Mutability of the Heavens and the 1054 Supernova

We referred earlier to the absence of any Western European records for the Crab supernova event. Needham/Ronan (1981, p. 107) and others suggest that this was due to a predisposition in medieval Europe to deny changes in the heavens. Indeed, studies of medieval European chronicles, kept principally by monasteries, have revealed a paucity of observations of such phenomena as novae, sunspots, planetary conjunctions, occultations, and appulses (Stephenson and Clark 1978, p. 7). Because the few cases that are mentioned provide few details, it can be argued that the chroniclers may simply reflect the lack of interest of their times in such phenomena.

However, there is evidence of interest in the behavior of objects in the sky. First, the monasteries of Europe had cause to observe the heavens in order to keep the hours, for pur poses of prayer, fasting, and the order of the day. During the night, an elaborate series of decanal-like asterisms was employed. A manual describing the stars and the process was created by Gregory of Tours for his monastic order (see McCluskey 1990), and there were undoubtedly others.

Second, natural phenomena are frequently, if sporadically, mentioned. Although the monastery chronicles of the British Isles tend to emphasize the deaths of nobles and military action, natural events are also often recorded. Thus, in 1008, the Ulster Annals note that there was severe frost and snow from 6th of the Ides [8th] of January to Easter [Mar 28]; and in 1021, "a shower of wheat" is reputed to have fallen in Osraigi; in 1037, "very wet stormy weather this year" is recorded; in 1047, a great snowfall lasting from the Feast of Mary (in the winter) [Dec. 8] to the Feast of Patrick [Mar. 17], "the like of which was never experienced before and it caused the death of many people and cattle and sea-beasts and birds"; and in 1056, lightning killed three people at one locale and a student at another and broke down "the ancient tree."

Third, there are astronomical records from the 11th century. The age of the Moon is frequently mentioned at the start of the year, for example, the first entry in the Annals of Inisfallen (AI) for the year 1054 reads

The Kalends of January on Saturday, and the eighteenth day of the moon thereon. The one thousandth and fifty-fourth year from the incarnation of Christ. The second year after the bissextile.

Eclipses are recorded in the annals twice during this century, in 1023. In AI, "A solar eclipse this year, i.e., the spring of the black cloud"; and in The Annals of Ulster (AU),

A lunar eclipse on the fourteenth day of the January moon, that is, on Thursday the fourth of the Ides [10] of January. A solar eclipse, moreover, a fortnight afterwards on the twenty-seventh of the same moon.

Comets are reported several times. AU records a comet visible for a fortnight in the autumn season. Comet Halley's 1066 apparition is recorded in European records, as is the 1006 SN, perhaps the most spectacular historical supernova event. These, together with medieval records of meteoritic phenomena, both terrestrial, and, more tellingly, lunar (§5.3.2), give strong evidence of at least some interest in occurrences in the heavens. Moreover, in light of the absence in the Christian world, at this time, of widespread acceptance of Aristotelian ideas, an explanation based on philosophical prejudice appears to us to be inadequate.

As to why records in Europe are so sparse, meterological and geomagnetic records ought to be able to provide some evidence for or against weather conditions as an explanation. A summer of largely cloudy skies at relatively high-latitude locations is entirely believable. Williams (1981) reaches just such a conclusion about Europe and the visibility of SN 1054.

More recently, another explanation has been offered, challenging the July 4 date for the event. Collins, Claspey and Martin (1999) suggest that the date of the supernova occurrence has been misinterpreted in the eastern records, and that the true date was some time in April or early May, based on simulations performed with the Red Shift PC planetar ium software. They argue that a number of overlooked sources (some of which were overlooked because of the widely accepted July 4 date) and otherwise puzzling comments in historical records (mostly regarding the death of Pope Leo IX on April 19, 1054), are all consistent with the 1054 event if the supernova was already in the sky. The Rampona Chronicle (Sorbelli 1905), a derivative of earlier and now apparently lost sources, by Muratori (15th century) lists a bright star ("stella clarissima") occurring during the time of Henry III, i.e., in or after 1055. A date is indicated: "in circuitu prime lune est, 13 Kalendas in nocto inito," (in the orbit/vicinity [our reading] of the (new) Moon early in the night of 13th of the calends), Williams (1981), reproduced in Collins et al. (1999); the original reference was uncovered by Newton (1972, p. 690). Collins et al. argue that this date is 13 kalendas Iuni, or May 20, when the location of the supernova would have been 7° east of the Sun and, thus, near the position occupied by a "new" Moon, i.e., a thin waxing crescent, if the Moon were at this phase. They conclude that the supernova would have been visible against the twilight sky. Collins et al. also cite and discuss one of the Armenian Chronicles (that of Etum Patmich—see Astapovich 1974), and a reinterpretation of the date of a near eastern source (see Brecher et al. 1978; Guidoboni et al. 1972) to place the dates of observation of a bright star phenomenon by these sources on May 14 and April 11, 1054, respectively. Two other references cited by Collins, et al., and discussed by Guidoboni et al. (1972) and by Breen and McCarthy (1995) concern the death of Pope Leo IX on April 19,1054. One reference, the Tractus de ecclesia S. Petri Aldenburgensi (Holder-Egger 1888), refers to a "an orb of extraordinary brilliance" that briefly appeared at the "very hour" of death (Collins et al. 1999, p. 872). Their examination of the oriental sources are equally thorough, and they discuss the visibility issues (see §3.1.2.5) to conclude that a nearby star mentioned in the Chinese chronicles as being seen in the dawn sky on July 4, 1054, could not have been Z Tau, the position of which is on the wrong side in the sources ("several inches southeast of Z Tau," Ho et al. 1972; cited in Collins et al. 1999, p. 874), but more likely b Tau, a slightly brighter star to the north and slightly to the west of Z Tau (see Table 3.1). They also note that the Chief of the Astronomical Bureau (whom Collins et al. refer to as the "chief astrologer"), did not prognosticate about this event until Aug. 27, by which it had faded suffi-cently to be invisible in the daytime sky. The implication is that the astrological concerns of the bureau outweighed any strictly accurate historical record, and consequently, they do not regard the July 4 date as of any great significance; they admit that the association of the death of Leo IX with the bright star could have been stretched somewhat ("with only minimal poetical license") in the interest of ecclesiastical politics, thus, allowing for a May date for the outburst. Note, however, that there continue to be disagreements among the sources. Collins et al. also reexamine the date question of these sources and argue for a late May date for the Japanese observations. If further investigation (especially of the eastern records) supports these conclusions, the mystery of the absence in the West of records of the 1054 supernova will have been solved. But, if their conjecture is correct, we must ask why it took so long for the Chinese astronomers to see

Figure 5.20. The sky of the supernova explosion that produced the Crab Nebula, possibly, on (a) the morning sky of July 5,1054; (b) the evening sky |

of May 20, 1054; and (c) the evening sky of April 13, 1054. The Crab nebula (M1 in the Messier Catalogue) is near Ç Tau. Compare these simulations a with Figure 13.1. Simulations by E.F. Milone with RedShift software.

Figure 5.20. Continued.

Figure 5.20. Continued.

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c g the supernova, if at all, astrological implications notwithstanding, because it would have been easily visible in the evening sky in April or May. Figure 5.20 shows our simulations of the events. Compare the photograph of the Chaco Canyon markings (Figure 13.1) with the positions of the Sun, Moon, and the Crab Nebula, near the star Z Tau. On Apr. 13. 1054, there is a waxing crescent moon in the vicinity of Z Tau. Of course, as we have noted, the pictographic material may have had nothing to do with the supernova, but, as in many archaeoastronomy contexts, the near coincidences are striking.

The records of observations of transient phenomena and the attempts of groups to understand them contribute in basic ways to our understanding of those cultures. Now, we will begin examining archaeoastronomy anew, from a cultural perspective, beginning with Palaeolithic and Mega-lithic peoples, and proceeding through specific geographic regions culture by culture.

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