Can Astronomical Alignments Be Found in the Orientation of Ancient Maya Structures in Northwestern Belize?
The archaeological ruins of Northwestern Belize have been studied extensively by the Maya Research Program (MRP), the Programme for Belize, and the National Institute of Culture and History for nearly three decades, and a great deal has been learned about Maya trade economies, the nature of spatial and structural organization, and the stratification of social hierarchies from this endeavour.[1] Conversely, a comparatively smaller amount of research has been undertaken from the perspective of Skyscape Archaeology. The goal of this research is to investigate the orientations of public architecture at two MRP excavation sites: Blue Creek, a large site with published reference to both a Pseudo-E-Group and Quincunx Group, and Xnoha, a medium sized site which has never been examined from an archaeoastronomical perspective. After a brief synopsis of the literature pertaining to the astronomical and cosmological content in the local archaeological record, the fieldwork methodology and data analysis of each site, followed by an interpretation of the results of this research will be discussed in order to ascertain whether astronomical alignments can be found in the orientation of ancient Maya structures in Northwestern Belize.
Skywatchers of Ancient Belize
The orientation of select Maya structures to the rising of celestial bodies has been demonstrated, discussed, and debated for nearly a century, since Frans Blom of the Carnegie Institute first identified that the alignment of the structures of Uaxactun’s E-Group ‘corresponded very closely to the amplitudes of the sun at the solstices and the equinoxes.’[2] Subsequently, the term ‘E-Group’ has been adopted from this type-site to represent a particular architectural assemblage consisting of a radial western pyramid opposite three north-south aligned structures which define the plaza’s eastern edge, and which may have astronomical meaning and function.[3] These three temples theoretically represent alignment points for the winter solstice (southern-most temple), equinox (center temple), and summer solstice (northern-most temple) when viewed from a position upon the western temple. In 2005, Thomas Guderjan, Director of the Maya Research Program, defined the term ‘Pseudo-E-Group’ as a sacred architectural complex which was ‘non-functional for either solar or agriculturally oriented observation’ based upon its relationship to the contour of the horizon.[4] This architectural assemblage differs from its namesake in that it is comprised of only two temples on its eastern edge, possibly supported by a common substructure or platform, with no western temple.[5] The supposition is that any celestial event would be viewed, instead, from some smaller structure centered within the plaza itself, for instance a platform (stone or wooden), stele, altar, or even a pole or stick.
A variety interpretations exist as to the purpose and function of E-Groups, summarized by the following six theories: they function as solar observatories for measuring the solstices and/or solar zenith passage (based upon the observations from Uaxactun); they function as specialized observatories for marking the positions of the sun and Venus; they are seasonal orientation calendar-buildings applied to large-scale trade movements; they can be regarded as theatres or proscenia that served as planetariums rather than observatories; they are strictly commemorative astronomical complexes, or lastly, they are non-functioning symbolic architectural complexes.[6] The debate over function exists due to the fact that many E-Groups do not align to the declinations associated with solstice risings, and have subsequently been dismissed as non-functional with respect to the term observatory. By way of example, at the site of Xunantunich, Belize, field observations of the 1991 June solstice sunrise by James Aimers and colleagues ‘estimated the sun to have first appeared shortly after 6 AM…close to the southern edge of the north eastern structure’ leading the team to conclude that the ‘observations do not support the persistent belief that E-groups were astronomically markers of the solstices and equinoxes.’[7] Yet other sites, such as Baking Pot, do produce convincing alignments, so the debate goes on.[8] The question posed by this research is whether or not similar evidence of astronomical alignments can be found in the Orange Walk District of Northwestern Belize between the Rio Bravo and the Mexican border.
Figure 1: Model of Xunantunich E-Group with the expected solstice/equinox sight-lines drawn in yellow and the approximate 1991 June Solstice sunrise sight-line as reported by Aimers in orange. Photo by author, 2015
Figure 2: Map depicting select Maya ruins of Northwestern Belize
including the sites of Blue Creek and Xnoha
The scant scholarly literature pertaining to Northwestern Belize which addresses astronomical and cosmological implications in the archaeological record is limited to the sites of Blue Creek, La Milpa, and to a much lesser extent, Quam Hill. An early report found that these three sites (along with Punta de Cacao further south) were ‘the only sites of Northwestern Belize currently known to contain ball courts,’ which were sacred architectural manifestations of the Popol Vuh creation story.[9] Blue Creek and Quam Hill (along with Chan Chich and San Jose further to the south) have also been identified as sites with possible Pseudo-E-Groups, and a primary focus of this study was to be the investigation of the Pseudo-E-Group comprised of Structures 13 and 14 on the eastern edge of Plaza B at Quam Hill, which has not been explored since originally mapped by Michael Lindeman in 1990.[10] Unfortunately, a recent change in land ownership has made access to this obscure and unexcavated site problematic.[11] At the nearby site of La Milpa, Brett Houk and Gregory Zaro, contributing to the conversation on the influence of cosmology on Maya city-plans, argued that dedicatory caches may be understood as unique deposits ‘while at the same time signalling a much larger, ritually engineered landscape that incorporates other caches and architectural features.’[12] These caches often take the form of two lip-to-lip ceramic vessels containing items such as sea sponges and stingray spines topped by jade and stones, representing the Maya three-part cosmos of ‘the primordial sea, the earth based materials connected to the Witz Mountain, and the dome-shaped roof of the sky.’[13] They suggest that the placement in Plaza B of several dedicatory caches along with an altar from the same construction phase ‘may have served to link the unseen ritual deposits to the functional plaza’ and thus create an engineered sacred space based upon Maya cosmology, if not astronomy.[14]
In 2005 Zaro, along with Jon Lohse, reported the discovery an architectural assemblage within a residential satellite of Blue Creek which they dubbed the Quincunx Group, claiming it reflected the Maya concept of a quadripartite cosmology, was oriented to the June solstice, and provided ‘evidence that some rural communities may also have had access to and control over esoteric knowledge involved in agricultural practice’.[15] The assemblage was comprised of five structures- ‘a central masonry room block and four low, broad, circular cobble platforms positioned in inter-cardinal directions’ forming the shape of a cosmologically significant quincunx.[16] Despite questionable architectural assumptions, the lack of documented azimuth, horizon altitude, and declination measurements, or any known analogous non-civic assemblages, their assertions had gone unchallenged over the last decade. Another primary focus of this study was to be the ‘ground-truthing’ of these claims and the measurement of the Quincunx Group’s reported orientation to the summer solstice. Unfortunately, initial attempts to locate the structures (accompanied by participants of its original excavation) were unsuccessful, and it was eventually discovered that the site had been completely destroyed by modern agricultural land use. The significance of the claim that rural Maya built astronomically aligned and cosmologically significant architecture independent of elite or civic influence was that if true, this site would have been the sole example cited in the Maya region, and validation of these claims is now impossible without the discovery of a similar archaeological assemblage.
The Pseudo-E-Group of Blue Creek
The initial objective of this fieldwork was to investigate the proposed solstitial alignment of the Quincunx Group at Blue Creek, the unexcavated Pseudo-E-Group at Quam Hill, and the orientations of various public architecture at Xnoha to ascertain the likelihood of astronomical alignment. Due to the destruction of the first site and the inaccessibility of the second, the project shifted focus to include instead the archetypal Pseudo-E-Group of Blue Creek. Blue Creek, which sat atop the Rio Bravo Escarpment, rising abruptly nearly 150 meters from the adjacent coastal plain lowlands, was a wealthy independent kingdom complete with royal tombs and columned architecture.[17] The Pseudo-E-Group, comprised of Structures 2 and 3 on the eastern edge of Plaza A, has been completely reclaimed by forest growth. Excavations of the group began in 1998, and although Structure 3 had been extensively looted, an anthropomorphic effigy vessel was recovered from a dedicatory cache buried at the base of its central staircase.[18] W. David Driver and Phil Wanyerka identify the deity depicted on this vessel as the sun god Kinich Ahau, and suggest that its burial at this location may represent ‘the sun’s descent into the underworld on the winter solstice.’[19]
Figure 3: Structures 2 (left) and 3 (right) covered by forest re- growth at Blue Creek, Belize.
Photo by author, 2015
Guderjan notes that ‘if this pair of buildings had functioned as an observatory, the third building—the viewing point of the complex—would be in the mid-plaza area.’[20] In 1999 MRP conducted surface inspections and excavations in the center of the plaza ‘but no evidence of any sort of marker for a viewing point was located.’[21] However, it should be considered that if such a viewing point had been a platform of wooden construction, it is reasonable to expect that evidence of its construction would remain elusive in the archaeological record. The choice of the western viewing position to use for this fieldwork, in the absence of a radial pyramid or evidence of backfill from the 1999 test excavations, was a purely phenomenological one. The location, or reference point, was chosen not only for its position at an approximate 90° alignment with Magnetic North and the northern edge of structure 3, but also due to its relation to the position of structures 1, 4, and 5 surrounding it. The Latitude and Longitude of the reference position was recorded as 17° 51.632’N 88° 53.860’W using the Garmin eTrex20 with a 100% sample confidence reading over a 5 minute and 30 second averaging time. A surveyor’s Prism Pole was placed at the reference point and used as the back-sight for all subsequent measurements, which were taken using the Suunto Tandem-360PC/360R Compass/Clinometer. Due to the fact the temples were no longer unearthed, and the choice of the western viewing point was arguably arbitrary, the precision afforded by use of a theodolite was deemed unnecessary. Several radial GPS readings were taken in order to calculate the magnetic declination, but due to uncertainty introduced by readings with lower averaging times at the radial points, the decision was made to use the value of + 0.7° East generated by the World Magnetic Model (WMM) from the National Oceanographic and Atmospheric Association (NOAA).
Compass readings were taken recording the azimuth angle from magnetic north to various strategic points atop both Structures 2 and 3 as illustrated in Figure 4. A second surveyor’s pole was placed approximately midway up each temple where the central staircase would have been, and compass measurements were taken from this vantage point back towards the reference point; these readings were then averaged with the top-center readings of each temple respectively. Additionally, clinometer readings were taken to measure the horizon altitude from the reference point to the artificial horizon, or skyscape, created by the temple structures.
It is theorized that this assemblage could not have been used as an accurate observatory based on the elevation of Plaza A, which is ‘approximately 110 m above the base of the escarpment’ and, as Guderjan explains, ‘the sun would not be observed rising above Structures 2 and 3 until midmorning, when it would be too high and too large in the sky to measure the sunrise location with any precision.’[22] His supposition is that if this were indeed an observatory, Structure 2 would have marked the June solstice and Structure 3 the winter solstice.
Figure 4: Map of Blue Creek Site Core –Plaza A, including the Pseudo-E-Group- showing azimuth angles from True North, modified from Guderjan 2005
Using the latitude of the reference point (17.86051667°N), the measured horizon altitude of +10° defined by the skyscape created by the temples, and the azimuth angles corrected for magnetic declination as shown in figure 6, the declination values of the sunrise were computed to be 27.94°, 20.81°, 16.55°, 2.39, -1.35°, and -6.01° respectively. These values were compared to a ‘Table of the Declination of the Sun’ to obtain sunrise dates at these particular declinations.[23] Two declinations in particular, 66.55° (16°33’) and -1.34° (-1°20’) equate to interesting sunrise dates. As viewed from the reference point selected for this fieldwork, the sun will rise over the top-right edge of Structure 2 (Azimuth 75.7°, Declination 16.55°) on both May 7th and August 7th. Sun Position Calculator applications show that May 7th and August 7th are the dates of solar zenith passage for the coordinates 17°51.6’N 88° 53.8’W.[24] Anthony Aveni points out that ‘the passage of the sun across the zenith in the tropics...is central to the operation of a developed indigenous calendar despite having no significance or importance in the West.’[25] From the same vantage point, the sun will rise over the top-left edge of Structure 3 (Azimuth 94.7°, Declination -1.34°) on both March 18th and September 27th. This corresponds to the dates of Vernal and Autumn Equinox during the Maya Classic Period.[26] Minor shifts in the position of the reference point could, of course, ‘fine tune’ these alignments.
Shared Orientations in Xnoha
The nearby site of Xnoha is a medium-sized center originally located and named by Guderjan in the early nineties; and though some test excavation and mapping was done from 2001-2002, serious excavation at the site has only taken place over the last four years by the Maya Research Program.[27] It is evident from even a cursory glance at the site map of Xnoha that the public architecture seems to share a counter-clockwise skew from the cardinal directions. In reference to a survey of over seventy Maya sites in the southern Campeche region of Mexico, just to the northwest of Xnoha, Ivan Šprajc reports that,
The orientation at all the sites tend to be skewed clockwise from cardinal directions. This regularity, which is- in spite of exceptions found in certain areas and periods- a well-known pan-Mesoamerican characteristic, is a first indicator suggesting an astronomical basis of these orientations.[28]
The goal of this research at Xnoha was to verify a shared orientation of the public architecture, calculate the declination of the sun at this azimuth, and evaluate possible interpretations of the findings.
Figure 5: Map of Xnoha Site core, modified from Lohse/Wolfe 2002. Public architecture measured include Structures 1, 2, 3, 4, 10, 22 and 77.
The azimuth angles from magnetic north were recorded for much of the public architecture at Xnoha, but this research will focus on Structure 77 (The Shrine) and Structure 10 (the Temple) -both of which were currently being excavated during the MRP 2015 season and therefore provided more precise measurements due to exposed architecture- and their relation to pre-recorded measurements of Structures 1 and 3. Attempts to follow the procedures laid out by Clive Ruggles using a Digital Theodolite to measure the declination of the sun were used to verify compass/clinometer measurements at the Shrine, but were thwarted by both overcast skies and the rainforest canopy everywhere else.[29]
Figure 6: Author at Xnoha taking measurements with Topcon DT-20 Digital Theodolite. Photo by Pete Maganya, 2015
Figure 7: Structure 77, the Shrine, viewed from the south western corner staircase.
Photo by Greg Savoie 2005. Used with permission.
The methodology used at Xnoha, therefore, was very similar to that used at Blue Creek; two surveyor’s poles were placed adjacent to the best example of exposed wall for each particular structure and the azimuth compass reading from magnetic north were taken in both directions and averaged together. Again, radial GPS readings were taken in order to calculate the Magnetic Declination at Plaza A in Xnoha, but the choice was made to use the value of + 0.12° east obtained from NOAA, and though taken into account in all calculations, rounded down in the subsequent discussions.
At the Shrine, the northern wall was measured to be 101° from magnetic north. The theodolite was used to verify this reading against the MRP site datum point. These readings were made with the greatest amount of accuracy and precision due to the amount of exposed architecture.
The azimuth angle of Structure 10 was measured at 102°, but this reading may be in doubt for several reasons including the state of the excavation at the time of measurement. It is suggested that a re-measurement at a time further along into the excavation would have produced an azimuth reading closer to 101°. Measurements of Structures 1 and 3, although little exposed architecture remained uncovered, produced results of 101° within a margin of error. This is supported by Sam McLellan’s 2013 excavation report which states that ‘Structure 1 is the southernmost structure of the courtyard and is an ancestral shine associated with Structure 3’, and further notes that ‘the structure is orientated 11 degrees east of magnetic north, and as such, orientated [at 101°] with Structure 3 as well.’[30] The orientations of structures 2, 4, and 22 were also measured, but to a lesser degree of precision; little exposed architecture was available for reference as these structures have yet to be excavated. With the horizon completely obscured by the rainforest, a horizon profile was generated using tools from the website HeyWhatsThat.[31] A horizon altitude of +0.44 was determined from the intersection of the horizon line at 101°. Though the horizon (which may have been visible during the Classic Period due to deforestation for the production of plaster) shows no significant feature at 101°, the solar declinations may still point to significant sunrise dates.
Figure 8: Horizon profile from 17° 56.65’ N 89° 0.12’ W, modified from www.heywhatsthat.com with vertical scale exaggerated 10x and the horizon altitudes of 0° and 1° depicted. Vertical line intersects the horizon at an azimuth of 101° and a horizon altitude of +0.44°.
Discussion
It is intuitive to assume that the two eastern temples of a Pseudo-E-Group would align to the summer and winter solstices, and if they do not accurately align, the logical deduction would be that they are non-functional as an observatory and serve a more ritualistic and symbolic purpose. This research has shown that, at the site of Blue Creek at least, the eastern temples of the Pseudo-E-Group may have aligned instead to the Solar Zenith Passage and the Equinoxes, depending upon the actual position of the skywatcher. Aveni points out that observance of the zenith passage served a practical purpose in that ‘the first one announces the rains at the end of April, telling that it is time to clear the fields for planting, and the second… also signals rain accompanied by wind.’[32] Furthermore, use of the term observatory implies a level of precision which may be problematic, while Grant Ayleworth finds it sufficient to suggest:
If E-Groups can be interpreted more loosely in terms of astronomy, rather than meeting strict solar alignment requirements, in astronomical terms, it seems that they may have delimited the zodiacal band area of the sky, this area having been of great interest to the ancient Maya since it was within this band that the sun, moon, planets, zodiacal constellations, and the zodiacal light appeared. Thus, while E-Groups may generally exhibit azimuths that point toward the solstices or mark the approach of first zenith passage, they more importantly, and in a broader sense, delimit the path of the zodiac and thereby were the locus of multi-layered hierophanies.[33]
In view of this interpretation, one can imagine the Skywatchers of Blue Creek gathered in Plaza A to watch in silence as the Milky Way would rise in the east, as if emerging from the space between the temples of the Pseudo-E-Group.
Table 1: Histogram showing azimuth orientations of public architecture at Xnoha
At the site of Xnoha, the question remains as to what astronomical event could have aligned to the shared azimuth of 101°. Aveni and Hartung suggest that ‘if we find alignments that are confined to a narrow azimuthal range in a sample of buildings spread far apart in space…there can be no conceivable way of actually laying out the chosen direction other than by the use of astronomical bodies at the horizon as reference objects.’[34] The 101° orientation from a latitude of 17.944°N, along with the horizon altitude of +0.44°, yields a solar declination of -10.98°. This would align to the sunrise on the days of February 21st and October 22nd. Interestingly, Ivan Šprajc has found that ‘analyses of large data samples from central Mexico and the Maya area have revealed that the intervals separating sunrise and sunset dates recorded by orientations at a particular site tend to be multiples of 13 or 20 days, which were basic periods of the Mesoamerican calendrical system.’[35] The total number of days between October 22nd and February 19th happens to be 120 days, or 6 x 20 days, or one third of the haab cycle of 360 days.
It is also interesting to note that sites with Pseudo-E-Groups seem to cluster around the Rio Bravo Escarpment, and these sites do not exhibit a shared orientation of public architecture, as is seen at Xnoha. Xnoha’s shared orientation seems to have more in common with its Mexican neighbours to the northwest. Indeed, Colleen Hanratty of the Maya Research Program suggests that there are important differences in the composition of ceramics between these sites.[36] More research would be needed though, to verify any cultural distinctions as evidenced by differences in the application of astronomical alignments.
In conclusion, the goal of this research was to investigate the public architecture at two Maya sites, Blue Creek and Xnoha, to determine whether astronomical alignments can be found in the orientation of ancient Maya structures in Northwestern Belize. Measurements of the azimuth angles of Structures 2 and 3, which form the Pseudo-E-Group of Blue Creek, in relation to a viewing position phenomenologically chosen, yield solar declinations which align to the sunrise dates of the Solar Zenith Passage and the Equinox during the Classic Period, and it has been shown that the solar zenith was a culturally significant event for the Maya. Furthermore, measurements of the public architecture at the site of Xnoha demonstrates a shared orientation of 101°, the solar declinations of which point to sunrise dates of October 22nd and February 19th. These dates are separated by a multiple of 20 days (6 x 20 = 120) and may be, according to Šprajc, calendrically significant. Though this small corner of the Maya world may not boast the same extravagant examples of astronomical alignment as can be found at The Temple of the Seven Dolls at Dzibilchaltun or El Caracol at Chichen Itza in the Yucatán, it has been argued here that architectural orientations to celestial risings were indeed an important part of city planning in Northwestern Belize.
Acknowledgements: Special thanks to Tom Guderjan and Colleen Hanratty of the Maya Research Program, without whom this research would not have been possible. Additional thanks to MRP staff and associates Greg Savoie, Alex Pastrana, and Pete Maganya.
Bibliography
Aimers, James J., and Prudence M. Rice, ‘Astronomy, Ritual, and the Interpretation of Maya “E-Group” Architectural Assemblages’, Ancient Mesoamerica, Vol. 17:1 (2006), pp. 79-96
Aveni, Anthony F., Skywatchers: A Revised and Updated Version of Skywatchers of Ancient Mexico, revised edition (Austin, TX: University of Texas Press, 2001)
Aveni, A. F. and H. Hartung, ‘Maya City Planning and the Calendar’, Transactions of the American Philosophical Society, Vol. 76, No. 7 (1986), pp. 1-87
Aylesworth, Grant R., ‘E-Group Arrangements’, in The Handbook of Archaeoastronomy and Ethnoastronomy, ed. by Clive Ruggles (New York: Springer Reference, 2015)
Guderjan, Thomas H., Michael Lindeman, Ellen Ruble, Froyla Salam, and Jason Yeager, ‘Archaeological Sites in the Rio Bravo Area’, in Maya Settlement in Northwestern Belize: The 1988 and 1990 Seasons of the Rio Bravo Archaeological Project, ed. Thomas H. Guderjan, (Lancaster: Labyrinthos, 1991)
Guderjan, Thomas H., ‘E-Groups, Pseudo-E-Groups, and the Development of the Classic Maya Identity in the Eastern Peten’, Ancient Mesoamerica, Vol. 17 (2005), pp. 1–9
Guderjan, Thomas H., The Nature of an Ancient Maya City: Resources, Interaction, and Power at Blue Creek, Belize, (Tuscaloosa: University Alabama Press, 2007)
Guderjan, Thomas, and Tim Preston, ‘Preliminary Report of 2012 Excavations at the site of Xnoha’ in The 21st Annual Report of the Blue Creek Archaeological Project, ed. by Thomas H. Guderjan and C. Colleen Hanratty Submitted to the Institute of Archaeology, National Institute of Culture and History, Belmopan, Belize, (Tyler: Maya Research Program, 2013)
Guderjan, Thomas H, personal communications, May-June 2015
Hanratty, Colleen, personal communications, June 2015
HeyWhatsThat, <http://www.heywhatsthat.com/> accessed July 24th 2015
Houk, Brett A., and Gregory Zaro, ‘Evidence for Ritual Engineering in the Engineering in the Late/Terminal Classic Site Plan of La Milpa, Belize’, Latin American Antiquity, Vol. 22, No. 2 (June 2011), pp. 178-198
McLellan, Sam, ‘Excavations at Structure 1, Xnoha’ in The 22st Annual Report of the Blue Creek Archaeological Project, ed. by Thomas H. Guderjan and C. Colleen Hanratty Submitted to the Institute of Archaeology, National Institute of Culture and History, Belmopan, Belize, (Tyler: Maya Research Program, 2014)
Photovoltaic Education Network, Sun Position Calculator, <http://www.pveducation.org/pvcdrom/properties-of-sunlight/sun-position-calculator>, accessed July 26th, 2015
Ricketson, Oliver G., ‘Excavations at Uaxactun’, Scientific Monthly, Vol. 37(1), July 1933, pp. 72-86
Ruggles, Clive, Astronomy in Prehistoric Britain and Ireland, (New Haven and London: Yale University Press, 1999)
Sanford, Walter, ‘Table of the Declination of the Sun, Mean Value for the Four Years of a Leap-Year Cycle, < http://www.wsanford.com/~wsanford/exo/sundials/DEC_Sun.html> accessed July 26th, 2015
Savoie, Gregory P., ‘Maya E-Group Assemblages’, Lecture given to the Maya Research Program, Blue Creek, Belize, June 25th, 2015
Šprajc, Ivan, 'Teotihuacan Architectural Alignments in the Central Maya Lowlands?’ in Archaeoastronomy and the Maya, ed. Gerardo Aldana Y Villalobos and Edwin L. Barnhart, (Oxford and Havertown: Oxbow Books, 2014)
Šprajc, Ivan, ‘Astronomical Correlates of Architecture and Landscape in Mesoamerica’ in The Handbook of Archaeoastronomy and Ethnoastronomy, ed. by Clive Ruggles (New York: Springer Reference, 2015)
Time and Date, < http://www.timeanddate.com/calendar/seasons.html?year=600>, accessed July 26th, 2015
Zaro, Gregory, and Jon C. Lohse, ‘Agricultural Rhythms and Rituals: Ancient Maya Solar Observation in Hinterland Blue Creek, Northwestern Belize’, Latin American Antiquity, Vol. 16, No. 1 (Mar., 2005), pp. 81-98
---------------------------------------------------------------------------------------------------------------------------------------------------
[1] Thomas H. Guderjan, The Nature of an Ancient Maya City: Resources, Interaction, and Power at Blue Creek, Belize, (Tuscaloosa: University Alabama Press, 2007) pp. 1-2
[2] Oliver G. Ricketson, ‘Excavations at Uaxactun’, Scientific Monthly, Vol. 37(1), July 1933, pp. 72-86
[3] James J. Aimers and Prudence M. Rice, ‘Astronomy, Ritual, and the Interpretation of Maya “E-Group” Architectural Assemblages’, Ancient Mesoamerica, Vol. 17:1 (2006), pp. 79
[4] Thomas H. Guderjan, ‘E-Groups, Pseudo-E-Groups, and the Development of the Classic Maya Identity in the Eastern Peten’, Ancient Mesoamerica, Vol. 17 (2005), p.1
[5] Gregory P. Savoie, ‘Maya E-Group Assemblages’, Lecture given to the Maya Research Program, Blue Creek, Belize, June 25th, 2015
[6] Grant R. Aylesworth, ‘E-Group Arrangements’, in The Handbook of Archaeoastronomy and Ethnoastronomy, ed. by Clive Ruggles (New York: Springer Reference, 2015) p. 784
[7] Aimers and Rice, ‘Interpretation of Maya E-Group Assemblages’, p.85
[8] Aimers and Rice, ‘Interpretation of Maya E-Group Assemblages’, p.85
[9] Thomas H. Guderjan, Michael Lindeman, Ellen Ruble, Froyla Salam, and Jason Yeager, ‘Archaeological Sites in the Rio Bravo Area’, in Maya Settlement in Northwestern Belize: The 1988 and 1990 Seasons of the Rio Bravo Archaeological Project, ed. Thomas H. Guderjan, (Lancaster: Labyrinthos, 1991) p. 81
[10] Guderjan, ‘E-Groups and Pseudo-E-Groups’, p. 5
[11] Thomas H. Guderjan, personal communications, May-June 2015
[12] Brett A. Houk, and Gregory Zaro, ‘Evidence for Ritual Engineering in the Engineering in the Late/Terminal Classic Site Plan of La Milpa, Belize’, Latin American Antiquity, Vol. 22, No. 2 (June 2011), p. 195
[13] Guderjan, The Nature of an Ancient Maya City, p.26
[14] Houk and Zaro, ‘Evidence for Ritual Engineering at La Milpa’ p.196
[15] Gregory Zaro and Jon C. Lohse, ‘Agricultural Rhythms and Rituals: Ancient Maya Solar Observation in Hinterland Blue Creek, Northwestern Belize’, Latin American Antiquity, Vol. 16, No. 1 (Mar., 2005), p. 81
[16] Zaro and Lohse, ‘Agricultural Rhythms and Rituals’ p.82
[17] Guderjan, The Nature of an Ancient Maya City, p.18
[18] Guderjan, The Nature of an Ancient Maya City, p.23
[19] Guderjan, The Nature of an Ancient Maya City, p.23
[20] Guderjan, ‘E-Groups and Pseudo-E-Groups’, pp. 2-5
[21] Guderjan, ‘E-Groups and Pseudo-E-Groups’, pp. 2-5
[22] Guderjan, ‘E-Groups and Pseudo-E-Groups’, p.5
[23] Sanford, Walter, ‘Table of the Declination of the Sun, Mean Value for the Four Years of a Leap-Year Cycle, < http://www.wsanford.com/~wsanford/exo/sundials/DEC_Sun.html> accessed July 26th, 2015
[24] Photovoltaic Education Network, Sun Position Calculator, <http://www.pveducation.org/pvcdrom/properties-of-sunlight/sun-position-calculator>, accessed July 26th, 2015
[25] Anthony F. Aveni, Skywatchers: A Revised and Updated Version of Skywatchers of Ancient Mexico, revised edition (Austin, TX: University of Texas Press, 2001) p.40
[26] Time and Date, < http://www.timeanddate.com/calendar/seasons.html?year=600>, accessed July 26th, 2015
[27] Guderjan, Thomas, and Tim Preston, ‘Preliminary Report of 2012 Excavations at the site of Xnoha’ in The 21st Annual Report of the Blue Creek Archaeological Project, ed. by Thomas H. Guderjan and C. Colleen Hanratty (Tyler: Maya Research Program, 2013) p.23
[28] Šprajc, Ivan, 'Teotihuacan Architectural Alignments in the Central Maya Lowlands?’ in Archaeoastronomy and the Maya, ed. Gerardo Aldana Y Villalobos and Edwin L. Barnhart, (Oxford and Havertown: Oxbow Books, 2014) pp. 41-43
[29] Ruggles, Clive, Astronomy in Prehistoric Britain and Ireland, (New Haven and London: Yale University Press, 1999) pp. 164-171
[30] Sam McLellan, ‘Excavations at Structure 1, Xnoha’ in The 22st Annual Report of the Blue Creek Archaeological Project, ed. by Thomas H. Guderjan and C. Colleen Hanratty Submitted to the Institute of Archaeology, National Institute of Culture and History, Belmopan, Belize, (Tyler: Maya Research Program, 2014) p.23
[31] HeyWhatsThat <http://www.heywhatsthat.com/> accessed July 24th 2015
[32] Aveni, Skywatchers, pp.40-41
[33] Aylesworth, ‘E-Group Arrangements’ p.789
[34] A. F. Aveni and H. Hartung, ‘Maya City Planning and the Calendar’, Transactions of the American Philosophical Society, Vol. 76, No. 7 (1986), p. 7-8
[35] Ivan Šprajc, ‘Astronomical Correlates of Architecture and Landscape in Mesoamerica’ in The Handbook of Archaeoastronomy and Ethnoastronomy, ed. by Clive Ruggles (New York: Springer Reference, 2015) p. 715
[36] Colleen Hanratty, personal communications, June 2015