Applied Historical Astronomy: An Historical Perspective

Kremer R. L. , “The use of Bernard Walther's observations: Theory and observation in early modern astronomy”, Journal for the history of astronomy, xii (1981), 124–32.

Said S. S. and Stephenson F. R. , “Solar and lunar eclipse measurements by medieval Muslim astronomers, I: Background”, Journal for the history of astronomy, xxvii (1996), 259–73; Said S. S. and Stephenson F. R. , “Solar and lunar eclipse measurements by medieval Muslim astronomers, II: Observations”, Journal for the history of astronomy, xxviii (1997), 29–48.

This paper is a revised version of my presentation at the science meeting “Applied Historical Astronomy” which took place as part of the 2003 IAU General Assembly in Sydney on 21 July 2003. I am grateful to F. R. Stephenson for reading my paper when circumstances prevented me from attending the meeting in person. I would also like to thank A. Jones, A. Slotsky, I. A. Steele and F. R. Stephenson for useful discussions during the writing of this paper.

The same questions also need to be asked when attempting to date astronomical reports in order to establish absolute chronologies. See Steele J. M. , “The use and abuse of astronomy in establishing absolute chronologies”, Physics in Canada, lix (2003), 243–8.

Yuan-shih, chaps. 52 and 53. An English translation of these chapters with detailed commentary is being prepared by N. Sivin. In the meantime, see, for example, Steele J. M. , Observations and predictions of eclipse times by early astronomers (Dordrecht, 2000), 197–201 and 275–86.

All citations to the Almagest refer to the translation of Toomer G. J. , Ptolemy's Almagest (London, 1984), unless otherwise noted.

The reports of eclipses in the Almagest have been studied many times going back to at least Simon Newcomb in the 1870s. The most recent study is Steele J. M. , “A re-analysis of the eclipse observations in Ptolemy's Almagest”, Centaurus, xlii (2000), 89–108, which also includes references to earlier work.

On the Babylonian origin of the Mercury and Saturn observations, see Toomer , op. cit. (ref. 6), 453 n. 70 and the text and discussion of scholion number 3 in Jones A. , “A posy of Almagest scholia”, Centaurus, xlv (2003), 69–78.

Toomer , op. cit. (ref. 6), 421.

Those astronomers using earlier Greek observations would often have faced similar problems. See Jones A. , “In order that we should not ourselves appear to be adjusting our estimates … to make them fit some predetermined amount”, forthcoming.

Goldstein B. R. and Bowen A. C. , “The role of observations in Ptolemy's lunar theories”, in Swerdlow N. M. (ed.), Ancient astronomy and celestial divination (Cambridge, Mass., 1999), 341–56, are in my view overly sceptical in arguing that there is no evidence in Greco-Latin sources for such a compilation of eclipse records.

Toomer , op. cit. (ref. 6), 191.

Britton J. P. , Models and precision: The quality of Ptolemy's observations and parameters (New York, 1992), 151.

On the latest known cuneiform tablet (an astronomical Almanac dating to A.D. 75), see Sachs A. J. , “The latest datable cuneiform tablets”, in Eichler B. (ed.), Kramer anniversary volume: Cuneiform studies in honour of Samuel Noah Kramer (Neukirchen-Vluyn, 1976), 379–98. A few bilingual tablets with Greek inscriptions on one side and cuneiform on the other (known as “Greco-Babyloniaca”) have had their Greek inscriptions dated palaeographically to the second or even the third century A.D. See Geller M. J. , “The last wedge”, Zeitschrift für Assyriologie, lxxxvii (1997), 43–95. However, these dates are far from certain, particularly as the Greek inscriptions are on clay, a non-standard material for Greek writing, and the tablets in any case represent work of unusual individual scribes, rather than forming part of the normal scribal tradition.

Steele , op. cit. (ref. 7), 95–97.

Kugler F. X. , Die babylonische Mondrechnung (Frieburg, 1900). See also Aaboe A. , “On the Babylonian origin of some Hipparchian parameters”, Centaurus, iv (1955), 122–5, and Toomer G. J. , “Hipparchus and Babylonian astronomy”, in Leichty E. Ellis M. deJ. and Gerardi P. (eds), A scientific humanist: Studies in memory of Abraham Sachs (Philadelphia, 1988), 353–62.

It now seems clear that much of Babylonian mathematical astronomy was known in the Greco-Roman world. For example, the astronomical papyri recovered from the site of Oxyrhynchus in Egypt reveal that the astrologers practising in that city used Babylonian mathematical astronomy and, crucially, they (or at least the astronomers who provided the tables with which they worked) understood enough of its theoretical basis to adapt the Babylonian schemes to the Egyptian calendar, and perhaps even to develop further the basic systems. See Jones A. , “Studies in the astronomy of the Roman period. III. Planetary epoch tables”, Centaurus, xl (1998), 1–41; Jones A. , “Babylonian lunar theory in Roman Egypt: Two new texts”, in Steele J. M. and Imhausen A. (eds), Under one sky: Astronomy and mathematics in the ancient Near East (Münster, 2002), 167–74; and Britton J. P. and Jones A. , “A new Babylonian model for Jupiter in a Greek source”, Archive for history of exact sciences, liv (2000), 349–73.

Toomer G. J. , “Hipparchus' empirical basis for his lunar mean motions”, Centaurus, xxiv (1980), 97–109.

This translation, more literal that that given in Toomer , op. cit. (ref. 6), 211, was kindly provided by A. Jones. I am particularly indebted to Professor Jones for bring this point to my attention and allowing me to quote his translation.

Babylonian methods of eclipse prediction were directed towards identifying eclipse possibilities and as a result produced many predictions of lunar eclipses that occurred during the day and penumbral eclipses that could not be seen. Often it was known in advance that an eclipse would not be seen, even though the predicted time was during the night, and the scribes indicated that the eclipse prediction was recorded only for record keeping purposes. See Steele J. M. , “The meaning of BAR DIB in Late Babylonian astronomical texts”, Archiv für Orientforschung, xlviii-xlix (2001–2), 107–12.

Toomer , op. cit. (ref. 16). Toomer postulates that Hipparchus visited Babylon; although we have no direct evidence for such a visit it is probably more plausible to assume that a Greek astronomer visited Babylon in order to learn Babylonian astronomy and obtain access to their observational records, than that a travelling Babylonian astronomical scribe would bring copies of observational texts with him.

Goldstein B. R. and Bowen A. C. , “On early Hellenistic astronomy: Timocharis and the first Callippic calendar”, Centaurus, xxxii (1989), 272–93.

For the classification of Babylonian astronomical texts, see Sachs A. J. , “A classification of the Babylonian astronomical tablets of the Seleucid period”, Journal of cuneiform studies, ii (1948), 271–90; Hunger H. , “Non-mathematical astronomical texts and their relationships”, in Swerdlow N. M. (ed.), Ancient astronomy and celestial divination (Cambridge, Mass., 1999), 77–96; and Hunger H. and Pingree D. , Astral sciences in Mesopotamia (Leiden, 1999). On the eclipse records, see Steele , op. cit. (ref. 5), 21–83, and Huber P. J. and De Meis S. , Babylonian eclipse observations 750 BC to 1 BC (Milan, 2004). All of the dated Diaries have been published by Sachs A. J. and Hunger H. , Astronomical diaries and related texts from Babylonia (3 vols, Vienna, 1988–96).

Sachs and Hunger , op. cit. (ref. 22), i, 24.

Hunger H. , Astronomical diaries and related texts from Babylonia, v: Lunar and planetary texts (Vienna, 2001), 4–7.

Published as Texts 2–4 in Hunger , op. cit. (ref. 24). For discussions of the contexts and layout of these tablets, see my appendix in that volume (“The eclipse texts”, pp. 390–9), Huber and Meis De , op. cit. (ref. 22), 1–6, and Walker C. B. F. , “Achaemedid chronology and the Babylonian sources”, in Curtis J. (ed.), Mesopotamia and Iran in the Persian period: Conquest and imperialism 539–331 BC (London, 1997), 17–25. Walker also points to the possibility of this compilation's being the source of the Babylonian eclipse records in the Almagest.

Steele J. M. , “Eclipse prediction in Mesopotamia”, Archive for history of exact sciences, liv (2000), 421–54; Steele J. M. , “A simple function for the length of the Saros in Babylonian astronomy”, in Steele and Imhausen (eds), Under one sky (ref. 16), 405–20.

This was pointed out to me by A. Jones. See Steele , op. cit. (ref. 5), 96.

A modern reconstruction of Ptolemy's canon is provided by Toomer , op. cit. (ref. 6), 11. A detailed discussion of the history of the canon is given by Depuydt L. , “More valuable than all gold: Ptolemy's royal canon and Babylonian chronology”, Journal of cuneiform studies, xlvii (1995), 97–117.

Steele J. M. and Stephenson F. R. , “Lunar eclipse times predicted by the Babylonians”, Journal for the history of astronomy, xxviii (1997), 119–31.

BM 33066 was first published, though not fully understood, by Pinches T. G. , “An astronomical or astrological tablet from Babylon”, The Babylonian and Oriental record, ix (1888), 202–7. A copy was subsequently published by Strassmaier J. N. , Inscriften von Cambyses, König von Babylon (Leipzig, 1890), no. 400. Kugler F. X. , Sternkunde und Sterndienst in Babel, Buch I (Münster, 1907), 64–71, subsequently gave a transliteration, translation and detailed discussion. An improved edition is provided by Hunger , op. cit. (ref. 24), no. 55. A review of both the contents of BM 33066 and previous studies of the tablet is given by Hunger and Pingree , op. cit. (ref. 22), 174–5.

This was first recognized by Oppert J. , “Un texte Babylonien astronomique et sa traduction Greque d'après Claude Ptolémée”, Zeitscrift für Assyriologie, vi (1891), 103–23. For further discussion of this eclipse, see Steele , op. cit. (ref. 5), 97–99, Britton , op. cit. (ref. 10), 58–60, and Huber and De Meis , op. cit. (ref. 22), 95–96.

For example, Fotheringham J. K. , [untitled paper], The observatory, lv (1932), 338–40.

Steele , op. cit. (ref. 7), 98, and op. cit. (ref. 5), 98–99.

Hunger and Pingree , op. cit. (ref. 22), 175.

Kugler , op. cit. (ref. 30). See also Brack-Bernsen L. , Zur Entstehung der babylonischen Mondtheorie (Stuttgart, 1997), 99–103.

Steele, appendix (ref. 25) in Hunger , op. cit. (ref. 24), 392.

Hunger , op. cit. (ref. 24), Text 10.

See in particular Newcomb S. , Researches on the motion of the Moon made at the United States Naval Observatory: Part I. Reduction and discussion of observations of the Moon before 1750 (Washington, 1878), 43, and Britton , op. cit. (ref. 13), 61–63.

Jones , op. cit. (ref. 8).

Jones A. , “A likely source of an observation report in Ptolemy's Almagest”, Archive for history of exact sciences, liv (1999), 255–8.

Jones A. , “An ‘Almagest’ before Ptolemy's”, in Burnett C. Hogendijk J. P. Plofker K. and Yano M. (eds), Studies in the history of the exact sciences in honour of David Pingree (Leiden, 2004), 129–36.

Toomer , op. cit. (ref. 6), 13.

Steele J. M. , “Planetary latitudes in Babylonian mathematical astronomy”, Journal for the history of astronomy, xxxiv (2003), 269–89.

Jones , op. cit. (ref. 8).

Parker R. A. and Dubberstein W. H. , Babylonian chronology 626 BC — AD 75 (Providence, 1956).

Stephenson F. R. , Historical eclipses and Earth's rotation (Cambridge, 1997), 117–18; Steele , op. cit. (ref. 4).

Newton R. R. , “Secular accelerations of the Earth and Moon”, Science, clxvi (1969), 825–31.

Steele , op. cit. (ref. 4).

See, for example, Iwaniszewski S. , “Archaeoastronomical analysis of Assyrian and Babylonian monuments: Methodological issues”, Journal for the history of astronomy, xxxiv (2003), 79–93.

Yoke Peng Ho , The astronomical chapters of the Chin Shu (Paris, 1966), provides an English translation of the T'ien-wen Chih from the Chin dynastic history.

See, for example, the discussions by Yi-Long Huang , “Astronomie e astrologia”, in Chelma K. (ed.), Storia della scienza, ii, sezione 1: La scienza in Cina (Rome, 2001), 167–70, and Lloyd G. E. R. , The ambitions of curiosity: Understanding the world in ancient Greece and China (Cambridge, 2002), 34–35.

Bielenstein H. , “An interpretation of the portents in the Ts'ien-han-shu”, Bulletin of the Museum of Far Eastern Antiquities, xxii (1950), 127–43. See also Bielenstein H. , “Han portents and prognostications”, ibid., lvi (1984), 97–112, and Eberhard W. , “The political function of astronomy and astronomers in Han China”, in Fairbank J. K. (ed.), Chinese thought and institutions (Chicago, 1957), 33–70.

Foley N. , “A statistical study of the solar eclipses recorded in Chinese and Korean history during the pre-telescopic era”, M.Sc. dissertation, University of Durham, 1989.

Sivin N. , “Cosmos and computation in early Chinese mathematical astronomy”, T'oung Pao, lv (1969), 1–73.

See, for example, the letter by Zhentao Xu, D. W. Pankenkier and Yatiao Jiang (responding to my review of their East Asian archaeoastronomy (Amsterdam, 2000)) in Physics today, lv/9 (September 2002), 82–83, and my reply in the same issue.

Stephenson F. R. , “Eclipse records in early Korean history: The Koryo-sa”, in Ansari S. M. R. (ed.), History of oriental astronomy (Dordrecht, 2002), 237–43; Yonggi Kim , “Statistics of astronomical records in Korea during AD 1200–1450”, in Il-Seong Nha and Stephenson F. R. (eds), International conference on oriental astronomy from Guo Shoujing to King Sejong (Seoul, 1997), 143–58.

Bailey M. E. Clube S. V. M. and Napier W. M. , The origin of comets (Oxford, 1990). See also Bailey M. E. , “Sources and populations of near-Earth objects: Recent findings and historical implications”, in Peiser B. J. Palmer T. and Bailey M. E. (eds), Natural catastophies during Bronze Age civilisations (Oxford, 1998), 10–20.

Bailey Clube and Napier , op. cit. (ref. 57), Figures 4.3–4.5.

Bailey Clube and Napier , op. cit. (ref. 57), 75. This theme is developed even further in Clube S. V. M. , “An exceptional cosmic influence and its bearing on the evolution of human culture as evident in the apparent early development of mathematics and astronomy”, Astrophysics and space science, cclxxxv (2003), 521–32.

Even less founded is the claim made in Bailey Clube and Napier , op. cit. (ref. 57), 37 that the varying number of astronomical cuneiform texts from Babylon as graphed in one of Neugebauer's publications may reflect varying degrees of meteoric activity. First of all, these texts are texts of mathematical astronomy and have nothing directly to do with observing the sky; in some cases they contain calculations for periods up to nearly a century before or after their date of composition. Secondly, the number of these texts per decade given in Neugebauer's graph reflects not how many were composed but how many have been preserved, which is at the mercy of archaeological chance. Furthermore, the graph reflects only texts that are datable, which will tend to result in clusters of texts; see my comments in Steele J. M. , “Some lunar ephemerides and related texts from Babylon”, in Wunsch C. (ed.), Mining the archives: Festschrift for Christopher Walker (Dresden, 2002), 293–318. We should also not underestimate possible biases in the chronological distribution of published tablets caused by the particular interests of modern scholars.

Studies of historical records of sunspots in order to investigate changes in solar activity face the same problem. See Eddy J. A. Stephenson F. R. and Yau K. K. C. , “On pre-telescopic sunspot records”, Quarterly journal of the Royal Astronomical Society, xxx (1989), 65–73.

Stephenson F. R. and Green D. A. , Historical supernovae and their remnants (Oxford, 2002).

Stephenson , op. cit. (ref. 46); Stephenson F. R. and Morrison L. V. , “Long-term fluctuations in the Earth's rotation: 700 BC to AD 1990”, Philosophical transactions of the Royal Society of London, A cccli (1995), 165–202. Investigating the Earth's rotation is unquestionably the oldest — and most important — problem in applied historical astronomy.

See, for example, Steele J. M. , “On the use of the Chinese Hsuan-ming calendar to predict the times of eclipses in Japan”, Bulletin of the School of Oriental and African Studies, lxi (1998), 527–33, which deals with medieval Japanese eclipse records, and Shi Yunli , “Eclipse observations made by Jesuit astronomers in China: A reconsideration”, Journal for the history of astronomy, xxxi (1999), 134–47, which looks at a number of seventeenth-century eclipse records from China.

Huber P. J. , “Early cuneiform evidence for the existence of the planet Venus”, in Goldsmith D. (ed.), Scientists confront Velikovsky (Ithica, 1977), 117–44, and Huber P. J. , Astronomical dating of Babylon I and Ur III (Malibu, 1982). See also Swerdlow N. M. , The Babylonian theory of the planets (Princeton, 1998), 39–50.

Stephenson F. R. , “A re-investigation of the ‘double dawn’ event recorded in the Bamboo Annals”, Quarterly journal of the Royal Astronomical Society, xxxiii (1992), 91–98, and Keenan D. J. , “Astro-historiographic chronologies of early China are unfounded”, East Asian history, xxiii (2002), 61–68.

Pang K. D. Yau K. K. and Chou Hung-Hsiang , “Astronomical dating and statistical analysis of ancient eclipse data”, in Ansari S. M. R. (ed.), History of oriental astronomy (Dordrecht, 2002), 95–119, which builds upon work published in Pang K. D. Yau K. K. Chou Hung-Hsiang and Wolf R. , “Computer analysis of some ancient Chinese sunrise eclipse records to determine the Earth's rotation rate”, Vistas in astronomy, xxxi (1988), 833–47. Other authors who have used the “double dawn” eclipse for dating include the Xia-Shang-Zhou Chronology Project; see Ci-Yuan Liu , “Astronomy in the Xia-Shang-Zhou Chronology Project”, Journal of astronomical history and heritage, v (2002), 1–8.

Huber P. J. , “Dating by lunar eclipse omina with speculations on the birth of omen astrology”, in Berggren J. L. and Goldstein B. R. (eds), From astral omens to statistical mechanics: Essays presented to Asger Aaboe (Copenhagen, 1987), 3–13. See also Huber P. J. , “Astronomical dating of Ur III and Akkad”, Archiv für Orientforschung, xlvi-xlvii (1999–2000), 50–79.

Hunger H. , “Uses of Enuma Anu Enlil for chronology”, Akkadica, cxix-cxx (2000), 155–8. See also the comments by Rochberg F. , “Empiricism in Babylonian omen texts and the classification of Mesopotamian divination as science”, Journal of the American Oriental Society, cxix (1999), 559–69.

Stephenson , op. cit. (ref. 46), 304–5.

Steele , op. cit. (ref. 5), 204–8.

Steele , op. cit. (ref. 5), 181.

John Fermor's work is reported in Brown D. Fermor J. and Walker C. B. F. , “The water clock in Mesopotamia”, Archiv für Orientforschung, xlvi-xlvii (1999–2000), 130–48, and Fermor J. and Steele J. M. , “The design of Babylonian waterclocks: Astronomical and experimental evidence”, Centaurus, xlii (2000), 210–22. Dennis Duke is preparing a paper describing his work with the Ptolemaic armillary sphere.

Ci-Yuan Liu and Xiao-Lu Zhou , “The sky brightness when the rising sun is in eclipse”, Chinese astronomy and astrophysics, xxiii (1999), 249–57.

Mossman J. M. , “A comprehensive search for sunspots without the aid of a telescope, 1981–1982”, Quarterly journal of the Royal Astronomical Society, xxx (1989), 59–64.

Doggett L. E. and Schaefer B. , “Lunar crescent visibility”, Icarus, cvii (1994), 388–403. A very useful overview of Doggett and Schaefer's work in the context of investigating Egyptian chronology is given by Wells R. A. , “The role of astronomical techniques in ancient Egyptian chronology: The use of lunar month lengths in absolute dating”, in Steele and Imhausen (eds), Under one sky (ref. 16), 459–72.