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Kepler's View of the Star of Bethlehem and The Babylonian Almanac for 7/6 B.C.

  • A. J. Sachs and C. B. F. Walker

Modern discussion of what identifiable astronomical phenomenon lies behind the biblical story of the so-called Star of Bethlehem was effectively begun by the astronomer Johann(es) Kep(p)ler (1571–1630), mathematician to Rudolph II, Holy Roman Emperor 1576–1612. In the years 1604–5 a supernova appeared in the constellation Ophiuchus and excited considerable discussion in Europe. Kepler kept a detailed record of his observations of the star. In the preceding year, 17 December 1603, at Prague he had also witnessed a conjunction of the planets Jupiter and Saturn with Mars moving into the vicinity soon after, which interested him in his capacity as court astrologer. The supernova appeared in the neighbourhood of these three planets. In medieval times the conjunction of Jupiter and Saturn, known as the “great conjunction” (recurring only once every 19·86 years on average), was regarded as of great astrological significance. Kepler calculated that a similar conjunction with Mars moving into the vicinity soon after had occurred in the year 7 B.C. = Julian year 39. On that occasion the conjunction had been a triple conjunction, a very much rarer event than the normal single conjunction.

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1 Matthew 2, 1–12.

2 Kepler's works are edited by Max Caspar in five volumes, Kepler Johannes, Gesammelte Werke, I–V (Munich, 19381953). The volumes relevant to the present article are I, pp. 147–390 (De Stella Nova; Prague and Frankfurt, 1606) and V, 5–126 (De Anno Natali Christi; Frankfurt, 1614), cited here as Kepler I and Kepler V.

3 Clark D. H. and Stephenson F. R., The historical supernovas (Oxford, 1977), 191206. The constellation Ophiuchus was also known in Kepler's time as Serpen tarius.

4 Kepler I, 157–65 and 208–17.

5 Kepler I, 197 ff.

6 Kepler used a Julian era, starting with the introduction of the Julian calendar on 1 January 45 B.C.

7 The three conjunctions of Jupiter and Saturn occurred on 27 May, 6 October, and 1 December 7 B.C. according to modern calculations. See note 23 below.

8 Velificatio seu Theoremata de anno ortus ac mortis Domini, deque universa Jesu Christi in came oeconomia (Graz, 1605). Known to us only by title from Kepler I, 359 and 445; copies are preserved in the Österreichische Nationalbibliothek, Vienna, and the Steiermarkische Landesbibliothek, Graz (information courtesy Miss I. Seybold).

9 Bickerman E. J., Chronology of the Ancient World (London, 1968), 81; Finegan J., Handbook of Biblical Chronology (Princeton, 1964), 132.

10 For Kepler's original statement of this view see Kepler I, 279–80 (and 359–60); it is repeated in Kepler V, 95–7 (see also 298–9). Part of Kepler V, 96–7 is translated into German in Kritzinger H. H., Der Stern der Weisen (Gütersloh, 1911), 44–5.

11 The literature on the subject is vast and ever increasing. The most useful bibliography is to be found in Hughes D., The Star of Bethlehem mystery (London, 1979), which is a comprehensive discussion of the various theories and the astronomical phenomena. The following works, consulted in the preparation of the present article, explicitly or implicitly ascribe the planetary conjunction hypothesis to Kepler: (1) Maunder E. W., The astronomy of the Bible (London, 1908), 396–7. (2) The Christmas star (Anon., Morrison Planetarium; California, 1954), 1214. (3) Keller W., The Bible as history (English edition; London, 1956), 328–36. (4) Montefiore H. W., “Josephus and the New Testament”, Novum Testamentum 4 (1959), 140–8. (5) J. Finegan, op. cit., 245–6. (6) d'Occhieppo K. Ferrari, “Jupiter und Saturn in den Jahren -125 und -6 nach babylonischen Quellen”, Osterreichische Akademie der Wissenschaften Sitzungsberichte, Abt. II, 173 (Wien, 1964), 343–76 (see also Quarterly Journal of the Royal Astronomical Society 19 (1978), 517–20). (7) Clark D. H., Parkinson J. H., Stephenson F. R., “An astronomical re-appraisal of the Star of Bethlehem”, QJRAS 18 (1977), 443–9. (8) D. Hughes, op. cit., 96–100 (see also his earlier article in Nature 264 (1976), 513–17 and the resulting correspondence in Nature 268 (1977), 565–7).

12 Ideler L., Handbuch der mathematischen und technischen Chronologie II (Berlin, 1826), 399401.

13 Caspar M., Kepler (English edition; London and New York, 1959, translated and edited by C. Doris Hellman), 156. See also Caspar's Nachbericht in Kepler I, 445. Correct accounts of Kepler's view are also given by Kritzinger H. H., Der Stern der Weisen (Gütersloh, 1911), 34–5 and 44–5, Schaumberger J., “Textus cuneiformis de Stella Magorum?”, Biblica 6 (1925), 444–9, and Mosley J., “When was that Christmas star?”, Griffith Observer (Los Angeles), 12 1980, 29.

14 Caspar M., Kepler, 153. See also Schlaumberger J., Biblica 7 (1926), 300 n. 1, and 24 (1943), 165 f.

15 Not 805 years as stated by Finegan, op. cit., 245. Ideler, whom Finegan cites, gives the figure 794 years 4 months 12 days. The misunderstanding is taken a stage further by Hughes, op. cit., 96–7, perversely correcting the chronological scheme devised by Kepler (Kepler I, 183).

16 Kepler I, 279.

17 Luard H. R., Annales Monastici IV (London, 1869), 491: “Saturnus et Jupiter eodem anno erant in conjunctione in Aquario, quod non contigit post Incarnationem, nee multo tempore secundum astronomicos iterum eveniet ut aestimatur.”

18 Newton R. R., Mediaeval chronicles and the rotation of the earth (Baltimore and London, 1972), 691; D. H. Clarke et al., op. cit., 447; Botley C. M., Nature 268 (1977), 565; D. Hughes, op. cit., 94–6.

19 That conjunction took place on 31 December 1285 at 308° in Aquarius, while the 7 B.C. conjunctions took place between 345° and 351° in Pisces. See Tuckerman's tables cited in note 23 below.

20 Ideler, loc. cit.

21 Kepler I, 279.

22 Rev.Pritchard C., “On the conjunctions of the Planets Jupiter and Saturn in the years 7 B.C., 66 B.C., and A.D. 54”, Memoirs of the Royal Astronomical Society, 25 (1857), 119–24 (summarized in the Monthly Notes of the R.A.S., 16 (1856), 215–16).

23 Tuckerman B., Planetary, Lunar, and Solar Positions 601 B.C. to A.D. 1 (= Memoirs of the America Philosophical Society, 56; Philadelphia, 1962), 330. Similar tables for A.D. 2 to A.D. 1649 are published in M.A.P.S. 59 (1964). For other similar tables see Stahlman W. D. and Gingerich O., Solar and Planetary Longitudes from –2500 to + 2000 (University of Wisconsin Press, 1963).

24 See note 11 above.

25 The data on the angular separation of the planets is presented in the form of a graph by Clark et al., op. cit., 447, and Hughes, op. cit., 115. Pritchard, op. cit., reached the same conclusion.

26 Kritzinger, Ferrari d'Occhieppo, and Hughes. See notes 11 and 13 above. Pritchard and Schaumberger reject the idea without proposing alternative astronomical hypotheses.

27 Sinott R., Sky and Telescope, 36, no. 6 (Cambridge, Mass., 12 1968), 384–6; Mosley J., Griffith Observer, 12 1980, 29.

28 Clarke et al., QJRAS 18 (1977), 443–9, and The Historical Supernovae, 40–56. The idea goes back to Foucquet J. F., Tabula Chronologica Historiae Sinicae (Rome, 1729). See also Munter F., Der Stern der Weisen (Copenhagen, 1827), 29; Lundmark K., “The Messianic ideas and their astronomical background”, Actes du VIIe Congrès International des Sciences (Jerusalem, 1953), 436–49; Montefiore, op. cit., 143–4; Finegan, op. cit., 246–8; Hughes, op. cit., 148–63; Cullen C., QJRAS 20 (1979), 153–9, correcting the data of Clarke et al. on the supposed Korean references.

29 Montefiore, op. cit., 142 n. 6; Finegan, op. cit., 246; Clarke et al., op. cit., 448; Hughes, op. cit., 120–3, 128, 159–60, 190; and especially K. Ferrari d'Occhieppo, op. cit., passim.

30 Journal of Cuneiform Studies 2 (1948), 271–90; see especially 277–80.

31 The latest dateable cuneiform texts’, Kramer Anniversary Volume, Alter Orient und Alte Testament 25 (Neukirchen, 1976), 379–98.

32 Pinches T. G. and Strassmaier J. N., Late Babylonian astronomical and related texts, edited by Sachs A. J. (Providence, R.I., 1953), nos. 1118–19; hereafter abbreviated as LBAT, 1118, etc.

33 LBAT, 1117.

34 Bibliotheca Mesopotamica 2 = Babylonian Planet Omens (Malibu, Ca., 1975–).

35 Bibliotheca Mesopotamica 2/2, 43 III 13–13b,45 IV 5–5a, 49 VI 5–5a.

36 E.g. Reiner E., Bibliotheca Mesopotamica 2/1 = Babylonian Planetary Omens 1, The Venus tablets of Ammisaduqa (Malibu, Ca., 1975).

37 LBAT, 1193–5.

38 Zeitschrift fur Assyriologie 36 (= NF 2) (1925), 6670.

39 Negative VAN 3321.

40 Sachs , JCS 2, 271–3.

41 ZA 36 (= NF 2), 66.

42 Biblica 6, 446 and Analecta Orientalia 12, 279–82. Finegan, op. cit., 246, and Hughes, op. cit., 128, still give Sippar as the provenance; Clarke et al. and Ferrari d'Occhieppo are aware of the correct provenance.

* A. J. Sachs prepared the transliteration and translation of the Babylonian texts and made the necessary astronomical computations. C. B. F. Walker collated all the original texts (VAT 290 + 1836 from a photograph), wrote the introduction, and is responsible for the final form of the article. We regretfully record that Professor Sachs died in April 1982 while this article was awaiting publication.

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