can be used to commensurate an interval of 19 tropical years with 235 lunations. Significantly, Stela A
appears in the Great Plaza very close to Stela C, another of Waxaklajuun Ubaah K'awiil's monuments,
with the date 9.14.0.0.0 for comparison. In effect,
the position of the tropical year and the phase of the
Moon-significantly, the full Moon-are equivalent
on 9.14.0.0.0 and 9.14.19.5.0, and Teeple suggests that
this Metonic cycle was surely noticed and intentionally recorded.
Metonic cycles were evidently calculated on both
K'atun and Hotun endings. As Schele found on
Stela 2, we find the date 9.10.15.13.0, July 27, AD 648
(July 24, Julian). This is 260 days after the Hotun
date on Stela 12, 9.10.15.0.0, and it would also be one
Metonic cycle prior to the Hotun on 9.11.15.0.0, exactly one K'atun after the date on Stela 12. Indeed,
K'ahk' Uti' Witz' K'awiil commemorated this later
date on the south side of Stela 5.
Combined with the 260-day Tzolk'in, the K'atun
could be used to calculate the tropical-year position
and the phase of the Moon and to predict exactly
where the Sun will rise on future K'atuns. We can
now examine how K'ahk' Uti' Witz' K'awiil may
have utilized the Metonic cycle to calculate positions
in the tropical year and lunar phases over multiple
K'atuns, and how he may have utilized the Copan
baseline as a means of predicting and celebrating the
K'atun ending 9.11.0.0.0, when the Sun rose at the
same azimuth as Na'ir al Saif in the Three Hearthstones. Ruler 12's monuments evidently contain multiple such Metonic K'atun predictions within a host
of other specific calculations of the tropical year. Table 1 provides an inventory of these monuments and
their associated dates.
Metonic Cycles and the Death of Butz'
Chan: The Symbolic Tropical Year
Alexander (1988) noted that the east side of Ruler 12's
Stela 3 records the date 9.10.19.5.0, January 28,
AD 652 (January 25, Julian), exactly 260 days prior
to the K'atun ending on 9.11.0.0.0. Associated with
this date on Stela 3, we find the name of Ruler 12's
predecessor, Butz' Chan. This date is also one Metonic cycle after the previous K'atun ending on
9.10.0.0.0, January 27, AD 633 (January 24, Julian),
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69
Table 1. The Monuments of Copan Ruler 12 (GMT 584285)
StelaE
9.5.0.0.0, 11 Ajaw 18 Sek
July 5, 534 (July 3, J)
Commemoration of K'atun
Sun in identical sidereal position as Stela 10:
9.10.19.13.0, July 6, 652 (July 3, J)
StelaE
9.5.18.10.0, 9 Ajaw 8 Sak
Oct. 18, 552 (Oct. 16, J)
Blackened Ajaw, four days before lunar eclipse
260 days before July 5, date of 9.5.0.0.0
Sun in identical position as it was on 9.4.0.0.0
Stela 5
9.9.14.17.5, 6 Chikchan 18 K'ayab
Feb.8,628(Feb.5,J)
Accession of Ruler 12 (also mentioned on Stela 2 and Stela 12),
solar nadir
Stela 12
9.10.15.0.0, 6 Ajaw 13 Mak
Nov. 10, 647 (Nov. 7, J)
Commemoration of the Hotun
Stela 2
9.10.15.13.0, 6 Ajaw 8(9) Mol
..,
July 27-28, 648 (July 24-25, J)
Metonic: 260 days after 9.10.15.0.0
Sun in identical position as on Stela 5: 9.11.15.0.0
Stela 23
9.10.18.12.8, 8 Lamat 1(2) Yaxk'in
June 30/July 1, 651 (June 27-28, J)
260 days after Oct. 14, date of 9.11.0.0.0 K'atun
Sun in identical position as it will be on 9.12.0.0.0
First visibility of Orion Nebula
Stela 3e
9.10.19.5.0, 12 Ajaw 13(14) K'ayab
Jan.28-29,652(Jan.25-26,J)
Metonic: 260 days before 9.11.0.0.0, Stela 13
Sun in identical position as it was on K'atun 9.10.0.0.0
This date also mentioned in Stela 10, with a blackened AJAW
Stela 3w
9.10.19.5.10, 9 Ok 3(4) Kumk'u
Feb.7-8,652(Feb.4-5,J)
Sun in identical position as it was on accession (Stela 5), solar
nadir
Stela 10
9.10.19.13.0, 3 Ajaw 8 Yaxk'in
July 6, 652 (July 3, J)
Lunar eclipse 6 days earlier, nodes exactly at the solstices
Exactly the same solar sidereal as Stela E: 9.5.0.0.0 11, July 5,
534 (July 3, J)
Blackened Ajaw 160 days earlier on 9.10.19.5.0 (Stela 3e)
Stela 19
9.10.19.15.0, 4 Ajaw 8 Ch'en
Aug. 15, 652 (Aug. 12, J)
Solar zenith on Aug. 13 related to 4 Ajaw 8 Kumk'u era base
date?
Stela 13
9.11.0.0.0, 12 Ajaw 8 Keej
Oct. 14, 652 (Oct. 11, J)
Sun rises on Copan baseline, same position as Orion Nebula
Commemoration of K'atun, mentioned on Stelae 2, 3, 10, and 12
Stela 5
9.11.15.0.0, 4 Ajaw 13 Mol
Commemoration of the Hotun
Sun in identical position as on Stela 2: 9.10.15.13.0
July 28, 667 (July 25, J)
90K
90k
SIH-ya-ja
Was born
4BIXOHL
4 Kumk'u
YAXCHIT
First Companion/Father
la?-ma-ja
is submerged?
[Title of Ruler 12]
CH'ICH'-BAAK
Blood and bones
K'AHK-TI'-WITZ'-K'AWIIL
[Ruler 12]
Copan Stela 3
west (photograph by author).
FIGURE 12A.
which would have been the first K'atun ending during Ruler 12's reign. Significantly, on the west side of
Stela 3, we find a date 10 days after the date on the
east side, on 9.10.19.5.10, February 9, AD 652 (February 6, Julian). The text curiously refers to a (re)birth
event involving blood and bones and what appears
to be the conjured spirit of Butz' Chan, identified by
the recognizable title YAX-CHIT (Figure 12a), here
with the rabbit-head form of CHIT (T759) that substitutes for the more common form (T580).
Following the initial reading of T580 as CHIT
(Stuart et al. 1999:56), Barbara MacLeod translates
this term as a cognate of the Yucatec ke:t as 'one
of a pair' and 'companion,' while Sven Gronemeyer
reads it as 'patron god,' following a suggestion by
Pierre Colas (Gronemeyer and MacLeod 2010:13).
The term chit also appears in many male parentage statements. However, MacLeod identifies the
use of this term in a rare female parentage statement, suggesting that it refers to 'her co-creation'
(Gronemeyer and MacLeod 2010:53). As 'first companion/pair,' yax chit is an interesting title that often appears in the name of so-called vision serpents
involved in conjuring the spirits of departed ancestors. In the context of Maya conjuring in Copan, it
would seem that the kings pair themselves with their
departed ancestors as their "first companions." In
so doing, they may provide a means for the spirit of
their ancestors to be reborn in their bodies, thereby
paralleling the archetype of the Maize God, who
dies and is reborn with the help of his own children,
the Hero Twins (Taube 1985).
Aldana (2002:39) noticed that the date 9.10.19.5.10
on Stela 3 is a tropical-year anniversary of the accession of Ruler 12, precisely 24 years (3 synodic cycles
of Venus) earlier on 9.9.14.17.5, February 8, AD 628
(February 5, Julian), as stated on the west side of
Stela 2, the north side of Stela 12, and the south side
of,Stela 5. Here on Stela 3, associated on one monument, it seems that K'ahk' Uti' Witz' K'awiil was
intentionally measuring the tropical-year anniversary of his accession, as well as one Metonic cycle
following his first K'atun ending on 9.10.0.0.0. Curiously, we find that his accession occurs precisely
on the February 8-9 solar nadir, or the anti-zenith
at Copan, and such an intentionally chosen date appears to have served as an important anchor in the
tropical year. Indeed, the date of the solar nadir at
Copan's latitude of 14.8° N was used repeatedly in
Copan, as well as at various sites at a number of different latitudes during the Classic and Postclassic
periods (Grofe 2011a, 2011b:225-226).
I propose that the reference to Butz' Chan on
the east side of Stela 3, in association with the date
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71
K'AHK' Tl' CHAN
ma[m]-AJAW-wa
9-i-pi-la-ja
BAAK-CH'ICH'
Butz Chan' [Ruler 11]
Grandfather? Lord
many times strengthened
bones and blood
K'IN-ni su-sa-ja
ba-ki u-CHAM-ya-li
[of] the Sun. Were cut
bones of the dead
OCH-bi-ji
u-me-k'e-ji-ya
the banner stone
u la-ka-ma TUN-ni
Entered the road [died].
He had embraced
u-bah AN-nu K'AHK'
TI'?-K'IN CHAN-na
YAX CHIT-ta
ta-o-CHIT-ta NAH-K'UH
He impersonates
[sqlar? Ruledl]
First Companion/Father
at the Companion God House place?
18-b'a K'AWIIL-la
K'UH [BAT]-piAJAW-wa ba-ka-ba
18 Ubaah K'awiil [Ruler 13]
Holy Copan Lord, Bakab
FIGURE 12B.
Copan Stela A west (drawing by author after Schele 2000:Number 1003).
9.10.19.5.0, January 26, AD 652 (January 23, Julian),
most likely derives from a close proximity to the
tropical-year anniversary of the date of his death,
which was recorded on Step 8 of the Copan Hieroglyphic Stairway as 9.9.14.16.9, January 21, AD 628
(January 18, Julian). Sixteen days after the death of
Butz' Chan, K'ahk' Uti' Witz' K'awiil acceded as
Ruler 12. Thus, on Stela 3, Ruler 12 appears to be
commemorating the death of his predecessor, along
with the anniversaries of both his own accession and
his first K'atun in office on 9.10.0.0.0.
Similarly, as Alexander found, Waxaklajuun
Ubaah K'awiil, the successor to Ruler 12, also directly refers to Butz' Chan on Stela A, twice mentioning his name, including the same title found on
Stela 3, YAX-CHIT. Rather than its being a result
from the Metonic calculation mentioned on Stela A,
I propose that this reference appears because the Initial Series date of Stela A, 9.14.19.8.0, February 3,
AD 731 (January 30, Julian), is also close to the
tropical-year anniversary of the death of Butz' Chan,
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much as we find in Stela 3. Furthermore, the text
on Stela A (Figure 12b) directly mentions the death
of Butz' Chan twice, along with the "strengthening
of the blood and bones of the sun" compared with
some kind of ritual or symbolic exhumation and cutting or "scraping of the bones of his deceased" (Biro
and Reents-Budet 2010; MacLeod, personal communication 2014) that seems to parallel the events
mentioned on Stela 3, though here we are told that
Waxaklajuun Ubaah K'awiil commemorates this
event by impersonating Butz' Chan himself as the
Maize God. These repeating commemorations of
the death of Butz' Chan make sense, given that they
occur very close to the tropical-year anniversary of
his death. Thus, these observed anniversaries provide a significant insight into the ritual importance
of the tropical year, suggesting the symbolic parallel
of the yearly rebirth of the Sun and maize with the
death and rebirth of ancestral kings.
Stela A also contains the Metonic calculation that
Teeple (1930:71) first noted, but this is actually a ref-
erence to the commemoration of the nearby Stela H,
60 days earlier on 9.14.19.5.0, December 5, AD 730
(December 1, Julian). Here, Waxaklajuun Ubaah
K'awiil is depicted impersonating his grandfather as
the Precious Maize God-the very symbol of agricultural rebirth itself. Stela H thus repeats the same
position of the Sun and full Moon that occurred
one Metonic cycle earlier on the adjacent Stela C,
on 9.14.0.0.0, December 5, AD 711 (December 1,
Julian). On both of these dates, the Sun was (invisibly) in conjunction with the center of the widest part
of the Milky Way between Sagittarius and Scorpio,
while, significantly, the full Moon appeared at the
opposite position in the Milky Way near Orion.
The Copan Baseline and the Metonic Cycle
The text of Stela 10, the western monument on the
Copan baseline, counts back 160 days to the Metonic
interval from the east side of Stela 3, 9.10.19.5.0, January 28, AD 652 (January 25, Julian). This date
is exactly 260 days prior to the K'atun ending on
9.11.0.0.0, and it also would have been the tropicalyear position of the previous K'atun on 9.10.0.0.0.
Given that the Copan baseline marks the precise position of the sunrise on 9.11.0.0.0 as viewed from
Stela 10, it would have been relatively straightforward to predict this position by observing the
sunrise azimuth 260 days after K'atun 9.10.0.0.0,
here commemorated one Metonic cycle later on both
Stela 3 and Stela 10.
Similarly, we might expect to find predictions
for the following K'atun on 9.12.0.0.0. In fact, on
the unusual date from Stela 23 of 9.10.18.12.8,
June 30, AD 651 (June 27, Julian), we find that the
tropical-year position of this date is equivalent to
the same position exactly 260 days after K'atun
9.11.0.0.0. This suggests that, even though it was
dedicated over one year prior to the K'atun ending
on 9.11.0.0.0, Stela 23 may have predicted the tropical-year position of the following K'atun ending on
9.12.0.0.0, July 1, AD 672 (June 28, Julian). Like the
24-tropical-year anniversary of Ruler 12, this prediction suggests a break from the strict Metonic cycle,
and it is likely that this particular date was chosen
for other reasons. As we have seen, the date on Stela
23 may have coincided with the first heliacal appear-
ance of the Orion Nebula and Na'ir al Saif rising r
the eastern end of the Copan baseline. Therefore.
Stela 23 may have also predicted that this central
star in the Three Hearthstones would become first
visible on the precise date of the K'atun ending on
9.12.0.0.0, exactly 21 tropical years later.
Solar, Lunar, and Eclipse Intervals
The unusual date on Stela 23 may also be the result
of recording lunar information. The Metonic cycle
is also only 7.6 days longer than 20 eclipse years of
346.62 days. Therefore, one Metonic cycle can predict a repeating eclipse on the same day of the tropical year, precisely 19 tropical years later. However,
this eclipse interval breaks down after three successive Metonic cycles, and a more refined measurement is necessary over longer periods of time.
A further analysis of the date on Stela 23 demonstrates that it coincides with the day on which the
Sun crosses a lunar node. Though an invisible lunar
eclipse occurred 11 days after this date on July 11,
AD 651 (July 8, Julian), it is possible that the Maya
were closely tracking and predicting the eclipse year
and the eclipse half-year, as I have proposed elsewhere (Grofe 2007:140-150, 212-219). Further support for the proposal that the Maya were capable of
tracking these intervals is evident in the recently
excavated astronomical inscriptions from Xultun
(Bricker et al. 2014:162).
Although K'atun endings rarely coincide with
eclipse events, the intervals between specific eclipses
and K'atun endings could have been recorded to facilitate the prediction of eclipses in future K'atuns.
This is precisely what the unusual non-periodending date on Stela 10 suggests, on 9.10.19.13.0,
July 6, AD 652 (July 3, Julian), since a lunar eclipse
occurred just six days prior to this date, as noted
by Aveni (2001:255). Here, it is interesting that the
tropical-year position of this lunar eclipse is within
one day of the tropical-year position of both Stela 23
and the future K'atun ending on 9.12.0.0.0. Furthermore, the lunar nodes on this date are located precisely in the sidereal position of the two solstices,
and this may have been of interest to astronomers
seeking to anchor eclipse events to positions in the
tropical year.
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(a)
(b)
FIGURE 13: Blackened AJAW in Ruler 12's monuments. (a) Detail from CPN StelaE: 9.5.18.10.0, 9 Ajaw 8 Sak (drawing
by author after Schele 2000:Number 1007). (b) Detail from CPN Stela 10, Gl-H2 (drawing by author after Barbara Fash,
in Schele 1989:34).
It appears that the measurements of Metonic cycles were particularly associated with K'atun endings and associated eclipse events, despite their rare
co-occurrence. The Metonic cycle is thus quite useful and easy to use together with the cycle of K'atuns
for the purposes of tracking the tropical year, the lunar cycle, and eclipses.
Stela E and the Blackened Ajaw Dates
Stela E in Copan can be found on the western edge
of the Great Plaza. While its text is difficult to read,
StelaE was apparently dedicated by Ruler 12 (Grube
and Martin 2000:197, 201). The text on StelaE appears to describe events in the life of the much earlier Ruler 7, Bahlam Nen, with the Initial Series
corresponding to 9.5.18.10.0, October 19, AD 552
(October 16, Julian). The Calendar Round date corresponds to 9 Ajaw 8 Sak, and the face of the Ajaw
glyph is unusually darkened with cross-hatching
(Figure 13a). Interestingly, we find the very same
type of blackened Ajaw glyph on Stela 10 (Figure 13b), corresponding to the Metonic interval
found on Stela 3, 9.10.19.5.0, January 28, AD 652
(January 25, Julian), 260 days prior to the K'atun
• 74
ARCHAEOASTRONOMY
ending on 9.11.0.0.0 and equivalent to the same
tropical-year position as the previous K'atun ending
on 9.10.0.0.0.
The second date mentioned on Stela E is the previous K'atun ending 9.5.0.0.0, 11 Ajaw 18 Sek,
July 5, AD 534 (July 3, Julian). It is fascinating that
this is exactly the same sidereal position of the Sun
that we find in the Initial Series date from Stela 10,
on 9.10.19.13.0, 3 Ajaw 8 Yaxk'in, July 6, AD 652
(July 3, Julian), while the tropical year has shifted
nearly two days due to precession in the intervening 118 years. This type of paired sidereal positions of the Sun is quite interesting, and such paired
dates suggest intentional calculations of the sidereal
year. Given the unusual non-period-ending date on
Stela 10, and the fact that Stela 10 and Stela E were
both commissioned by Ruler 12, it is possible that
Ruler 12 was using Stela 10 to commemorate the
sidereal-year anniversary of the K'atun ending on
9.5.0.0.0, nearly six K'atuns earlier during the reign
of Bahlam Nehn. Recalling that the Initial Series
date on Stela 10 fell close to the time of the first visibility of the Orion Nebula in association with Na'ir
al Saif on the Copan baseline, it is conceivable that
these observations were used to calculate the sidereal year and that the slowly accumulating difference between the sidereal year and the tropical year
was noticeable, using data collected over hundreds
of years. Perhaps significantly, in AD 534, the retrospective year of K'atun 9.5.0.0.0 referenced on Stela
E, Na'ir al Saif itself would have risen exactly above
the eastern azimuth of the Copan baseline, suggesting that the preliminary observations for the baseline itself may have first originated at this early date.
The sidereal year is an independent measurement, separate from the rate of the precession of the
equinoxes, which changes slowly with the variable
length of the tropical year. Nevertheless, comparing the accumulated difference between a calculated
tropical-year value and the sidereal year yields a calculation for precessional drift. The sidereal year of
approximately 365.25636 days remains quite constant over thousands of years, reflecting the orbital
period of the Earth relative to the stars (Capitaine
et al. 2003). Therefore, I maintain that it is possible to find supporting evidence for the intentionality of sidereal-year calculations by the presence of
paired dates on either a single text or related texts
that place the Sun in approximately the same sidereal position over intervals greater than 100 years in
length (Grofe 2011b). These shorter intervals then
can be compared with longer deep-time intervals,
often in the same texts, to determine if they also provide whole multiples of the resulting sidereal-year
value, as calculated by the Maya. Evidence for sidereal-year calculations can be found in deep-time intervals from Palenque and multiple other sites in the
Classic period. These texts include Naranjo Altar 1,
Tikal Stela 10, Tortuguero Monument 6, and Copan
Stela J, each of which I have described and analyzed
(Grofe 2011a, 2011b).
Elsewhere (Grofe 2007, 2011b), I have demonstrated that several deep-time intervals in the
Dresden Codex appear to correspond to precise calculations of the sidereal year, placing the Sun in the
same sidereal position over thousands of years using a sidereal-year value very similar to the currently measured interval. In addition, both Barbara
MacLeod (2008) and I (2003) independently noticed
that the 3-11 Pik interval of 25,980 days, mentioned
in multiple texts throughout the Classic period,
closely corresponds to one day of precessional drift
between the sidereal year and the tropical year. Calculations of the sidereal year may have been facilitated by the use of celestial star risings, such as the
first appearance of Na'ir al Saif or the Orion Nebula, in tandem with specific days in the tropical year.
Therefore, long-term usage of the Copan baseline
could have enabled precise measurements of the sidereal year.
Additionally, the blackened Ajaw Initial Series date from Stela E, on 9.5.18.10.0, October 19,
AD 552 (October 16, Julian), is exactly equivalent
to a tropical-year position 260 days earlier from
the tropical-year position of the K'atun ending on
9.5.0.0.0. This implies yet another commemoration of the tropical-year anniversary of the previous
K'atun ending on 9.4.0.0.0, October 16, AD 514 (October 14, Julian). While it is not a Metonic cycle, the
interval between 9.5.0.0.0 and 9.5.18.10.0 is exactly
260 days less than a Metonic cycle, and this specific
date may have been chosen due to both its being a
tropical-year anniversary of the earlier K'atun and its
proximity to a partial lunar eclipse, which occurred
four days after the Initial Series date of Stela E, on
October 22, AD 552 (October 20, Julian). Similarly,
Stela 23 coordinates a non-Metonic pre-anniversary
prediction of the K'atun ending on 9.12.0.0.0, while
also placing the Sun at a lunar eclipse node. It is
tempting to suggest that the blackened Ajaw on
Stela E refers to this lunar eclipse coordinated with
the Metonic cycle, whereas the blackened Ajaw on
Stela 10 similarly coordinates another lunar eclipse
with the Metonic cycle. The blackened Ajaw dates
on Stela 10 and Stela E both reference a tropical-year
position 260 days prior to a K'atun ending, equivalent to the tropical-year position of the previous
K'atun. Since K'ahk' Uti' Witz' K'awiil dedicated
both Stela E and Stela 10, it appears that he was
also calculating lunar eclipse cycles using data that
spanned multiple centuries.
Conclusion: Stela 19, the Solar Zenith,
and the Era Base of the long Count
Finally, in his extensive commemoration of the
K'atun ending on 9.11.0.0.0, K'ahk' Uti' Witz'
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75
K'awiil erected Stela 19 and Stela 13 at the extreme
western and eastern boundaries of the Copan Valley.
In the northeast, Stela 13 is the last of the valley stelae, with the Initial Series of the K'atun ending itself
on 12 Ajaw 8 Keej, October 14, AD 652 (October 11,
Julian). Located in a small valley to the west of Stela
10, Stela 19 is curiously nearly aligned on the baseline, but apparently not visible from Stela 10. However, an observer high on the hill to the west of
Stela 19 conceivably would be able to view an illuminated Stela 19 aligned with Stela 10. In the far
distance, it would be possible to see Stela 12 behind
Stela 10 from this same vantage point.
Using the 584285 GMT correlation, Stela 19
gives an Initial Series date of 9.10.19.15.00, 4 Ajaw
8 Ch'en, August 15, AD 652 (August 12, Julian). As
we have seen, non-period-ending dates such as this
may, on further examination, encode intentional astronomical information. In this case, Stela 19's date
falls just two days after the August 13 solar zenith
in Copan, perhaps serving as an important anchor
in the tropical year only 60 days prior to the K'atun
ending. The alternative 584283 GMT correlation
would place the date of Stela 19 exactly on this August 13 solar zenith, possibly suggesting contrary
evidence for this correlation. Indeed, if the 584285
GMT correlation was being used here in Copan in
AD 652, as the baseline azimuth suggests, it is unclear why Stela 19 would not have been placed two
days earlier on the exact date of the solar zenith.
While precise observations of the zenith can be difficult to measure directly with great specificity, the
Ajaw date on Stela 19 may have been of primary importance. As the first Ajaw date following two days
after the zenith, this pattern would seem to parallel
what Aveni (2001:255) proposed for Stela 10, which
commemorates the first Ajaw date six days after a
lunar eclipse.
The 584285 GMT correlation constant takes its
name from Julian Day Number 584285, which curiously places the back-calculated era base of the
Long Count, 4 Ajaw 8 Kumk'u, on August 13, 3114
BC (September 8, Julian), the same date of the solar zenith in Copan. Whether placing the era base
on the August 13 zenith was an intentional calculation of the originators of the Long Count is diffi• 76
ARCHAEOASTRONOMY
cult to prove, though several scholars have suggested
that the Long· Count was invented at the latitude of
Copan at 14.8° N for the very reason that the era base
is identical to the second solar zenith at this latitude,
using the 584285 GMT correlation. In addition, the
two solar zeniths at this particular latitude are precisely 260 days apart-another fortuitous harmony
with the pan-Mesoamerican Tzolk'in, suggesting either a great coincidence or an intentional calculation.
Vincent Malmstrom (1997:104, 179) has also noted
multiple building alignments to the August 13 (Gregorian) sunset throughout Mesoamerica, including
Chichen Itza, Teotihuacan, and Tikal. Most of these
sites are far north of 14.8° N latitude; therefore, the
days on which their local solar zenith passages occur are not equivalent to those in Copan. Nevertheless, it appears that the two dates of August 13 and
April 30/May 1 were recognized throughout Mesoamerica. Ivan Sprajc (2000, 2009) has since demonstrated that these same architectural alignments to
the sunset on these two days are common in Central Mexico, along with the corresponding sunrises
on February 12 and October 30, precisely half a
year from the August 13 and April 30/May 1 positions. Multiple Early Classic sites in the Maya Lowlands of southeastern Campeche appear to focus on
these same sunrises on February 12 and October 30,
suggesting that they have been observed throughout
Mesoamerica for some time, splitting the year into
fixed agricultural periods of 260 days and 105 days.
If we use the alternative 584283 GMT correlation,
the era base would have fallen two days earlier on
August 11, 3114 BC (September 6, Julian). Nevertheless, if the 584283 correlation was used at the time
the Long Count was inaugurated, and if the August 13 zenith was intentionally targeted, a two-day
error is certainly within the realm of possibility or
even probability among early astronomers endeavoring to back-calculate dates thousands of years in the
past. However, without additional evidence, it is difficult to firmly establish the possible intentions of the
creators of the Long Count, and we are left to speculate regarding the specificity of the era base date, albeit with great interest.
If the originators of the Long Count intended to
back-calculate the era base on the August 13 so-
lar zenith at the latitude of Copan, then this would
have required quite an accurate measurement of the
length of the tropical year as early as the first century BC, at the time of the earliest evidence for the
use of the Long Count. Certainly, the unique phenomenon of the zenith passage in tropical latitudes
could fortuitously enable some degree of accuracy
in such measurements, and it is possible that Mesoamerican peoples noted and recorded these measurements quite early. Furthermore, ethnographic
evidence demonstrates that Maya peoples continue
to recognize the two solar zeniths (B. Tedlock 1982;
Girard 1948). It is worth mentioning here that the
verb associated with the 'altar/pedestal' of the Three
Hearthstones and the events that took place on the
era base is spelled JEL-ja, which Barbara MacLeod
first read as jelaj, meaning 'was changed' (Callaway
2011:45-46, 283-286; Freidel and MacLeod 2000).
Similarly, the K'iche' name for solar zeniths contains
the cognate jal-bal 'place of change' (B. Tedlock
1982:180), suggesting that these texts may indeed refer to the intended solar zenith using nearly identical
terminology.
Given the specific ways in which K'ahk' Uti'
Witz' K'awiil appears to have measured the Metonic
cycle using the K'atun and the Tzolk'in together, it is
possible that such measurements were similarly employed by the originators of the Long Count and that
they attempted to place the era base at the point of
the August 13 zenith at 14.8° N latitude. We find additional support for this in noting that the latitude of
Copan produces a very unique result when a K'atun
count begins precisely on the August 13 solar zenith. A count of one K'atun that begins on this solar zenith will conclude precisely on the April 30/
May 1 solar zenith, 260 days later. As we have seen,
the Metonic cycle of 19 tropical years is precisely
260 days less than one K'atun. Therefore, an idealized K'atun count that begins on August 13 seems to
suggest this very measurement of the tropical year
using the two solar zenith passages.
The results of this investigation provide specific
evidence that the contemporary K'iche' asterism of
the Three Hearthstones is directly related to the triadic First Three Hearthstones mentioned in Maya
hieroglyphic texts from the Classic period. Specif-
ically, the text on Stela 12 and its relationship with
Stela 10 provide evidence that K'ahk' Uti' Witz'
K'awiil used the Copan baseline as both a sidereal
alignment to the rising azimuth of Na'ir al Saif at
the center of the Three Hearthstones and an alignment to the sunrise on the K'atun ending 9.11.0.0.0.
Since it takes more than 71 years to accumulate only
one day of difference between the tropical year and
the slightly longer sidereal year, we might assume
that Maya astronomers would not have initially distinguished between them. Early astronomers in both
Mesopotamia and Egypt used heliacal star risings
as a primary measurement of the length of the year
(North 2008:28-30, 51). Ancient Egyptians observed
the heliacal rise of Sirius as a herald of the annual
flooding of the Nile, while Babylonian astronomers
kept track of the sidereal year as the only measurement of their year (Neugebauer 1969:140). Is it possible that the Maya eventually distinguished between
the sidereal and tropical years? By recording the first
appearance of the Orion Nebula and Na'ir al Saif in
comparison with the tropical year over several generations, Maya astronomers could have observed the
slowly accumulating difference between the tropical
year and the sidereal year. Given the relatively stable
azimuth position of the rising of Na'ir al Saif over
several hundred years, the Copan baseline could
have remained useful for this purpose for the duration of the Copan dynasty in the Classic period.
The Three Hearthstones are mentioned almost exclusively in statements describing the events on the
era base, where they are said to have appeared "at the
edge of the sky" in association with the verb jelaj,
which suggests the solar zenith. The earliest text to
mention the Three Hearthstones in association with
the era base is on the undated greenstone mask from
the Early Classic (see Figure 7). However, K'ahk'
Uti' Witz' K'awiil was the first to codify this association in monumental texts, and his initial reference to the Three Hearthstones is curiously found on
Stela 12, describing his witnessing the Hearthstones
"at the edge of the sky" in historical time on the
K'atun ending on 9.11.0.0.0. However, if K'ahk' Uti'
Witz' K'awiil and his predecessors were measuring
the sidereal year through observations of the heliacal rise of the Orion Nebula and Na'ir al Saif, it is
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possible that the statements about the Three Hearthstones on the era base involved a precessional calculation of the accumulated difference between the
tropical year and the sidereal year since the time of
the era base in 3114 BC.
If the originators of the Long Count themselves
intended to place the era base on the August 13 solar
zenith, using a fairly accurate measurement of the
tropical year, might they also have had an equally
accurate estimation of the sidereal year? We are
left to wonder whether the specific, and rather remote, back-calculated year of 3114 BC might have
been chosen using some calculation of the sidereal
year. If not, is it possible that there was an awareness of the sidereal year and precessional drift by
the time K'ahk' Uti' Witz' K'awiil dedicated his
monuments? Indeed, Alonso Mendez and Carol
"
Karasik (2014:99-101) have proposed that the Maya
of Palenque were aware that one of the belt stars of
Orion crossed the nadir at the time of the era base
zenith in 3114 BC. Thus, inscribed in the cosmological texts from the Tablet of the Cross (see Figure 5b), we find an even more detailed, local account
of creation involving the Three Hearthstones and
the completion of 13 Bak'tuns. Clearly, this is another version of the story that we first see mentioned
in the monuments of Copan. Was K'ahk' Uti' Witz'
K'awiil somehow back-calculating the changing celestial declination of the Three Hearthstones? This
would require a sophisticated knowledge of both the
tropical year and the sidereal year. Curiously, using
astronomical software to determine the sidereal position of where the Sun would have been on the era
base, we can see that the Sun was within six days of
the sidereal position where it appears on the K'atun
ending on 9.11.0.0.0. Depending on the value of his
estimation of the length of the sidereal year compared to the tropical year, perhaps K'ahk' Uti' Witz'
K'awiil was aware of this close equivalence. Indeed,
the evidence from Stela E and Stela 10 suggests that
the Copan baseline itself was being used to calculate
the sidereal year over shorter intervals of time.
Regardless of the calendar correlation used, the
sidereal equivalence of the Sun's position between
9.11.0.0.0 and the era base is interesting, if not exact.
It is important to note that if both of the GMT cor• 78
ARCHAEOASTRONOMY
relations are inaccurate and Na'ir al Saif was instead
literally first visible rising on 9.11.0.0.0, then it also
would have been very close to being first visible rising on the era base. However, as we have seen, if we
use the 584285 GMT correlation, the Sun rose at the
azimuth of the Copan baseline on 9.11.0.0.0, but the
Orion Nebula next to Na'ir al Saif would have been
first visible at this azimuth exactly one K'atun later,
on 9.12.0.0.0. Likewise, if the era base was intentionally chosen to begin a count on the August 13 solar
zenith in 3114 BC, one K'atun forward would arrive
exactly on the other April 30/May 1 solar zenith,
close to the day when the Orion Nebula would have
become first visible in that year. This harmonious
commensuration of the first appearance of the Orion
Nebula and the April 30/May 1 zenith at what would
have been the conclusion of the measurement of the
first K'atun of the era may have made for an idealized triangulation for the era base, when these three
measurements would have coincided. While there
is no evidence to suggest that the originators of the
Long Count necessarily incorporated the rising of
the Orion Nebula into their choice of era base, such
an organized measurement involving the two solar
zeniths and a sidereal marker may have had a similar precedent in the origination of the Long Count.
Elsewhere (Grofe 2007:92, 2009, 2011b:217), I
have proposed that the Pleiades may have been involved with the original formulation of the era base.
Assuming that the era base was intentionally chosen to be placed on the August 13 solar zenith at
14.8° N, the question remains why the era base was
placed in the specific, remote year 3114 BC, thousands of years prior to the initial use of the Long
Count in the first century BC. One proposal that
may help to explain this choice is that the originators
of the Long Count had developed some understanding of the difference between the length of the tropical year and the slightly longer sidereal year. Indeed,
the Pleiades precisely crossed the zenith at 14.8° N
latitude between the first and second centuries BC,
during the time immediately preceding the earliest attested Long Count date from Chiapa de Corzo,
given as 7.16.3.2.13, December 8, 36 BC (December 10, Julian) (Coe 1994:76). In addition, the Pleiades would have been first visible, heliacally rising
at dawn after close conjunction with the Sun at this
time on the very day of the April 30/May 1 solar
zenith passage, thereby announcing the day of the
solar zenith. Given that these two events were simultaneously paired during the very window of time,
and conceivably the place, in which the Long Count
was inaugurated, it is possible that the slowly accumulating difference between the recorded day of the
April 30/May 1 solar zenith and the increasingly
later heliacal rise of the Pleiades on the horizon allowed for the originators of the Long Count to backcalculate the era base to a time when the Pleiades
would have risen at a very different time of year. In
fact, in 3114 BC, the Pleiades would have risen heliacally due east, announcing the precise day of the
vernal equinox.
During the first two centuries BC, if a K'atun
count began on the August 13 solar zenith, the first
K'atun would conclude on the April 30/May 1 solar zenith, on the same day that the Pleiades first appeared rising at dawn. This type of pairing may have
been used at the end of the K'atun, and the changing results recorded over time would provide astute
observers with a measurement of both the tropical
year and the sidereal year, thereby yielding an observation of accumulated precession. Given the usefulness of the K'atun and the Tzolk'in for measuring
the Metonic year, the 260-day interval between the
two solar zeniths at the latitude of 14.8° N may have
served as a useful measuring tool when combined
with sidereal observations of the rise of the Pleiades.
Indeed, observations of the first and last appearance
of the Pleiades continue to be an important component of the agricultural year for contemporary Maya
people (Milbrath 1999:258).
If the Pleiades were an important sidereal marker
in the formative years of the Long Count, announcing the arrival of the April 30/May 1 solar zenith
and the beginning of the rains and the planting season for many Maya people, later authors of mythological narratives may have similarly attempted to
determine what analogous celestial marker would
have been first visible during the April 30/May 1 solar zenith at the time of the era base in 3114 BC. Little evidence exists to suggest that the originators of
the Long Count considered the Three Hearthstones
important. Instead, the specific involvement of the
Three Hearthstones within era base texts-as well
as the shared concept of a previous era ending after completing 13 Bak'tuns-may have been cosmological concepts that evolved later in Classic period
Copan, based on earlier principles of astronomical
measurement using the K'atun, the Tzolk'in, the two
solar zeniths, and sidereal observations of stars like
Na'ir al Saif. Such solar, lunar, and sidereal observations as we find in the monuments of K'ahk' Uti'
Witz' K'awiil suggest that Maya astronomers were
capable of making precise astronomical measurements over time involving calculations of the tropical
year, the sidereal year, and the eclipse year. Where
possible, further research on the inscriptions of these
various monuments will undoubtedly help to clarify
their context and meaning and their intended historical, mythological, and astronomical references.
Acknowledgments
I would like to thank Barb MacLeod for her ongoing support and feedback and her willingness to
collaborate and entertain new ideas and to generously share her years of experience. Special thanks
to Ed Barnhart and the Maya Exploration Center for providing the funding for my research and
travel to Copan, without which this article would
not have been possible. Thanks to John Carlson,
Shannon Kring Buset, Flavia Cueva, Bob Benfer,
Stanislaw Iwaniszewski, Carl Callaway, Hal Greene,
and Gerardo Aldana for their support, invitations,
and collaboration during the research and development of this article. I am likewise grateful to Martha
Macri and Matthew Looper for their sustained support and feedback. Thanks to the Carnegie Foundation for the generous usage of Sylvanus Morley's
original drawings. Finally, I would like to thank my
Copan field students and colleagues who helped with
measurements and photographs, and from whom I
derive much of my inspiration: Isabel Araujo, Satish
Bhatnagar, Denise Brown, Gopal Elluru, Krystan
Felt, Karlee Finch, Desislava Pavlova, Jonathan
Rushing, Jim Sievers, Liz Sivell, Mirabel Wigon,
Amanda Wright, Gary Young, and the Ch'orti' children of La Pintada. Any errors contained within this
article are solely those of the author.
VOLUME XXV 2012-2013
79
e = atan2[sin(-0.001051229). cos(0.259058243),
Notes
l. The Long Count is a vigesimal positional system of
repeating cycles of 360 days that reckons from an era base
several thousand years prior to the first evidence of the
use of the system in the first century BC. The two widely
accepted Goodman-Martinez-Thompson (GMT) correlations are given by the varying Julian Day Numbers associated with the era base. The 584283 GMT correlation
constant places the era base on August 11 , 3114 BC (September 6, Julian), whereas the 584285 GMT correlation
constant places the era base on August 13, 3114 BC (September 8, Julian). Long Count notation is transcribed with
the largest period first , typically beginning with the Bak'tun
(400 X 360 days), followed by the K'atun (20 X 360 days),
the 360-day Tun, the Winal (20 days), and the K'in (I day).
Therefore, the Long Count date 9.11.0.0.0 commemorates
K'atun 11 of Bak'tun 9 after the era base, and it fell on the
day 12 Ajaw 8 Keh, with 12 Ajaw being the name of the
day in the Tzolk'in, a concurrent 260-day cycle composed
of 20 named days and a cycle of 13 numerals. The date
8 Keh follows as the Haab position, a canonical solar cycle
of 365 days composed of 18 periods of 20 numbered days
with an additional 5-day period.
2. The formula for the calculation of an initial forward
azimuth bearing between two coordinates, point A and
point B, can be stated in radians as:
e=
· cos(cp 2) , cos(cp 1) • sin(cp2) sin( cp 1) • cos( cp 2) •
e = degrees mod 360°
= difference in longitude between points A and B
cp 1 = latitude of point A
cp 2 = latitude of point B
Coordinates for point A, Stela 12 = 14°50'34.6" N
= 14.833783°
= 0.258898354 rad
89°11'3.53" w
= 89.124083°
= 1.5555087 rad
Coordinates for point B, Stela 10 = 14°50'1.62" N
= 14.842944°
= 0.259058243 rad
89°7'26.7" w
= 89.184314°
= 1.5565599 rad
• 80
ARCHAEOASTRONOMY
cos"(0.258898354) · sin(0.259058243)
- sin(0.258898354) · cos(0.259058243)
· cos(-0.001051229)]
= atan2(-0.001016151 , 0.247632843
- 0.247472817)
= atan2(-0.00101615l , 0.000160026)
= - 1.414597 radians= -81.0504° = 278.9496°
278°56'58.56" from Stela 12 to Stela 10
=
The Haversine formula (Sinnott 1984) can be used with the
above to determine distances using a spherical model of the
Earth, where R = mean radius of the earth = 6,371 km :
c = 2 · atan2(Va, V(l - a))
d= R·c
This provides a distance of 6,551 m between Stela 12
and Stela 10.
Recognizing the ellipsoidal oblateness of the actual shape
of the Earth, the Vincenty formu la (Vincenty 1975) can be
used to determine a much more accurate bearing, as well
as a more accurate distance between two coordinates. Using a JavaScript calculator for the Vincenty formu la (Veness
2014) provides a slightly different bearing from Stela 12 to
Stela 10 of 278°48'20.47", and a distance of 6,558.97 m between them.
3. I obtained these estimates using Starry Night Pro
Plus 6.2.3 (Simulation Curriculum Corp. 2009), which has
programmed within it current 12000 measurements for the
variability in the obliquity of the ecliptic, the elliptical orbit of the Earth, and the Earth's precessional rotation, which
together affect the velocity of the Earth and the azimuth
position of the Sun on a given date over the past several
thousand years.
4. The formula for calculating the declination and right
ascension of any star through time is stated in David H.
Kelley and colleagues (2011:67):
sin( a - z)cos 8 = sin( a 0 + i;;)cos 80
cos( a - z)cos 8 = cos( a 0 + I;;) cos
e cos 80 -
sin
e sin 80
sin 8 = cos( a 0 + i;;)sin e cos 80 + cos e sin 80
z = [(0.0000051 · T + 0.0003041) · T
+ 0.6406161] · T
e=
[( -0.0000116 · T -0.0001185) · T
+ 0.5567530] · T
= [(0.0000050 · T + 0.0000839) · T
+ 0.6406161] · T
T = number of centuries, measured negatively
before 12000
sin o = cos( a 0 +
e cos o0 + cos e sin o0
sin 8 = cos(83.85833334° - 8.627293925)
· sin(-7.493647658) · cos(-5.91 °)
+ cos(-7.493647658) · sin(-5.9JO)
sino= cos(75.23103942) · sin(-7.493647656)
· cos( -5.91 °) + cos( -7.493647658)
· sin(-5.91 °)
sino= (0.254921954)(-0.130416271 )(0.994684861 )
+ (0.991459327) . (-0.102966144)
t = calendar date of interest
JDN = Julian Day Number
T = (t- 2000.0)/100 = (JDN - 2451545.0)/36525
a 0 = right ascension of star in 12000
00 = declination of star in 12000
a = right ascension of star in target date
8 = declination of star in target date
To determine the declination of Na'ir al Saif on 9.11.0.0.0:
9 .11.0.0.0 = October 14, AD 652 = JDN 1959485:
T = -492060/36525 = -13.47186858
z = {[0.0000051 ( - 13.47186858)
+ 0.0003041] ( -13.47186858)
+ 0.6406161} . ( -13.47186858)
z = -8.587574056
e=
{[ -o.oooo116 c-13.47186858)
-0.0001185] ( - 13.47186858)
+ 0.5567530} . ( -13.47186858)
e=
-7.493647656
= {[0.0000050 (-13.47186858)
+ 0.0000839] ( -13.47186858)
+ 0.6406161} . ( -13.47186858)
= -8.627293925
For Na'ir al Saif (Kelley et al. 2011:56):
a 0 = 5h35'26" = 5.590555556h = 83.85833334°
sino= -0.033069264- 0.102086743
sino= -0.135156007
0 = -7.767641109° = -7°46'3.5"
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