On the Orientation of Old Kingdom Egyptian Pyramids

Spence K. , ‘Ancient Egyptian chronology and the astronomical orientation of pyramids’, Nature, vol. 408 (2000), 320–4. Spence's work has proved highly controversial, with serious debates between scholars, and her proposals have been severely questioned. See for example H. Thurston, ‘Aligning Giza: Astronomical orientation of the Great Pyramid’, Griffith observer, Sept. 2001, in press; Maravelia Alice-Amanda , ‘L'horizon astral de Khéops: Archéoastronomie, Égyptologie … et quelques scénarios de science-fiction’, Tôzai, v (2000 [2001]), 1ff; and Lamberti C. , ‘Mizar, Kochab et la piramide di Cheope’, L'astronomie, ccxvii (2001), 32–38.

See e.g. Petrie W. M. F. , The pyramids and temples of Gizeh (London, 1883), or Zaba Z. , L'orientation astronomique dans l'ancienne Egypte et la précession de l'axe du monde (Prague, 1953). Apart from those of the Fourth Dynasty, which are entirely built of stone, most of the pyramids are in very bad condition and it will never be easy to obtain accurate measurements of their orientation. A good alternative would be to measure the mortuary temples that adjoin most of the pyramids.

For the most accurate measurements, see Dorner J. , ‘Die Absteckung und astronomische Orientierung ägyptisher Pyramiden’, Ph.D. thesis, University of Innsbruck, 1981, or Spence , op. cit. (ref. 1), Table 1.

Only Tycho Brahe, in the sixteenth century, with the sophisticated instruments he built in Uraniborg, is reputed to have obtained a 1′ precision for stellar position measurement prior to the use of the telescope in astronomical observations. I believe, on the basis of my own experience, that it would have been extremely difficult for an Egyptian ‘astronomer’ to obtain a precision better than two or three arc minutes.

See Petrie , op. cit. (ref. 2).

See Smyth Piazzi Charles , Our inheritance in the Great Pyramid (London, 1890), and Proctor R. A. , Myths and marvels of astronomy (New York, 1889).

For a good review of the different proposals see Gallo C. , L'astronomia egizia (Padua, 1998). See also Isler M. , ‘An ancient method of finding and extending direction’, Journal of the American Research Center in Egypt, xxvi (1989), 191–206, and Pogo A. , ‘The astronomical ceiling decoration in the tomb of Senmut’, Isis, xviii (1932), 301–25. Pogo proposed Mizar (ζ UMa) as the star observed at culmination. Romieu proposed Alkaid (η UMa).

See Gallo , op. cit. (ref. 7), 77–90.

See Belmonte J. A. , Las leyes del cielo (Madrid, 1999), 275.

Haack S. C. , ‘The astronomical orientation of the Egyptian pyramids’, Archaeoastronomy, no. 7 (1984), S119–25.

Edwards I. E. S. , The pyramids of Egypt, 3rd edn (Harmondsworth, 1993). See also Maravelia , op. cit. (ref. 1): ‘Discrepancies and diminishing precision in the orientation of pyramids … are explained as due to random and systematic errors during the observations of ancient Egyptian priest-astronomers’ and not as a systematic trend.

See Spence , op. cit. (ref. 1), or Schilling G. , ‘The star-pyramid connection’, Mercury, xxx (2001), 28–31. Spence's calculations have been questioned by Dennis Rawlins and Keith Pickering who have argued about a small discrepancy between the difference of azimuth at the horizon — The actual astronomical datum — And the angle of the cord connecting the simultaneous vertical crossing of the stars and the Pole as calculated by a colleague on behalf of Spence, see Thurston, op. cit. (ref. 1). It is also worth mentioning that Robert Bauval claimed that he had already published this idea without having this recognized by Spence ( Bauval R. Gilbert A. , El misterio de Orión (Spanish transl. of The Orion mystery, Madrid, 1995), Fig. 15a). However, this figure shows the meridian connecting Kochab and Mizar across the Pole merely by chance, and no direct claim that this was involved in the actual method of orienting the pyramids is to be found in the corresponding text. In fact the figure related to the orientation of one of the airshafts of the Queen's chamber of the pyramid of Khufu.

These dates are too late for any compromise with the vast majority of Egyptologists. See e.g. von Beckerath J. , Cronologie des pharonischen Ägypten (Mainz, 1997). However James might be very happy with such a proposal. See James P. Thorpe I. J. Kokkinos N. Morkot R. Frankish J. , Siglos de oscuridad (Spanish transl. of Centuries of darkness, Madrid, 1993), 216–50.

The date of the reign of Qa', the last king of the First Dynasty, has been radiocarbon dated at 2925 ± 110 b.c. See Hassan M. , ‘The Predynastic of Egypt’, Journal of world prehistory, ii (1988), 135–85. Alternatively, Rawlins and Pickering (see ref. 12) propose, without contextual evidence, to use Thuban and 10 Dra, offering a new chronology centred on 2627 b.c.

Faulkner R. O. , The ancient Egyptian Pyramid Texts (Oxford, 1969).

See Belmonte J. A. , ‘The decans and the ancient Egyptian skylore: An astronomer's approach’, Proceedings of the INSAP III Meeting, Palermo, 31 December 2000–6 January 2001, Memorie della Societa Astronomica Italiana (in press), and references therein. Other interpretations can be found in Böker R. , ‘Über Namen und Identifizierung der ägyptischen Dekane’, Centaurus, xxvii (1984), 189–217, and in the masterpiece: Neugebauer O. Parker R. A. , Ancient Egyptian astronomical texts (3 vols, Providence, 1960–69).

Brugsch H. , Thesaurus inscriptionum aegyptiacarum (Leipzig, 1883–91). See also Faulkner R. O. , ‘The king and the star-religion in the Pyramid Texts’, Journal of Near Eastern studies, xxv (1966), 153–61.

I am also of that opinion which locates the Field of Offerings, where the Imperishable Stars alight, either north of the ecliptic (Rolf Krauss, personal communication) or north of the Milky Way. See also Davis V. L. , ‘Identifying ancient Egyptian constellations’, Archaeoastronomy, no.9 (1985), S102–4.

See Locher K. , ‘Probable identification of the ancient Egyptian circumpolar constellations’, Archaeoastronomy, no. 9 (1985), S152–3.

Belmonte J. A. , ‘The Ramesside star clocks and the ancient Egyptian constellations’, in Proceedings of the SEAC 2001 meeting on symbols, calendars and orientations, Stockholm, 27–30 August (in press). See also Clagett M. , Ancient Egyptian science, ii: Calendars, clocks and astronomy (Philadelphia, 1995).

Krupp E. C. , Echoes of the ancient skies (New York, 1983), 211–13. See also Roth A. M. , ‘Fingers, stars and the opening of the mouth: The nature and function of the nṭrwi-blades’, Journal of Egyptian archaeology, lxxix (1993), 57–79.

Brugsch , op. cit. (ref. 17). See also Krupp , op. cit. (ref. 21), 26, and Leitz C. , Studien zur Ägyptischen Astronomie (Ägyptologische Abhandlungen, 49; Wiesbaden, 1991).

Faulkner R. O. , A concise dictionary of Middle Egyptian (Oxford, 1988).

Krupp , op. cit. (ref. 21), 126.

See Gallo , op. cit. (ref. 7), 82. Imhotep was ‘First of the Observers’, the title of the high-priest of the sun god Re at Heliopolis.

Trimble V. , ‘Astronomical investigations concerning the so-called air shafts of Cheops' pyramid’, Mitteilungen des Institut für Orientforschung, x (1964), 183–7.

The data obtained by Rudolf Gatenbrick are reported by Bauvall Gilbert , op. cit. (ref. 12).

See Belmonte , op. cit. (ref. 16) and references therein, including: Locher K. , ‘New arguments for the celestial location of the decanal belt & the origins of the s3h hieroglyph’, Proceedings of the Oxford V Conference on cultural aspects of astronomy (Sante Fe, 2001, in press).

See Gallo , op. cit. (ref. 7), 85–86.

The most widely accepted chronology for the Old Kingdom, according to Spence (private comm.) is that from von Beckerath, op. cit. (ref. 13). However, earlier dates have been proposed, for example by Malek J. , ‘The Old Kingdom’ in The Oxford history of Egypt, ed. by Shaw I. (Oxford, 2000), 89–117, and by Clayton P. A. , ‘Crónica de los Faraones’ (Madrid, 1996), 30. The lowest dates in the literature can be found in the outdated ‘Egipto: Dioses, templos y faraones’, Atlas culturales del mundo, by Baines J. Malek J. (Barcelona, 1988), 36.

Tefnin R. , ‘Reflexiones sobre la imagen egipcia antigua: La medida y el juego’, Arte y sociedad del antiguo Egipto, ed. by Molinero M. A. Sola D. (Madrid, 2000), 15–36. See also Image 1.9.

This seven-point star and the inverted horns of a bull are often assumed to be related in some way to the seven stars of the Bull's Thigh, the Egyptian Meskhetiu. See e.g. Krupp , op. cit. (ref. 21), 25–26.

Despite the hundreds of merkhets that must have existed throughout Egyptian history, taking into account that they were used to measure the hours of the night in every temple, those remaining can be counted on the fingers of one hand. It is perfectly possible, then, that no ‘Seshat instrument’ has survived, especially if they were not used after the Old Kingdom, when the device became simply the ritualized hieroglyphic sign of the goddess.

See Von Beckerath , op. cit. (ref. 13), and Gardiner A. H. , The royal canon of Turin (Oxford, 1987).

Krauss R. , ‘The length of Sneferu's reign’, Journal of Egyptian archaeology, lxxxii (1996), 43–50.

Stadelman R. , ‘Beiträge zur Geschičhte des Alten Reisches: Die Länge der Regierung des Snofru’, Mitteilungen des Deutsches Archäologisches Institut, Abteilung Kairo, xliii (1986), 229–40.

Krauss , op. cit. (ref. 35).

Not only the pyramid of Wenis, but also the pyramids of the Middle Kingdom with known orientation data (see Spence , op. cit. (ref. 1) and references therein) must have been aligned either by another method or with another pair of stars. Curiously, the pyramid of Wenis might have been aligned (with its error of 17½° east of north) on the simultaneous vertical transit of the handles of the Two Adzes, the stars Alkaid (η UMa) and Polaris (α UMi), with the former in lower culmination, in 2400 ± 30 b.c., a date in perfect agreement with the chronology we are dealing with in this paper. It would be interesting to have accurate measurements for the rest of the Fifth, Sixth, Eighth and Twelfth Dynasty pyramids in order to analyse the problem deeply.

The step pyramid of Djeser, with an estimated deviation of 3° west of north, was certainly not aligned by our method, which would have yielded a deviation of nearly ½°.

A measurement of the substructure of the ‘Unfinished’ Pyramid at Zawiyet el Aryan, often attributed to an unknown transitory king of the Fourth Dynasty because of its structural similarities to the pyramid of Djedefre, would also prove to be a good test.

The book by Lockyer J. N. , The dawn of astronomy (London, 1894), was critized by the Egyptologists of his time because of the numerous historical errors and mythological speculation presented in it.

A renewal of interest in Egyptian archaeoastronomy was generated by the works of Hawkins G. S. , Beyond Stonehenge (New York, 1973) and ‘Astroarchaeology: The unwritten evidence’, Archaeoastronomy in pre-Columbian America, ed. by Aveni A. (Austin, 1975), 131–62. For more recent work, see Wells R. A. , ‘Sothis and the Satet Temple on Elephantine: A direct connection’, SAK, xii (1985), 255–302; Krupp , op. cit. (ref. 21); and Belmonte , op. cit. (ref. 9), 136–71. Even Egyptian scholars are now interested in these issues; see the work of the astronomer M. Shaltout, ‘Sun perpendicularity on Abu Simbel Temple phenomenon’ (in press; preprint available at <mamshaltout@frcu.eun.eg>).