Sundial, calendar and Khmer temples
Astro-archaeology = Astroarchaeology
Archaeo-astronomy = archaeoastronomy
North 14.39038°, East
Introduction: The basic information needed to do
calculations on astronomical events eventually related to an
archaeological site is: Location, date of construction, and orientation.
Also important is information about religious concepts and level of
astronomical knowledge at the time of construction.
We can measure the location and the orientation, but
the time of construction is unknown. The temple was constructed some
time in the 9th century, or maybe even centuries before. From stone
inscriptions we have information about which gods were installed in the
main sanctuary at various epochs, but very limited details about
religious practices. No written information about astronomical knowledge
at the time of construction has come down to us. From inscriptions we
only know that various kings were praised for their Vedic knowledge,
here among astronomy. As the ancient Khmers had close cultural ties to
medieval India we can suppose that Indian astronomical textbooks as the
Surya Siddhanta was in vogue in Kambuja in the end of the first
The only 'hard evidence' we have is artistic
expressions in stone. Like at so many other ancient Khmer temples the
dikpalas (the Guardians of the Cardinal Directions) and the Kala
figure ('time') are depicted on lintels and pediments above the doorways
of the temple. A most interesting art-piece is a frieze depicting the
Navagrahas (the Nine Planetary Deities), which expression and
present location is not known to the author of this paper. We do not
know how these religious expressions were perceived by the ancient
Khmers. Neither do we have any written details about how and when, which
rituals were performed. Hinduism and Buddhism originated in India but
was probably practiced in 'Khmer way' in ancient Kambuja. The Khmer
navagrahas originated in India, but were conceptually very
different. Solar temples are absent, and so are mithunas (erotic
art), which are very common at Shiva temples and Solar temples in India.
North 14.39038°, East 104.68029°
Preah Vihear (Khao Phra Viharn in Thai)
is located on top of the Dangrek
Mountains, on the border between
nowadays Cambodia and Thailand. The temple is located
on Cambodian territory, but easily accessible from Sri Saket Province of
Thailand. The associated baray (reservoir) right north of
the sanctuary is located on Thai territory. The above position is
measured at the main sanctuary.
The construction of Preah Vihear went on continuously from the 9th to the
12th century. The first construction of Preah Vihear is credited
Yasovarman I, who reigned
from 889 to 910, but ''a
son of Jayavarman II (who reigned from 802 to 850) may have founded Preah
Vihear even earlier when he took a fragment of rock from the Lingaparvata
Mountain of Wat Phu in Laos to the site of Preah Vihear'' (ROVEDA,
2000:10). (Wat Phu = Vat Phou).
No inscriptions inform about the year of construction.
The first stone-construction was probably done in the last part of the 9th
century, but the north-south orientated layout of the temple could well
have been in use in older structures made by lighter materials.
Saivite (Bhadreśvara version)
Preah Vihear was a Hindu temple dedicated Shiva in his aspect of
Shikharesvara (Lord of the Summit) and a Bhadresvara linga
was installed in the main shrine.
Prasat Banteay Srey, Prasat Sek Ta Tuy, Prasat Trapang
Khyang from the 10th century were all dedicated to the linga
Tribhuvanamaheśvara, which is the name of the god of Lingapura
(Prasat Koh Ker). The three sanctuaries were made miśrabhoga
(co-participant) of certain revenues with the god Bhadreśvara
(BRIGGS, 1951:138). Bhadresvara, an angry version of Shiva, was
also worshipped at Wat Phu, the cradle of Khmer culture which
flourished in the beginning of the first millennium in what is now
Cambodian 100 riel note.
0.5° true bearing.
Two series of GPS-measurements (conducted by the author in 2004 and 2006)
indicate that the orientation of the temple is not 100%
straight north. Over a distance of 845 m the 'error' is
approximately 8 to 9 m. Compass readings indicate
that other parts of the structure (e.g.. Gopura IV) is
from true cardinal orientation.
Preah Vihear was constructed before the invention of
the compass. Constructing an east-west oriented alignment by use of the sun
is relatively easy, but a north-south line (especially on sloping
terrain) is a little more complicated.
Preah Vihear has an axial layout resembling Prasat Vat
Phou (Laos), Prasat Phnom Scisor (Cambodia), and Prasat Phanom Rung
The stone floors at Preah Vihear have
carved lines following the orientation of the structure. The lines run
from door-step corner to door-step corner or mark the centre-line.
Level IV has an intricate pattern of east-west and north-south lines.
Right: Carved east-west (91°)
centre-line in Gopura IV
related to astronomy:
A Navagraha frieze (the Nine Planetary Deities: Sun, Moon, Mercury,
Venus, Mars, Jupiter, Saturn, Rahu and Ketu) was found in the forest near
the temple (ROVEDA, 2000:24). If the reader knows where this frieze is
exhibited today, the author will be very pleased to be informed, as he is
collecting information on this feature, which has strong astronomical
Dikpalas (Guardians of the Cardinal
Directions) are depicted in the stone carvings of the temple: The Vedic
head god Indra mounted on his vehicle, the elephant Airavata, faces east, the cardinal direction guarded by him.
Yama on his buffalo guards the southern direction. Kubera guards the
western direction and Brahma the northern.
The Kala (literary 'time' and in the
literature also called 'the
time-eating-demon') is represented in the centre of many lintels of the temple.
Solstitial alignment are embedded in
several parts of the layout. The 'solstitial angle' (my phrasing) is
defined as the difference in azimuth angle of the rising sun at equinox
Krishna subduing the Naga Kaliya.
|BRIGGS, L. P. 1951
|The Ancient Khmer
Empire. American Philosophical Society (Philadelphia) vol. 41, 295
pp.. Reprinted by White Lotus Press, Bangkok, 1999.
|FREEMAN, M. 1996
||A Guide to Khmer
Temples in Thailand and Laos. River Books, Bangkok, 1996.
|HIGHAM, C. 2001
||The Civilazation of Angkor, London 2001
|JACQUES, C. and FREEMAN, M. 1999
||Ancient Angkor, River Books Guides,
|ROVEDA, V. 2000
River Books Guides, Bangkok 2000.
Bird-view of Prasat Preah Vihear (from a Cambodian 100 riel note).
Vishnu on Garuda on Kala
12 August 2006
© Asger Mollerup