756 CE BY NO MEANS MILD QUAKE(S)

March 756 CE

by Jefferson Williams

Introduction & Summary

The By No Means Mild earthquake gets its name because in some translations of Theophanes he describes it as an earthquake that was "by no means mild". Pseudo-Dionysius of Tell-Mahre, who appears to be a contemporaneous source, describes the same earthquake but provides more details than Theophanes - stating that three villages on the north Mesopotamian Khabur River collapsed and many other places in Jazira were destroyed. Theophanes merely specifies that the earthquake struck Syria and Palestine. The earthquake likely struck in March 756 CE. Although calendaric inconsistencies in Thephanes' entry indicate it could have struck in the years 756, 757, 758, or, less likely, 759 CE, Halley's comet appeared in 760 CE and was described by Pseudo-Dionysius of Tell-Mahre and Theophanes 4 years after their earthquake accounts - thus fixing the date of this earthquake to 756 CE. There is a slight disagreement between Pseudo-Dionysius and Theophanes on the exact day. Pseudo-Dionysius says it struck on the 3rd of March while Theophanes says it struck on the 9th. Pseudo-Dionysius also says that it struck in the middle of the night and on a Tuesday. Arabic sources speak of an earthquake which struck around 756 CE in Mopsuestia which could be related to the event described by Pseudo-Dionysius of Tell-Mahre and Theophanes. There is also a Muslim tradition that the Al-Aqsa Mosque in Jerusalem was destroyed by an earthquake that, based on textual sources, struck between 754 and 785 CE although a more likely date range may be between 754 and 775 CE. Although some have attributed this seismic destruction to the By No Means Mild Quake, this attribution has two problems. The epicentral region that can be derived from Pseudo-Dionysius of Tell-Mahre's account seems too far away to have destroyed Al Aqsa and the date for the By No Means Mild Quake may be too early.

Intensity Estimates

Textual Evidence

Text (with hotlink)	Original Language	Biographical Info	Religion	Date of Composition	Location Composed	Notes
Pseudo-Dionysius of Tell-Mahre	Syriac	Biography	Eastern Christian	750-775 CE	Zuqnin Monastery	Pseudo-Dionysius of Tell-Mahre described a powerful, terrible and dreadful earthquake on Tuesday 3 March 756 CE which took place in the middle of the night in the land of the Jazira. Three villages on the Khabur collapsed, and many people perished inside them, like grapes in a wine press. Many other places were also destroyed by this earthquake. 3 March 756 CE fell on a Wednesday.
Pseudo-Dionysius of Tell-Mahre, Theophanes, and the Comet of 760 CE						Halley's Comet appeared in May and June of 760 CE and was both observed and recorded by Pseudo-Dionysius of Tell-Mahre and Theophanes. This precise time marker can be used to anchor the year of the By No Means Mild Quake in both accounts to 756 CE.
Article by Neuhauser et al (2021) on the Comet of 760 CE						Neuhauser et al (2021) identified Halley's Comet (1P/Halley) as the comet described by Pseudo-Dionysius of Tell-Mahre (Chronicle of Zuqnin), Theophanes, Agapius of Menbj, Nu'aym ibn Ḥammmad, Michael the Syrian, and Chinese, Japanese and Korean sources. They performed astronomical calculations (least squares fitting of Keplerian orbital solutions) to fit "corrected" historical reports paying close attention to the month and day of astronomical observations in the sources. Despite chronological inconsistencies (year and month) among the various sources (possibly due to scribal errors) which they had to "correct", they identified the comet as 1P/Halley and obtained a precise perihelion time (760 May 19.1 ± 1.7) and an inferior conjunction between the comet and Sun (June 1.8) which is about one day different from a previously published orbit (760 May 31.9, Yeomans and Kiang, 1981). Based on their orbital model and philological arguments, Neuhauser et al (2021:7) suggest that Pseudo-Dionysius drew the comet, 3 stars (Ari), and two planets (Mars and Saturn) in his text in the early morning (before sunrise) on 25 May 760 CE.
Theophanes	Greek	Biography	Orthodox (Byzantium)	800-814 CE	Vicinity of Constantinople	Theophanes (c. 758/60-817/8) wrote that on 9 March 756 CE an earthquake that was by no means mild struck Palestine and Syria.
al-Masudi	Arabic	Biography	Muslim - Shi’ite	mid-10th century CE	Egypt ?	al-Masudi wrote that Caliph al-Mahdi (r. 775-785 CE) rebuilt Jerusalem, which had been devastated by earthquakes
Muslim Writers - Description of Syria including Palestine by al-Maqdisi	Arabic	Biography	Muslim	ca. 985 CE	Jerusalem ?	In "Description of Syria including Palestine", native Jerusalemite al-Maqdisi wrote that earthquakes (plural) threw down the main building of Al Aqsa Mosque, except for the Mihrab, in the days of the Abbasids (who began their rule on 25 Jan. 750 CE). The Caliph of the day financed rebuilding by having each Governor build a colonnade. The days of the Abbasides dates this to after 25 January 750 CE.
Muslim Writers - The Best Divisions in the Knowledge of the Regions by al-Maqdisi	Arabic	Biography	Muslim	ca. 985 - 990 CE	Jerusalem ?	In his famous book "The Best Divisions in the Knowledge of the Regions", thought to have been written after "Description of Syria including Palestine", native Jerusalemite al-Maqdisi wrote that in the days of the ‘Abbäsides an earthquake [singular] occurred which threw down most of the main building [Al Aqsa Mosque]; all, in fact, except the part around the mihrab. The days of the Abbasides dates this to after 25 January 750 CE and since the destruction is described as total (the entire mosque except for the mihrab) and not just two walls, this appears to refer to the 2nd earthquake that struck Al-Aqsa after the Holy Desert Quake in 749 CE. This passage is almost identical to what al-Maqdisi wrote in "Description of Syria including Palestine" except that in "The Best Divisions in the Knowledge of the Regions", al-Maqdisi refers to one earthquake while in "Description of Syria including Palestine", he refers to earthquakes (plural).
Ibn al-Athir	Arabic	Biography	Sunni Muslim	~ 1200 - 1231 CE	Mosul	According to Taher (1996), Ibn al-Athir reports earthquakes in al-Massîsa (Mopsuestia) in A.H. 140 (25 May 757 - 13 May 758 CE). According to Ibn al-Athir, the surrounding wall was weakened. Reconstruction of the wall and construction of a large mosque was ordered by Caliph al-Mansûr.
Ibn al-Adim (aka Kemal ad-Din)	Arabic	Biography	Muslim	before 1260 CE	Aleppo or Cairo	Ibn al-Adim (aka Kemal ad-Din) wrote that Masisah (Mopsuestia) suffered from the earthquake of the year A.H. 140 (25 May 757 - 13 May 758 CE).
Earthquake in Mopsuestia in A.H. 139 according to an unknown Muslim source	Arabic		Muslim			Le Strange (1905:130-131), without citing a source, wrote that Massisah (Mopsuestia) had been partially destroyed by earthquake in [A.H.] 139 (5 June 756 to 24 May 757 CE).
Jamal ad Din Ahmad	Arabic	Biography	Muslim	1351 CE	Jerusalem ?	Jamal ad Din Ahmad wrote that the western and eastern parts of Al Aqsa mosque were damaged during the earthquake of A.H. 130. Caliph Al-Mansur (r. 754-775 CE ordered repairs made. The repairs were financed by stripping plates of silver and gold which had covered the Mosque's doors. A subsequent earthquake caused the repaired mosque to fall to the ground. The mosque was still in ruins when Caliph Al-Mahdi (r. 775-785 CE) ordered a rebuild but to different dimensions.
Mujir al-Din	Arabic	Biography	Hanbali Sunni Muslim	ca. 1495 CE	Jerusalem	Mujir al-Din described an earthquake which damaged Al Aqsa Mosque in A.H. 130 (11 Sept. 747 - 30 Aug. 748 CE) which led to a repair during the reign of Caliph Al-Mansur (ruled 754-775 CE). A second undated earthquake is described as destroying the repaired Mosque leading to a second reconstruction to different dimensions during the reign of Caliph Al-Mahdi (ruled 775-785 CE).
Text (with hotlink)	Original Language	Biographical Info	Religion	Date of Composition	Location Composed	Notes

Chronicle of Zuqnin by Pseudo-Dionysius of Tell-Mahre

Background and Biography

Excerpts

English from Harrak (1999)

Part 4
from Harrak (1999:197)
Map showing the location of the Khabur River

Syria 2004 CIA map

Wikipedia - קרלוס הגדול - CC BY-SA 3.0

755-756 The year one thousand and sixty-seven: In the month of Adar (March), on the third day — a Tuesday — a powerful, terrible and dreadful earthquake took place in the middle of the night in the land of the Jazira. Three villages on the Khabur collapsed, and many people perished inside them, like grapes in a wine press. Many other places were also destroyed by this earthquake, brought on by the great number of our sins:

The earth shall totter exceedingly,
the earth shall shake violently,
and it shall sway like a hut.²

This is what our sins are able to do: to shake the ground beneath us!

Footnotes

2 Isaiah 24:19-20

Syriac - embedded

not bookmarked
from archive.org

Chronology

Year	Reference	Corrections	Notes
middle of the night 2 or 3 March 756 CE	The year one thousand and sixty-seven: In the month of Adar (March), on the third day — a Tuesday ... in the middle of the night i.e., Tuesday 3 Adar (March) A.G. 1067	none	calculated for Macedonian reckoning using CHRONOS Adar corresponds exactly to March 3 Adar (March) 756 CE fell on a Wednesday (calculated using CHRONOS) If Babylonian reckoning is used, the date comes out to 3 March 757 CE which fell on a Thursday (calculated using CHRONOS)

Seismic Effects

Three villages on the Khabur collapsed, and many people perished inside them, like grapes in a wine press.

Syria 2004 CIA map

Wikipedia - קרלוס הגדול - CC BY-SA 3.0
Many other places were also destroyed by this earthquake

Locations

on the Khabur
Many other places

Sources

Background Information

Pseudo-Dionysius of Tell-Mahre vs. Dionysius of Tell-Mahre

Online Versions and Further Reading

References

Notes

Date and Day of the Week

Pseudo-Dionysius states that the earthquake struck on a Tuesday in the middle of the night on the 3rd of Adar in what appears to be 756 CE. When one makes Julian day calculations to arrive at the day of the week, 3 Adar (March) 756 CE falls on a Wednesday. This calculation is valid for Universal Time - i.e. the time in Greenwich, England - the same time zone as London. Northern Syria and Mesopotamia are 2 or 3 hours ahead of London depending on location (longitude). Below is a table of days of the week in Universal Time for 3 March (Pseudo-Dionysius) and 9 March (Theophanes) in 756 and 757 CE. Days began at sundown in the Syriac version of the A.G. calendar used by Pseudo-Dionysius (Sebastian Brock, personal communication 2022).

Date	Day of the Week
3 March 756 CE	Wednesday
3 March 757 CE	Thursday
9 March 756 CE	Tuesday
9 March 757 CE	Wednesday

Apparently, by the 4th Century CE, the days of the week were shared across all groups in the Roman empire despite their using different calendars. This habit apparently continued long after the Western Roman Empire fell at the end of the 5th century CE. The fourmilab converter was used to construct the table.

Pseudo-Dionysius of Tell-Mahre, Theophanes, and the Comet of 760 CE

Pseudo-Dionysius of Tell-Mahre drew a picture of a comet in 760 CE which suggests that Harrak (1999) is correct that Pseudo-Dionysius of Tell-Mahre is a contemporaneous source. This also assists in deciphering the chronology of the By No Means Mild Quake. In Pseudo-Dionysius' entry for A.G. 1071, we can read in Harrak (1999:198)'s translation:

759-760 The year one thousand and seventy-one: In the month of Adar (March), a shining sign was seen in the sky¹ before dawn on the northeast side which is called Ram in the Zodiac, to the north of the three most shining stars. Its shape resembled a broom. On the twenty-second day of the month, it was still in the Ram at its head, in the first degree (of the Zodiac circle), the second after the wandering stars Kronos and Ares,² somehow slightly to the south. The sign remained for fifteen nights, to the eve of the Pentecost feast. At one of its ends, which was narrow and more shining^*³ a star was seen and was turning toward the North. The other side, which was large and darker, was turning toward the South. The sign was moving little by little toward the Northeast. This was its form (Vat.sir.162 137r-136v):

Left - original drawing of a comet in 760 CE by Pseudo-Dionysius of Tell-Mahre (Vat.sir.162 137r-136v)

Right - redrawn comet by Harrak (1999:198)

On the eve of the third day after Pentecost^*, the sign was seen again in the evening in the Northwest, and it remained for twenty five evenings. It moved little by little to the South and then it disappeared. Then it reappeared in the southwest, where it remained in this way for many days.

During this time, many schisms took place in the church because of leadership. The eastern monasteries made John Patriarch, while neither the cities of the Jazira nor all the monasteries approved him. The people of the West and Mosul approved George. Because of this the entire Church became troubled.⁴

Footnotes

1 A brief mention in Theophanes 431: A.M. 6252 (760-761).

2 Following Ptolemy, the ancients believed that there were seven "wandering stars", Syriac | | (i.e. planets): The Moon, Mercury, Venus, the Sun, Mars (=Ares), Jupiter and Saturn (= Kronos), all revolving around the earth.

3 | | : See Manna, Dalil, 54, for its meaning.

4 See above pp. 193ff and 216ff.

Hayakawa et al (2017:11-12) suggests that this was a description of Halley's comet.

This should be the record of Halley’s Comet, which has an orbital period of about 75 years. According to Yeomans and Kiang (1981), Halley’s Comet was at perihelion on day 20.671 (UT) of May 760 CE. The comet was also observed by Chinese astronomers. There is a record in JiùTángshū (旧唐书), one of the official histories of the Táng Dynasty, stating that the comet was first observed on May 16, 760 CE within Aries and continued to be visible for about 50 days (JiùTángshū (旧唐书), Astronomy II: p. 1324). The observed period and the association with Aries are consistent between the Chinese and the Syriac records.

The discrepancy in months was discussed by Hayakawa et al (2017:11)

Firstly, we discuss its date and time. According to the text, the event was in the month ādār (March), so it should be March of 760 CE. The event was first seen on the 22nd of the month, remained 15 nights until the dawn of the Pentecost feast, appeared again on the third day after Pentecost, and remained another 25 days. From the text, it is also clear that the event was seen during the night. The time and the duration of the event as well as its shape, which we discuss below, are consistent with the interpretation that it was a large comet. The date of the event, on the other hand, is rather confusing. It is written that this event was seen on March 22 and lasted 15 nights up to the eve of Pentecost, but the date of the Pentecost of that year is May 25 (Grumel, 1958), so it cannot be 15 nights after March 22. A probable explanation for this inconsistency is a miswriting of May
ܐܝܪ(eyar)
as March
‫ܐܕܪ(adar)
in the manuscript as there only one letter difference between them in the Syriac letter system. After a short break, this event reappeared on the eve of the third day after Pentecost and lasted another 25 nights. Thus, we conclude that this event started around 22 May 760 CE and lasted until early July of 760 CE.

If we accept that Pseudo-Dionysius dates this to May, the Macedonian reckoning gives the correct year consistent with what Sebastian Brock (personal communication - 2021) relates - that Macedonian reckoning with a New Year starting on 1 October would be the standard for Syriac sources of the time.

Year	Reference	Corrections	Notes
760 CE	A.G. 1071	none	Macedonian Reckoning dates A.G. 1071 to 1 October 759 - 30 September 760 CE
761 CE	A.G. 1071	none	Babylonian Reckoning dates A.G. 1071 to 2 April 760 - 1 April 761 CE

Pseudo-Dionysius dates the By No Means Mild Quake to 3 Adar A.G. 1067 which is 4 years earlier than A.G. 1071 (760 CE). This dates the earthquake to the 3rd of Adar in 756 CE - according to Pseudo-Dionysius. Theophanes also mentions the comet in his A.M._a 6252 entry which is also 4 years after his earthquake account in A.M._a 6248. In Mango and Scott (1997:596-597)'s translation (Turtledove's translation is available here), we can read Theophanes' description of the comet

[A.M. 6252, AD 759/60]

Constantine, 20th year

Abdelas, 6th year

Paul, 6th year

Constantine, 7th year

...
II In the same year a very bright comet appeared for ten days in the east and another twenty-one days in the west. II

Theophanes' regnal years and his A.M._a dates are all consistently 4 years apart from the comet of 760 CE. Thus, it would appear that Halley's comet of 760 CE also fixes Theophanes earthquake date to 756 CE. By extension, this also indicates that Theophanes' date for the Talking Mule Quake (one of the Sabbatical Year Quakes) in A.M._a 6241 places that earthquake in 749 CE.

Online Versions and Further Reading

References

Cook, D. (1999). "A Survey of Muslim Material on Comets and Meteors." Journal for the History of Astronomy 30(2): 131-160. - open access

Hayakawa, H., et al. (2016). "The earliest drawings of datable auroras and a two-tail comet from the Syriac Chronicle of Zuqnin." Publications of the Astronomical Society of Japan 69. - open access

Neuhäuser, D. L., et al. (2021). "Orbit determination just from historical observations? Test case: The comet of AD 760 is identified as 1P/Halley." Icarus 364: 114278. - open access

Notes

Easter and Pentecost in 760 CE

Grumel (1958:310) lists the Easter date as Sunday 6 April in 760 CE. Since the Pentecost is exactly 7 weeks after Easter, this would indicate that the Pentecost was on Sunday 25 May in 760 CE.

Julian Calendar in 760 CE

Neuhauser et al (2021:7) report that the text of Pseudo-Dionysius reports that "the white sign" (i.e. the comet) was seen for "15 nights until dawn of the feast of Pentecost". Pentecost takes place on a Sunday and in AG 1071, most Christian churches (including churches under the Byzantine Patriarchate) celebrated Pentecost on 760 May 25, but some eastern churches celebrated Pentecost one week later on June 1 (Neuhauser et al, 2021:7). This, according to Neuhauser et al (2021:7), is further evidence that Iyyar (May) was the correct month for the comet not Adar (March).

Neuhauser et al (2021:7) further noted that:

The reason for the two different Pentecost (and Easter) dates in AD 760 is the difference between two ecclesiastical Easter calendars: in AD 760, the first computed (cyclic) full moon after the start of spring (defined for March 21 at the AD 325 Council of Nicaea) was on Saturday Apr 5 according to the 532-year cycle constructed by Irion in AD 562 for the Byzantine Patriarchate (based on a previous 200-year cycle by Andreas of Byzantium for AD 353-552), so that the Byzantines celebrated Easter on Apr 6 (like also the Roman church following the 532-year Easter calendar by Dionysius Exiguus starting in AD 532), while the Armenian, Jacobite, and Nestorian churches followed a different 532-year Easter table, namely the Armenian scholar Anania Siralcaci's (AD 610-685) reform (early AD 660ies) of Andreas' Easter table, according to which the paschal full moon in AD 760 would be on Sunday Apr 6, so that Easter has to be dated Apr 13 (see Sanjian, 1966, Mosshammer, 2008, pp. 257-277). This dispute is also reflected in the Chronicle of Zuqnin (Harrak, 1999):
The year (SE) 1070: Lent was confused. Some of the Easterners introduced Lent on the 18th of: Sebat (Feb) and ended it on the 6th of Islisdn (Apr). Others introduced Lent on the 25th of Sebat (Feb) and ended it on the 13th of Nisan (Apr). All of the Christians were confused, when in one place they celebrated Easter, in another place Palm Sunday; in one place it was Passion week, in another place Easter.
(With the above expression "some of the Easterners" for the other churches, our author probably refereed to the Byzantine Patriarchate or other churches west of the Euphrates.)

Our Chronicle reported the Easter dating problem for SE 1070, i.e. AD 758/9; in AD 759, Easter Sunday was on April 22, in AD 760 on April 6 or 13 (see above); hence, the above given end date of lent (Apr 6 or 13) points to AD 760; the given introduction of lent on Feb 18 or 25 would be a Monday in 760, i.e. the correct weekday for the start of lent in the Syriac churches (where there is no Ash Wednesday). There is also a brief mention of this problem by Theophanes, who dates it to AD 760. Hence, all the evidence points to AD 760 for the report on the Easter dating problem misdated to AD 759 in the Chronicle of Zuqnin. The same problem also happened in AD 570 and 665 (Mosshammer, 2008, pp. 276-277).¹⁴

The monastery of Zuqnin belonged to the Syriac Orthodox church, informally known as the Jacobite Church; this is known, because our chronicler listed bishops and patriarchs, which were also listed by the 12th century Michael the Syrian (e.g. Chabot, 1899-1910), who clearly identified them as to belong to the Syriac Orthodox patriarchate (Jacobite). Hence, it is clear that Easter was on Apr 13 and Pentecost on June 1 at the monastery of Zuqnin: since it is reported that the comet was seen "for fifteen nights, until dawn of the feast of Pentecost", it was first detected on May 18 "before early twilight". This is well consistent with the fact that the Chinese sources give May 17 for the first detection (Section 3.1).

Footnotes

14 The Chronicle of Zuqnin does not report any Easter dating problems for AD 570 nor 665; this problem, called "crazatik" or "Erroneous Easter", was resolved only in AD 1824 (Mosshammer, 2008, p. 277). Our Chronicle narrates one other Easter confusion for SE 857 (i.e. Easter AD 546, but correct year is AD 547, see Mosshammer, 200E, p. 256), when three different dates for lent and Easter are mentioned to have been followed by different parts of the population. For a discussion of the Easter problem and Easter tables, see McCluskey (1998, pp. 84-87) and for the Eastern churches also Sanjian (1966) and Mosshammer (2008).

Description of the Comet as a "white sign" or "broom"

The comet described by Pseudo-Dionysius of Tell-Mahre is not explicitly described as a comet in the text. Rather, it is referred to variously as "the white sign" or "broom". Neuhauser et al (2021:7-8) provided the following for why they viewed as a description of a comet:

2.4. The "white sign" as comet Criteria

In transmitted texts on celestial transients, using a pheno-typical description, it is often uncertain which kind of celestial phenomenon is meant: in our text the phenomenon is not called "comet", and even if it would be called that way, it may still be uncertain whether a comet in today's sense is meant. Five criteria are developed (timing, position/di-rection, colour/form, motion/dynamics, and duration/repetition) for various kinds of celestial phenomena, see, e.g., Neuhauser and Neuhauser (2015a) and D.L. Neuhauser et al. (2018a) for criteria for aurora borealis and D.L. Neuhauser et al. (2018b) for meteor showers (and aurorae).

The "white sign" or "broom" reported in the Chronicle of Zurinin fulfils all five criteria for comets:

timing, observed at night-time or twilight: "before early twilight", "fifteen nights", "at evening time", "twenty-five evenings", and stars and planets are mentioned (and shown in the drawing)

Position of first and/or last sighting: often close to Sun, in or near the ecliptic: "before early twilight, in the north-east" "seen again at evening time, from the north-west", and "in the Zodiac [sign] which is called Aries (emro)"; also tail direction away from the Sun: "[at] its one end/tip, the narrow one, a very bright star (kawkbo) was seen at its head/end/tip. And it was tilting to the north side, but the other wide and very dark one was tilting to the south side"

colour and form (extension): "white sign", "resembled in its shape a broom", the white broom points to the comet dust tail appearing white due to reflection of sunlight (while the plasma tail would appear bluish and much fainter)

dynamics, i.e. moving on sky relative to the stars: first "north from these three stars", "it was going bit by bit to the North-East", seen until Pentecost (June 1 morning), then again soon later after conjunction with the Sun, "it was seen again from the north-west", "it was going bit by bit to the south", etc.

duration: "remained for fifteen nights", "remained for twenty-five evenings", etc.

Furthermore, our Chronicler connects the sighting of this transient object as negative portent with unfortunate events (e.g. "many schisms"), as was not unusual at this time.

Celestial nomenclature in the Chronicle of Zuqnin

Halley's Comet (Wikipedia)

Wikipedia

Article by Neuhauser et al (2021) on the Comet of 760 CE

Introduction and Summary

Neuhauser et al (2021) identified Halley's Comet (1P/Halley) as a comet described by Pseudo-Dionysius of Tell-Mahre (Chronicle of Zuqnin), Theophanes, Agapius of Menbj, Nu'aym ibn Ḥammmad, Michael the Syrian, and Chinese, Japanese and Korean sources. They performed astronomical calculations (least squares fitting of Keplerian orbital solutions) to fit "date corrected" historical reports paying close attention to the position and locations of celestial objects described in the sky by Pseudo-Dionysius of Tell-Mahre and Chinese sources. Despite chronological inconsistencies (month and year) among the sources (possibly due to scribal errors) which they had to "correct", they identified the comet as 1P/Halley and obtained a precise perihelion time (760 May 19.1 ± 1.7) and an inferior conjunction between the comet and Sun (June 1.8) which is about one day different from a previously published orbit (760 May 31.9, Yeomans and Kiang, 1981). Based on their orbital model, philological arguments, and the way the drawing is embedded in the text, Neuhauser et al (2021:7) suggest that Pseudo-Dionysius drew the comet, 3 stars (Ari aka Aries), and two planets (Mars and Saturn) from an observation made in the early morning (~3 am ?) on 25 May 760 CE. Their reconstruction of the night sky when and where they suggest the comet was drawn is shown below (Fig. 2) along with a reproduction of the drawing and text by Pseudo-Dionysius (Fig. 1).

Fig. 2 - A comparison with Fig. 1 shows that the original drawing is for a date around 760 May 25 in the early morning (2:40 h local time, 0 h UT): both Sun (NE) and Moon were under the horizon at that time, 1P/Halley was ~7° above the NE horizon. IAU constellations are indicated in black, the ecliptic in orange with dots at the borders of zodiacal signs. The planets Mars (0.7 mag, red dot) and Saturn (0.5 mag, yellow dot) are still close to each other. The position of the comet is indicated on our own new (green) orbit (and as grey cross on the old orbit, JPL, YK81); both orbits start on May 17. The drawing (Fig. 1) was not used for orbital reconstruction. Here and in all other figures, the comet plasma tail pointing away from the Sun is displayed, while observation and drawing regard the dust tail. This and all other such figures are drawn with Cartes du Ciel (v3.10).

Fig. 1 - Syriac text and drawing: The relevant Syriac text from the Chronicle of Zuqnın (finished AD 775/6) on the comet AD 760 (1P/Halley) – from the middle of the first line shown to the middle of the last line – with a drawing embedded in the text (Vatican Library, Vat. Syr. 162, folio 136v): the comet to the left, the three brightest stars of Aries (α, β, and γ Aries) in the center, and the planets Mars and Saturn as Ares and Kronos to the right, as identified in the Syriac caption. The drawing fits best for around May 25 given the relative position of Ares/Mars east (left) of Kronos/Saturn, both west of Aries. See Fig. 2 for a comparison with a computed position of 1P/Halley for May 25 at 0 h UT.

Background and Biography

Background and Biography - Pseudo Dionysius of Tell-Mahre author of the Chronicle of Zuqnin

Background and Biography - Theophanes

Background and Biography - Nu'aym ibn Ḥammmad

Background and Biography - Agapius of Menbij

Background and Biography - Michael the Syrian

Excerpts

Literal English Translation of the Chronicle of Zuqnin from Neuhauser et al (2018)

brackets [] and line breaks are from Neuhauser et al (2021:6).

The year [SE] one thousand seventy one (AD 759/760).
In the month of iyyōr (May)⁵ a white sign was seen in the sky,
before early twilight (Syriac: šafrō), in the north-east [quarter],
in the Zodiac [sign] which is called Aries (emrō), to the north from these three stars (kawkbē) in it, which are very shining.
And it resembled in its shape a broom, while it was still in the same Aries (emrō) at its edge/end/furthest part (rīšeh)⁶:
in/at the initial degree (mūrō)⁷ [of] the second⁸ [sign] (i.e. Taurus) from these wandering stars (kawkbē), Kronos (Saturn) and Ares (Mars), like somehow a bit to the south, on [day] 22 in the same month.
And the sign itself remained for fifteen nights, until dawn (nōgah)⁹ of the feast of Pentecost.
And [at] its one end/tip (rīšōh), the narrow one, a very bright star (kawkbō) was seen at its head/end/tip (rīšeh).¹⁰ And it was tilting to the north side, but the other wide and very dark one was tilting to the south side,
and it was going bit by bit to the North-East [direction].
Its shape is as follows [now 4 points forming a rhomb meant as pointing to the drawing, which is embedded in the next lines, Fig. 1].
However, at the beginning (nōgah)¹¹ of [the] third [day] after Pentecost, it was seen again at evening time, from the north-west [quarter].
and it remained for twenty-five evenings.
And it was going bit by bit to the south:: [actually 4 points forming a rhomb meant here as a break].
And it again disappeared.
And then it returned [and] was seen in the south-west¹² [quarter],
and thus there it remained for many days.

Footnotes

5 Chabot (1895), Harrak (1999), and Hayakawa et al (2017) read "adar/odor” and gave “March” here (“odor” is the correct West-Syrian transliteration here, while “adar” is East-Syrian); in Syriac, the words for March (odor) and May (iyyor) are written very similar: ‘DR and ‘YR, respectively. We came to the conclusion that iyyor is given here in the MS:

epigraphically, the Syriac letter /d/ (as in odor) should have a tail, which is not found in the MS

there is no space between /y/ and the following /r/, the two letters are ligatured, but if it were /d/ (as in odor) there should be a space (as seen in all occurrences of this letter in the month name ‘DR = odor)

because of a dot underneath the /y/, the letter was thought to be /d/, i.e. reading ‘DR = odor, however, in five occurrences of the month name ‘YR in the MS, four do not have this diacritical dot, one (folio 150v) has it as a thick one, which should be thin – the chronicler was by no means consistent in using diacritics and symbols. Michael the Syrian also gives iyyor as month of the first sighting (Section 4d).

6 The Syriac word rıseh mainly means “its head”, but “its tip, its edge, its end, its furthest part” etc. and such meanings are also attested in dictionaries (e.g. Sokoloff, 2002). See below for a discussion of position 2.

7 The Syriac muro from Greek moira for degree is also attested in Ptolemy’s Almagest for degree.

8 Harrak (1999) gave “in the first degree (of the Zodiacal circle), the second”; Hayakawa et al.: “in the first degree (of the sign), two (degrees)”; see below for a discussion of position 2.

9 Chabot: “la veille”; respectively “eve” in Harrak (1999); the comet was seen in the morning, as mentioned before; for nogah, see footnote 11.

10 An alternative translation could be “and its one end/tip, the narrow one, was very bright; a star was seen at its head/end/tip”, but it does not work because in the MS there is a punctuation between qaṭıno (“narrow”) and yatır bahuro (“very bright”). Hayakawa et al. (2017) brings a punctuation in their transliteration that is in many places inconsistent with the autograph, in particular they overlooked the punctuation by translating “And one end of it was narrow and duskier, one star was seen in its tip”, and they confused the meaning by rendering “duskier” instead of “very bright”: the original word bahuro means “dim” in old Syriac, but later also “bright” after Arabic influence; Chabot (1933) emended bahuro into nohuro, which just means “bright”, but this emendation is not necessary; the first letters (/b/ and /n/) are also quite different in Syriac. The translation by Hayakawa et al. (2017) is not satisfactory: “duskier” would be in contrast to the “star” at this end (comet head), and it would not be in contrast to what is later given as “wide and very dark” (the other end); the drawing also clearly shows a “very bright star”, the comet head; see below for our discussion of the drawing.

11 For the Syriac nogah, instead of “beginning”, Hayakawa et al. (2017) gave “dusk”, which is not attested in Syriac dictionaries; the word nogah does mainly mean “dawn” (see above), but this is not possible here, because the observation was in the “evening time”. Harrak (1999) gave “eve”. Our translation “at the beginning” follows oriental calendars, where the 24 h-day begins with sunset, e. g. nogah d-shapto meaning “Sabbath vespers”, which happen in the evening after sunset. In the report on a bolide in AD 754, the Chronicle of Zuqnın gave the timing as “on Tuesday, when Wednesday was dawning (nogah) ... In the same evening ...”, i.e. it uses nogah here for the beginning of the oriental 24 h-day (D.L. Neuhauser et al., 2018b, event 5, p. 77, Harrak, 1999, p. 196).

12 Lit. west southern

English Translation of the Chronicle of Zuqnin from Harrak (1999)

Part 4
from Harrak (1999:198)

759-760 The year one thousand and seventy-one: In the month of Adar (March), a shining sign was seen in the sky¹ before dawn on the northeast side which is called Ram in the Zodiac, to the north of the three most shining stars. Its shape resembled a broom. On the twenty-second day of the month, it was still in the Ram at its head, in the first degree (of the Zodiac circle), the second after the wandering stars Kronos and Ares,² somehow slightly to the south. The sign remained for fifteen nights, to the eve of the Pentecost feast. At one of its ends, which was narrow and more shining^*³ a star was seen and was turning toward the North. The other side, which was large and darker, was turning toward the South. The sign was moving little by little toward the Northeast. This was its form (Vat.sir.162 137r-136v):

On the eve of the third day after Pentecost^*, the sign was seen again in the evening in the Northwest, and it remained for twenty five evenings. It moved little by little to the South and then it disappeared. Then it reappeared in the southwest, where it remained in this way for many days.

During this time, many schisms took place in the church because of leadership. The eastern monasteries made John Patriarch, while neither the cities of the Jazira nor all the monasteries approved him. The people of the West and Mosul approved George. Because of this the entire Church became troubled.⁴

Footnotes

1 A brief mention in Theophanes 431: A.M. 6252 (760-761).

2 Following Ptolemy, the ancients believed that there were seven "wandering stars", Syriac | | (i.e. planets): The Moon, Mercury, Venus, the Sun, Mars (=Ares), Jupiter and Saturn (= Kronos), all revolving around the earth.

3 | | : See Manna, Dalil, 54, for its meaning.

4 See above pp. 193ff and 216ff.

The comet is referred to later in the text (as 'the broom').

Part 4
from Harrak (1999:200-201)
Brackets from JW

The year one thousand and seventy-five [A.G. 1075 = 1 Oct. 763 to 30 Sept. 764 CE]: A severe plague among horses took place in the whole land. ... This disease spread throughout all the nations and kingdoms of the earth, to the point that people were left without horses. The effect of ’the broom’ seen a short while before, was clearly seen in reality, as it swept the world like a broom that cleans the house.

Transliteration of the Chronicle of Zuqnin from Neuhauser et al (2021)

Part 4
from Neuhauser et al (2021:Fig. 15)
Transliteration of the Syriac text on the comet of AD 760 (see also Fig. 1 and Section 2).

English Translation of Theophanes from Mango and Scott (1997)

from Mango and Scott (1997:596-597)

[am 6252, AD 759/60]

Constantine, 20th year
Abdelas, 6th year
Paul, 6th year
Constantine, 7th year

... In the same year a very bright comet appeared for ten days in the east and another twenty-one days in the west.^b

Footnotes

b Cf. Ps.-Dion. Chron. 63-4, AG 1071.

English Translation of Theophanes from Turtledove (1982)

from Turtledove (1982:120)

ANNUS MUNDI 6252 (SEPTEMBER 1, 760— AUGUST 31, 761)

... In the same year a brilliant apparition appeared in the east for ten days, and again in the west for twenty-one.

English Translation of Theophanes from Mango and Scott (1997) - embedded

see [A.M. 6252, AD 759/60] on page 596
from Mango and Scott (1997:596-597)
from archive.org

English Translation of Theophanes from Turtledove (1982) - embedded

see ANNUS MUNDI 6252 starting on page 120
from Turtledove (1982:120)
from archive.org

English Translation of Nu'aym ibn Ḥammmad from Neuhauser et al (2018)

brackets [] are from Neuhauser et al (2021:17).
The same quote (minus the last sentence) appears in Cook (1999:136)

“We saw the comet rising in Muḥarram in the year [Anno Hijra, AH 145 = AD 762/3] with the dawn from the east, and we would see it during the dawn for the rest of Muḥarram; then it disappeared. Then we would see it after the sunset in the twilight, and afterwards between the north and the west for two month or three. Then it disappeared for two or three years.³⁸

Footnotes

38 This report by Nu'aym ibn Ḥammmad then continues with:

Then we saw a mysterious star with blazing fire the length of two degrees, according to what the eye saw, near Capricorn, orbiting around it like the orbit of a planet during the months of Jumada [July] and [some of the] days of Rajab [Oct] and then it disappeared.

(as translated by Cook, 1999 with his additions in brackets, dated by him to AH 145 = AD 762/3)

This and the following reports definitely do not belong to the comet in AD 760.

English Translation of Agapius of Menbij from Neuhauser et al (2018)

brackets [] are from Neuhauser et al (2021:17).

In this year [ AD 760] the star with a tail appeared, and it was in Aries before the Sun, and the Sun was in Taurus. It proceeded until it was under the rays of the Sun, then went behind it and stayed 40 days. (Cook, 1999; Vassiliev, 1911)

English Translation of Agapius of Menbij from Vasilev (1909) and Cook (1999)

from Vasilev (1909)

In this same year, a comet [appeared]. It was in Aries, in front of the sun, when the sun was in Taurus. It went on until it came beneath the rays of the sun; then it went behind and remained for forty days.

from Cook (1999:136)

In this year the star with a tail appeared, and it was in Aries before the sun, and the sun was in Leo. It proceeded until it was under the rays of the sun, then went behind it and stayed 40 days²³.

Footnotes

(23) I can't find the footnotes in this article.

Cook (1999:136) notes that this observation is probably from Theophilus of Edessa himself. Neuhauser et al (2021:17) wrote the following about the Sun being in Leo:

Note that Cook (1999) incorrectly gave “and the Sun was in Leo”, while the text clearly gives Taurus, see Vassiliev, 1911.

English Translation of Agapius of Menbij from Vasilev (1909) - embedded

see text starting with In this same year, a comet
Vasilev (1909)
from tertullian.org

English Translation of Michael the Syrian from Neuhauser et al (2021)

brackets [] are from Neuhauser et al (2021:19).

And in this year in the month of iyyor (May), a comet star [kawkbo qumiṭus – the latter obviously from the Greek kometes] was seen before the Sun in Lamb (Aries), when the Sun was in Taurus. It looked like a pillar/column [‘omudo] and was extending its rod⁴⁰ to the south. It moved close to the Sun for twenty days, and became below the rays of the Sun for three days. Thereafter, it was behind the Sun for forty days. Due to its appearance, fear gripped everyone

Footnotes

40 What is translated as “rod” points to the tail. Chabot translated it as “chevelure”, i.e. “lock of hair” (Chabot, p. 524 n.3). The 16th century Edessan manuscript emended the term sabuqo (“rod”) to sobqo (“emission”), and Chabot interpreted this word as (curled) hair.

English Translation of Chinese Texts from Neuhauser et al (2021)

Understanding historical observations from China - Neuhauser et al (2021:5-6)

In imperial China, court astronomers observed the sky all day and night in order to notice changes²; owing to this practise — among other transients — comets were recorded in observing logs. While the original night reports for the 8th century are not extant, later compilations or copies thereof are available, which are shortened and may suffer from scribal errors. These include: Jiu Tang shu (JTS) by Liu Xu et al. (945) from AD 945, Tang hui yao (THY) by Wang Pu et al. (961) from AD 961, and Xin Tang shu (XTS) by Ouyang Xiu et al. (1061) et al. from AD 1061, i.e. the astronomical chapters of the History of the Tang dynasty (Tang shu), as well as the collection Wenxian tongkao (WHTK) by Ma Duanlin from AD 1317. Extracts for comets were published by Pingre (1783) in French as well as by Hsi (1957, only for 1P/Halley AD 837), Ho (1962, see also Hasegawa, 1980 for comments and additions), Kiang (1972), Xu et al. (2000), and Pankenier et al. (2008), all in English.

For general information about astronomy in imperial China, please refer to the detailed monographs by Needham and Wang (1959) and Sun & Kistemalcer (1997, henceforth SK97), and short summaries also in Kiang (1972), Clark and Stephenson (1977), Stephenson (1994), Xu et al. (2000), Stephenson and Green (2002), and Pankenier et al. (2008).

Since the Han dynasty (206 BC to AD 220), the sky was structured into about 283 asterisms of various sizes with almost 1500 stars in total (down to 6th mag and a few fainter ones, these are of course incomplete); a Chinese asterism³ can contain one, few or many stars; the stars of an asterism were combined by lines (skeletons). While this system had a strong continuity since the Han, some details changed later (not only in Korea and Japan, also in China).

The term zing, often rendered as star(s), can be combined to, e.g. ke zing as guest star(s) or hui zing as broom star(s). Classical Chinese word morphology does not distinguish between singular and plural.

The names of 28 asterisms are also used for the 28 lunar mansions (LM), which are right ascension ranges from the determinative (or leading) star of one LM to the next, omitting the south polar region which was not visible from the Chinese mainland, while the north circumpolar region was of special importance known as the enclosure (yuan) named Ziwei' or Zigong', see Stephenson (1994), SK97, and Ho (2003, p. 144). For a list of the 28 LMs and their determinative stars, see, e.g., SK97, Xu et al. (2000), Stephenson and Green (2002), or Pankenier et al. (2008). Given this equatorial system, hour angles of objects can be given as a certain number of du (0.9856°) East of the respective determinative star.

There also exist Chinese star charts from the time of the Tang dynasty, namely the Dunhuang maps (manuscript Stein 3326 dated AD 649-684 by style of characters, mentioning of an astronomer of that time, style of clothing shown in a figure, and usage of two taboo characters), where more than 1300 stars in 257 asterisms are drawn with skeleton lines, apparently in azimuthal projection (Bonnet-Bidaud et al., 2009).⁴

Separations on sky including comet tail lengths are given in certain old Chinese linear measures, which can be converted to angles such as 1 chi being about 1° (Stephenson and Green, 2002; Kiang, 1972 gave 1 chi = 1.50 ± 0.24°), 1 can being 0.1 chi, and 1 zhang =10 chi (see Ho, 1966; Kiang, 1972; Wilkinson, 2000; Stephenson and Green, 2002).

Sometimes, in addition to or instead of a celestial position given as one coordinate, angle, or separation, the compilations of observing records list the general direction as azimuth, which can be specified in terms of several different compasses; the precision of the compass used (e.g. 4- or 24-point) then defines the uncertainty or azimuth range of such a position.

The observing dates are specified by name of the emperor, year with a multi-year reign period, lunar month, and then usually the day count in a 60-day-cycle (ganzhi) - a continuous counting was achieved prior to the advent of the imperial period in 221 BC; sometimes, instead of or in addition to the day count (1-60), the age of the Moon is given; the luni-solar calendar had 12 lunar months starting on the second new-moon after winter solstice (i.e. in January or February), plus seven intercalary months in 19 years (called just "x-th intercalary month" located after the "x-th" month), like the Meton cycle; these rules were in use since a calendar reform during the Han.

The normal Chinese 24 h-day ran from midnight to midnight, but in astronomical records, for observations after midnight, the former date is given (some late sources may have modified the date to the new civil date). The night was separated into five watches of equal lengths per night, which changed during the year.

Footnotes

2 Such observations were performed, because it was thought that they identify dangerous political trajectories (astrology, but also weather rules etc., e.g. from the Han dynasty: "320 stars can be named. There are in all 2500 ... All have their influence on fate", Needham and Wang, 1959, p. 265), or can indicate misgovernment ("any anomalous happenings in nature ... were construed as signs of warnings by heaven toward the misbehaviour or misgovernment of the ruler of man", also from the Han, Wang Yiichuan, 1949, Bielenstein, 1984). The dramatic appearance of comet Halley in 12 BC, for example, was interpreted by both Gu Yong and Liu Xiang as a sign that the Western Han dynasty was in danger of collapse; the two writers each identified different court factions as responsible for the peril the dynasty faced, and both held that if the right actions were undertaken the sign would vanish and the dynasty would likely survive; neither writer saw the future as fixed or determined, though both associated it with an elevated likelihood of disastrous political events (Chapman, 2015).

3 Groups of stars (xing cang) were given certain names, which do not normally reflect their appearance on sky, even if connected with skeleton lines; this is similar for Babylonian, Western, and Chinese constellations. To discriminate from Western constellations, Chinese star groups are often called asterism. However, this term derives from the Greek asterismos as was used by Ptolemy in his Almagest for what we now call constellations (now defined as fields on sky by IAU mostly based on Ptolemy's Almagest). Xing qun is the modern Chinese term for constellation; literally, it means group of stars.

4 Stars and asterisms on the 13 charts are drawn only in a crude way with rough positions and several mistakes, e.g. the asterism name Lou in Aries is missing (but the three stars apparently are drawn), the colour-convention for stars is not followed strictly (Chinese charts show the stars and asterisms from three Han dynasty schools in different colour: red for those from Shi Shen, black from Gan De, and white/yellow from Wu Xian), twice the Chinese characters for "right" zuo and "left" you, which are very similar, are mixed up, the asterism Sangong near the pole is shown twice (Bonnet-Bidaud et al., 2009). Given that the maps are drawn on expensive pure mulberry fibres (3940 mm by 244 mm scroll), this atlas may be a copy produced by a wealthy but not well-talented student of Li Chunfeng, one of the main astronomers of the 7th century, who is mentioned in the accompanying text and could have done the (now lost) original map based on observations and/or the astronomical chapters of the Jin shu, which he had written.

The comet of AD 760 as reported in classical Chinese sources - Neuhauser et al (2021:12-14)

We present here our own new, technical, very literal translations, which aim to preserve the detail and word order of the original Chinese, but have been slightly smoothed to present correct English sentences (see appendix for the Chinese texts); significant variants in Ho (1962, no. 273 and 274), Xu et al. (2000), and Pankenier et al. (2008) are mentioned in footnotes. First, we translate the oldest text from JTS (36.1324, and much shorter in 10.258), counted as object no. 273 in Ho (1962), with some Chinese terms, explanations, and significant variants from THY (43.767) and XTS (32.838, unless otherwise specified) in round brackets, our additions in square brackets (e.g. the day/night number in the 60-day-cycle), starting with the night 760 May 16/17, line breaks by us:

Tang Emperor Suzong (literal: Tang[‘s] Solem Ancestor) Qia- nyuan [reign-period]²⁰ 3[rd] year, 4[th] month, dingsi (54) night (THY gives the lunar date: “27[th] day”, XTS omitted “night”), 5[th] watch (“5[th] watch” omitted in THY and XTS),
[a] broom (hui) [star] (XTS: “ hui xing” for “broom star”) emerged (THY: “seen at (yu)”, XTS: “there was ... at (yu)”) east (dong) direction, colour being white, length (JTS 10.258 adds: about) 4 chi (THY and XTS have color and length after the next phrase),
it was located/situated in (zai) Lou, [in] Wei²¹ for-a-while/space (jian),
it rapidly moved toward east (dong) north (bei) corner (THY omitted “corner”; XTS has instead: “east direction rapidly moved”),
passing through Mao, Bi, Zui (XTS: “Zuixi”), Shen,²² Jing (XTS: “Dongjing”), Gui (XTS: “Yugui”), Liu²³ [and] Xuanyuan (THY added “xiu” for “lodge”²⁴),
reaching Taiwei Youzhifa²⁵ 7 cun position (THY: “reaching Taiwei west (xi), Youzhifa west (xi) 7 chi”; XTS omitted “Taiwei” and has only “reaching Youzhifa west (xi)”),
In all more than 50 days, only then (fang) [it] disappeared (THY very similar; XTS has “in all more than 50 days, [it was] not seen”)” (continued below).

We will discuss this transmission in detail below to obtain dated positions.

Next, we present additional relevant texts, not given in Xu et al. (2000) and Pankenier et al. (2008). Ho (1962) cited under his no. 274 a record from JTS 36.1324 (Ho: CTS 36/8a), and gives two more texts, HTS 32/6b (=XTS 32.838) and, almost identical, WHTK 286/23a (286/ 29b-30a in the Siku quanshu huiyao edition). Here our own new literal translation of the JTS text (with variants from XTS and also from THY 43.767), which follows immediately after the previous comet report:

Intercalary 4[th] (XTS omitted “4[th]”) month, xinyou (58=May 20 with night 20/21), new-moon (THY: “ Shangyuan reign-period, [initial] year, intercalary 4[th] month, 21[st] day” (=June 9)), [an] ominous star (yao xing) seen at (yu) south (nan) (THY: “west (xi)”; XTS: “there was [a] broom star (hui xing) at (yu) west (xi)”) direction, length several zhang.
This time, since [the] beginning [of the] 4[th] month, heavy fog [and] heavy rain, reaching [the] end [of the] 4[th] intercalary month (i.e. the last 10 days), only then (fang) [it, i.e. bad weather] stopped (instead of this whole sentence, THY and XTS have “Reaching 5[th] month, [ominous star] disappeared”, XTS adds: “Only [when] reaching ...”).
This month, rebel bandit Shi Siming again captured [the] Eastern Capital (i.e. Luoyang). Grain prices leapt [up] in expense, dou (i.e. about 6 liters of rice) reaching eight hundred wen. People ate each- other [and] corpses covered [the] ground.

After reporting the disappearance of the comet, "Only [when] reaching 5[th] month ...", XTS (32.838) adds:

Lou corresponds to [the pre-imperial state of] Lu, Wei [and] Mao [and] Bi correspond to Zhao, Zuixi [and] Shen correspond to Tang, Dongjing [and] Yugui correspond to [the] capital city (jingshi) (meaning probably the historical capital of the Zhou dynasty) allotment, [as for] Liu, its half corresponds to [the] Zhou allotment. As-for-cases-in-which (zhe) two brooms seen in-succession, amassing disaster. Moreover, Lou, Wei space (firm) [corresponds to] Tiancang (`Celestial Granary').

The whole last paragraph is an astro-omenological interpretation of the comet report. In Chinese astro-omenology, Wei (LM 17) governs granaries and warehouses, as found in the Jin shu ( , p. 100, 2003, p. 147) — and indeed, the term Tiancang means `Celestial Granary/ ies'. There is also an asterism Tiancang, which is however located mostly in LM Kid and only partly in LM Lou; there are further asterisms meaning `Celestial Granaries' in LMs Lou and Wei, e.g. Tianjun (SK97), written Ticatqurt in Pankenier et al. (2008). (Lou governs cattle rearing and animal sacrifices, see Ho, 1966, p. 100.)

In the past, it was considered that there were two comets in spring AD 760, e.g. Yeomans et al. (1986). All sources for Ho no. 274 give "several zhang" as length, so that one could consider that they mean the same object: the "ominous star" (yao xing) in the west in THY (June 9 evening) would fit with the comet path given in the previous text; the object(s) in JTS, XTS, and WHTK for May 20/21 (morning) in the south or west are not consistent with the path of comet no. 273, which was then still in the NE. If the previously cited JTS text refers to the same object, a date correction would be needed — it should be June 9 (as in THY) instead of May 20. One explanation could be: May 20 corresponds to the 58th day, xin-you in the 60-day-cycle, while June 9 is the 18th, xin-si, so that only the 2nd part would have been mistaken in JTS, XTS, and WHTK by a copying scribe (you for si); THY conserves the correct date as date in the lunar calendar (day 21 = June 9), converted from the 60-day-cycle as found in its source. Note that the two dates (May 20 and June 9) pertain to the same Chinese lunar month (4th intercalary month), just the day within the month is different. More reasonably, since "new moon", i.e. the first day of the lunar month, is given in JTS and XTS in addition to xin-you (58), which is correct for May 20, a confusion between date and event might be just due to a false concatenation in the compilation process; furthermore, it is plausible that the second comet report, preserved correctly in the THY text, originates from another source and observing site, where, e.g., weather conditions did not allow a detection earlier than June 9.

To sum up, among the three texts for Ho object no. 274, the THY transmission appears to be the least corrupt: sighting on June 9 (JTS and XTS: May 20/21), THY has west direction (XTS also west, but JTS has south). That the information in THY is most reliable here, relies on the assumption that the "two" objects Ho no. 273 and 274 are one and the same comet; this is supported by the fact that the duration in the first comet report (about 50 days after May 17/18) corresponds well with the disappearance in THY and XTS ("Reaching 5[th] month, [it] dis¬appeared"). This assumption is also supported by the following astro-omenological interpretation in XTS 32.838: "As-for-cases-in-which (zhe) two brooms seen in-succession, amassing disaster". In the translation "two separate broom stars appearing simultaneously" ( phenson and Yau, 1985), the word "separate" is added (but not given in the Chinese text); the sense of the adverb in Classical Chinese (reng) suggests repetition with close or immediate proximity in time ("appear one after the other" or "in quick succession" or "repeatedly").²⁶ That it is only one comet is justified by further independent reports, where the conjunction with the Sun is explicitly reported, e.g. the Chronicle of Zugnin (see above) and several further East Mediterranean and West Asian reports (Section 4).

There is one more extant source, XTS 6.162-3, but the variant transmission gives only very short information:

4[th] month ... dingsi (54), there was [a] broom star, emerged at (yu) Lou, Wei, Jiwei (56), Lai Zhen (died ca. AD 763) became Sharman Eastern Circuit's Military Commissioner charged to overcome [the rebellion of] Zhang Weijin. Intercalary month (4[th] omitted) xinyou (58), there was [a] broom star, emerged at (yu) west (xi) direction.... Jimao (16), [there was a] large amnesty, change [of] reign-period [title], grant [of] civil [and] military office [and] rank.... This month [was a] large famine. Zhang Weijin surrendered.

This late source shows how compilers work: XTS 6.162-3 concatenated input from XTS 32.838, a source which is already shortened — as one consequence, the comet's position at the beginning is a bit corrupt. This source, which belongs to the "Basic Annals" (Benji) section of the history (a general chronicle of events during the reign of each emperor), rather than the technical treatise, is only interested in the first appearance of the comet (first sightings at the very beginning and after conjunction with the Sun) - the main point is the connection to historical events on Earth.

The year 760 fell midway through the An Lushan rebellion (AD 755-763). The early years of the rebellion had witnessed the abdication of an emperor who had reigned for more than forty years, the fall and subsequent recapture of the main capital at Chang'an, and casualties reportedly numbering in the millions. In both JTS and XTS 6.162-3, close chronological proximity associates the comet's appearance with politics, the rebellion and the famine that accompanied it; XTS 32.838 reflects these in an astro-omenological interpretation.

As quoted above, JTS reports the weather: "This time, since [the] beginning [of the] 4[th] month (new-moon on Apr 19/20), heavy fog [and] heavy rain, reaching [the] end [of the] 4[th] intercalary month (i. e. the last 10 days, new-moon on June 17/18), only then [it, i.e. bad weather] stopped." Monsoon typically arrives in May and may well end in June. In addition to shortenings and omissions in the compilation process, problems with weather and the rebellion may also have influenced the observations and the data record (and might be partially responsible for the famine). Still, since the beginning of the Tang dynasty (AD 618), there are no better transmitted records for any comet before AD 760 (see Pankenier et al., 2008 for the texts).

The Korean "Chronicle of the Three Kingdoms" (Samguk sagi) briefly reported a " hui comet" sometime during the lunar month 761 May 9 to June 7 (Ho, 1962, no. 275); this work, compiled AD 1142-1145 (Schultz, 2004), is often off by a few years — probably, our comet is meant. The Kingdom of Silla is traditionally dated 58 BC to AD 935. However, the Silla dynasty, which united the whole of peninsula, ran from AD 668 to 935.

From the Chinese observations also all five comet criteria mentioned above (Section 2) are fulfilled. A "broom colour being white" also points to a comet with dust tail.

Footnotes

20 Xu et al. (2000) added here “i.e. 1st year of the Shangyuan reign period” – in fact the Shangyuan reign period started only at the beginning of the 4th intercalary month, after the Qianyuan reign period had ended with the 4th month.

21 Lou (“Hillok” or “Lasso”) and Wei (“Belly” or “Stomach”, see SK97 and Ho, 1966) could be the asterisms of that name (both in “our” Aries, i.e. the constellation as defined by the International Astronomical Union) or the lunar mansions (right ascension ranges) named after these asterisms (LM 16 and LM 17, respectively) starting in the west with the determinative star β Ari for Lou and with 41 Ari for Wei. See below for position C1.

22 Xu et al. (2000) give “Can” here, which is a more common pronunciation of the Chinese character; however, in this context, the correct pronunciation is “Shen”, LM 21 and an asterism in Orion.

23 This list could point to either asterisms or LMs: Mao (“Mane”, LM 18), Bi (“Hunting net”, LM 19), Zui or Zuixi (“Beak”, LM 20), Shen (“Triaster” or “Hunter”, LM 21), Jing or Dongjing (“Eastern Well”, LM 22), Gui or Yugui (“Spectral Carriage”, LM 23), and Liu (“Willow”, LM 24); translations of asterisms here are the Han time interpretation, some have changed later (SK97).

24 Xuanyuan (“Yellow Emperor”) is usually only an asterism, which does not have the additional function as LM asterism; given that it seems to be listed here as xiu, it may have some ‘lodge’-like function; Xuanyuan is meant as skeleton of 17 stars in Leo and Lynx starting with α Leo close to the ecliptic.

25 Taiwei (“Great Tenuity Enclosure” or “Supreme Subtlety Palace” or “Privy Council”) is one of three asterisms, which are so-called “enclosures” (yuan) with two “walls” each, Taiwei being a large area with 10 stars in Virgo and eastern parts of Leo (12 stars in Tianguan shu, but then only 10 in the official Shi Shi, SK97); the determinative star of Taiwei is Youzhifa (β Vir) at the southern end of Taiwei’s western wall (SK97).

26 Stephenson and Yau (1985) and Yeomans et al. (1986) thought that, in addition to the comet seen since AD 760 May 16/17, there would have been another comet seen in the south or west since May 20/21.

Image of Chinese Texts from Neuhauser et al (2021)

from Neuhauser et al (2021:Fig. 16)
The Chinese texts from JTS, THY, and XTS on the comet of AD 760 (see Section 3).

The Chinese texts from JTS, THY, and XTS on the comet of AD 760

Chronology


Date	Reference	Corrections	Notes
May 760 CE	Pseudo-Dionysius of Tell-Mahre - The year one thousand and seventy-one: In the month of Adar (March), a shining sign was seen in the sky before dawn on the northeast side which is called Ram in the Zodiac, to the north of the three most shining stars. Its shape resembled a broom.	month of Adar changed to Iyyar	A.G. 1071 converted to CE using CHRONOS
1 Sept. 759 to 31 Aug.760 CE	Theophanes - A.M. 6252 ... In the same year a very bright comet appeared for ten days in the east and another twenty-one days in the west	none	A.M._a 6252 converted to CE using CHRONOS Other Chronological Pointers (i.e. regnal years) in Theophanes are ignored. Theophanes' multiplicity of time markers are often in disagreement creating chronological confusion and imprecision. However, because his regnal year markers are consistently displaced by 4 years between the By No Means Mild Quake of 756 CE and Halley's Comet of 760 CE, these markers have more value as relative rather than absolute markers of time. This is discussed briefly in this section (Pseudo-Dionysius of Tell-Mahre, Theophanes, and the Comet of 760 CE) Chronological Discussion from Neuhauser et al (2021:17) Neuhauser et al (2021:17) A duration of 10 days in the east (before conjunction with the Sun) and 21 days in the west (after conjunction) is slightly shorter but consistent with the reports from Zuqnın (and China) for the comet of AD 760. Theophanes’ chronology is sometimes uncertain by 1–2 yr (Mango and Scott, 1997) – here one year, since the Byzantine year runs from 760 Sep 1 to 761 Aug 31¹. Footnotes 1 JW: This assumes that Theophanes started his year on Sept. 1 instead of 25 March. According to Grumel (1934:398-402), A.M._a 6252 falls within Synchronism MB when the year starts on 1 Sept.
22 April - 21 May 760 CE	Nu'aym ibn Ḥammmad - We saw the comet rising in Muḥarram in the year [Anno Hijra, AH 145 = AD 762/3] with the dawn from the east, and we would see it during the dawn for the rest of Muḥarram; then it disappeared.	A.H. 145 corrected to A.H. 143 - see Chronological Discussion.	Muḥarram A.H. 143 calculated using CHRONOS. Chronological Discussion from Neuhauser et al (2021:17) and Cook (1999:136) Neuhauser et al (2021:17) Given other dating errors in this quite apocalyptic Hadith collection, it may be dated to AH 143, i.e. AD 760/1 (Cook, 1999). With new-moon on 760 Apr 20 and May 19, the month of Muḥarram would run from AD 760 about Apr 21 to May 20 (±1 or 2 days depending on the first detection of the crescent moon), but the comet of AD 760 did not disappear at around May 20. However, the source used by Nu'aym ibn Ḥammad could have given the date on a western calendar system, e.g. as May, which would have been converted loosely to Muḥarram, probably based on a Christian source using e.g. the West Syrian Seleucid calendar as, e.g., the Chronicle of Zuqnın. A scribal error is then required only for the year number (AH) “145”, which should be 143. Then, the text would be fully consistent with the Chronicle of Zuqnın: seen first since some time in the month of May of AD 760 in the morning dawn (“with the dawn”, Zuqnn: “safro”) in the east and also like that for the rest of that month “during the dawn” (Zuqnın: “nogah”) – instead of “rest of Muḥarram”, we should read “rest of iyyor/May”; the Chronicle of Zuqn ̄ın reported the last visibility before conjunction with the Sun for the early morning of the night May 31/June 1 (“Pentecost”). Then, according to Nu'aym the comet was seen after conjunction “after the sunset in the twilight between the north and the west for two month or three”, i.e. again similar as in Zuqnın (for 25 evenings in the NW and later again for “many days”), after conjunction the comet was definitely seen in two different months (June and July). When Nu'aym ibn Ḥammad mentioned a reappearance “two or three years” later, he could either mean some other comet or transient object, or he could have interpreted the text in the Chronicle of Zuqnın, which is found in the report for SE 1075 (AD 763/4), which is, however, again about the comet of AD 760: “The effect of ’the broom’ seen a short while before, was clearly seen in reality, as it swept the world like a broom that cleans the house” (Harrak, 1999), see Section 2.1 for full citation (given that the Chronicle of Zuqnın does not mentioned any other comet or celestial sign in between the comet report in AD 760 and this short statement later, it is likely that the latter short note points to the comet of AD 760). Therefore, given all the similarities (except the offset by 2 years), it is likely that the (direct or indirect) source used by Nu'aym ibn Ḥammad is the Chronicle of Zuqnın – this would be the first hint that our chronicle was active before been buried in a Sinai monastery in the 9th century. Cook (1999:136) It is very likely because of the tradition in Theophanes that there was a mistake made in the date here (since there are a great many errors in this edition of the apocalyptic text), and that the real date is 143/760.²² According to the Chinese records of this appearance it began on 16 May (corresponding to 24 Muharram of that year) and lasted into July. This would be consistent with our tradition, which continues to detail several other comets. Footnotes (22) I can't find the footnotes in this article.
760 CE	Agapius of Menbij - In this year [AD 760] the star with a tail appeared, and it was in Aries before the Sun, and the Sun was in Taurus. It proceeded until it was under the rays of the Sun, then went behind it and stayed 40 days	none	“and in this year” equated to [AD 760] by Neuhauser et al (2021:17) Chronological Discussion from Neuhauser et al (2021:17) Neuhauser et al (2021:17) Cook remarks: “This observation is probably from Theophilus of Edessa himself”. (Note that Cook (1999) incorrectly gave “and the Sun was in Leo”, while the text clearly gives Taurus, see Vassiliev, 1911.)
May 755 CE - May 765 CE	Michael the Syrian - And in this year in the month of iyyor (May), a comet star [kawkbo qumiṭus – the latter obviously from the Greek kometes] was seen before the Sun in Lamb (Aries), when the Sun was in Taurus.	“and in this year” equated to A.G. 1066-1076 - see Chronological discussion.	Iyyor equates to May in the Syriac calendar. A.G. 1066-1076 converted to a time span in CE using CHRONOS. See below why this time span was used. Chronological Discussion from Neuhauser et al (2021:19) Neuhauser et al (2021:19) The expression “and in this year” refers to SE 1076 (AD 764/5), if related to the preceding account which deals with an earthquake in Khorasan. However, chapter 25 of Michael the Syrian, in which the comet report appears, covers the period from SE 1066 to 1076 – this cast doubt about the expression “and in this year”. When Michael the Syrian quotes large texts, he names his sources, but when he gathers information to include in a Chapter, he picks and copies, but not necessarily in chronological order.

Figures and Tables

Notes

Kepler Orbit (Wikipedia)

from Wikipedia

Chronicle of Theophanes

Background and Biography

Excerpts

English from Mango and Scott (1997)

from Mango and Scott (1997:594-595)

[A.M. 6248, AD 755/6]

Constantine, 16th year
Abdelas, 2nd year
Paul, 2nd year
Constantine, 3rd year

II In this year, on 9 March, there occurred a considerable earthquake in Palestine and Syria.II^a Theodore [I], patriarch of Antioch, was exiled because of the malice of the Arabs, having been accused of frequently communicating Arab affairs by letter to the emperor Constantine. And so, Salim¹ himself banished him to the land of Moab which was his native country. The same Salim decreed that no new churches should be built, that crosses should not be displayed and that Christians should not discourse with Arabs on matters of religion. II He invaded the Roman country² with a force of 80,000 and, when he had come to Cappadocia, he heard that Constantine was taking up arms against him. Taking fright, he returned empty-handed without causing any damage, except that he took a few Armenians who had joined him. II^b.

Footnotes

a Ps.-Dion. Chron. 63 records an earthquake in Mesopotamia on 3 Mar. AG 1067.
b Cf. Agapios, 278, with different details.

1 Salih b. 'All. He was governor of Egypt down to AH 140 (757/8). In AH 141 (758/9) he was appointed over Qinnasrin (Chalkis), Emesa, and Damascus: Tabari, Williams, i. 28, 31, 36, 44. His measures against the Christians, including the patriarch of Antioch, would thus appear to date from 758/9.

2 Salih led two expeditions to rebuild Melitene, the first in AH 138 (755/6), the second the following year (which is probably the one meant here). On the latter occasion he entered Byzantine territory by the pass of Adata: Tabari, Williams, i. 29, 32. Cf. Brooks, 'Abbasids', 733.

English from Mango and Scott (1997) - embedded

see [A.M. 6248, AD 755/6] on page 594
from Mango and Scott (1997:594-595)
from archive.org

English from Turtledove (1982) - embedded

see ANNUS MUNDI 6248 starting on page 119
from Turtledove (1982:119)
from archive.org

Chronology

Halley’s Comet of 760 CE shows that Theophanes' A.M._a is correct and the year was 756 CE.

Year (CE)	Reference	Corrections	Notes
9 March 756 CE	on 9 March A.M._a 6248	none	Calculated with CHRONOS extra year not added because Halley’s Comet of 760 CE shows that Theophanes' A.M._a is correct. See Pseudo-Dionysius of Tell-Mahre, Theophanes, and the Comet of 760 CE for details.
9 March 757 CE	on 9 March Constantine, 16th year	none	Calculated with CHRONOS reign started 18 June 741 CE
9 March 756 CE	on 9 March Abdelas, 2nd year	none	Calculated with CHRONOS reign started on 10 June 754 CE
9 March 759 CE	on 9 March Paul, 2nd year	none	Calculated with CHRONOS consecrated on 29 May 757 CE
9 March 756 or 9 March 757 CE	on 9 March Constantine, 3rd year	none	Calculated with CHRONOS installed 754 CE
9 March 759 CE	Salim's measures against Christians and Theodore [I] exiled	none	Mango and Scott (1997:594-595) suggest this would have happened in A.H. 141 A.H. 141 went from 14 May 758 CE - 3 May 759 CE (calculated with CHRONOS)
9 March 757 CE	Salim invaded the Roman country	none	Mango and Scott (1997:594-595) suggest this happened in A.H. 139 A.H. 139 went from 5 June 756 CE - 24 May 757 CE (calculated with CHRONOS)

Seismic Effects

there occurred a considerable earthquake in Palestine and Syria

Locations

Palestine
Syria

Sources

Online Versions and Further Reading

References

Notes

Theophanes' Calendaric Inconsistencies

Muslim Writers - Meadows of Gold and Mines of Gems by al-Masudi

مُرُوج ٱلذَّهَب وَمَعَادِن ٱلْجَوْهَر by ٱلْمَقْدِسِي by أَبُو ٱلْحَسَن عَلِيّ ٱبْن ٱلْحُسَيْن ٱبْن عَلِيّ ٱلْمَسْعُودِيّ

Aliases

Aliases	Aliases
al-Masudi	أَبُو ٱلْحَسَ
Abū al-Ḥasan ʿAlī ibn al-Ḥusayn ibn ʿAlī al-Masʿūdī	أَبُو ٱلْحَسَن عَلِيّ ٱبْن ٱلْحُسَيْن ٱبْن عَلِيّ ٱلْمَسْعُودِيّ

Background and Biography

Excerpts

English from Lunde and Stone (1989)

an abridged English translation from Lunde and Stone (1989:389)

QAHIR DEMANDS A TRUE HISTORY OF THE CALIPHATE

The following story originates from Muhammad ibn Ali al-Misri, the historian and native of Khurasan, who was an intimate of Qahir:

... It was Mahdi who rebuilt the mosque at Mecca and that of the Prophet at Medina in the form they stand today, and he rebuilt Jerusalem, which had been devastated by earthquakes.

Chronology


Date	Reference	Corrections	Notes
Before 785 CE	[Caliph al-Mahdi (r. 775-785 CE)] rebuilt Jerusalem, which had been devastated by earthquakes.	none

Seismic Effects

he rebuilt Jerusalem, which had been devastated by earthquakes.

Locations

Jerusalem

Online Versions and Further Reading

References

Muslim Writers - Description of Syria including Palestine by al-Maqdisi

وصف سوريا بما في ذلك فلسطين (?) by ٱلْمَقْدِسِي

Aliases

Aliases	Aliases
al-Muqaddasi	ٱلْمَقْدِسِي
Shams al-Dīn Abū ʿAbd Allāh Muḥammad ibn Aḥmad ibn Abī Bakr al-Maqdisī	شَمْس ٱلدِّيْن أَبُو عَبْد ٱلله مُحَمَّد ابْن أَحْمَد ابْن أَبِي بَكْر ٱلْمَقْدِسِي
Shams al-Dīn Abū ʿAbd Allāh Muḥammad ibn Aḥmad ibn Abī Bakr al-Banna' al-Shami
al-Bashshari

Background and Biography

Excerpts

Here we can read about earthquake damage inflicted on Al-Aqsa mosque from more than one earthquake.

English from Le Strange (1886)

from Le Strange (1886:41)

But in the days of the Abbasides occurred the earthquakes which threw down most of the main building; all, in fact, except that portion round the Mihrab. Now when the Khalifa of that day obtained news of this, he enquired and learned that the sum at that time in the treasury would in no wise suffice to restore the mosque. So he wrote to the Governors of the Provinces and to other Commanders, that each should undertake the building of a colonnade.

English from Le Strange (1886) - embedded

see middle of page 41 starting with But in the days of the Abbasides
from Le Strange (1886:41)
from archive.org

Chronology

Year	Reference	Corrections	Notes
after 25 Jan. 750 CE	in the days of the Abbasides	none

Seismic Effects

Earthquakes (plural) are mentioned
threw down most of the main building of Al-Aqsa mosque in Jerusalem
only the part of the Mosque around the Mihrab was spared

Locations

Jerusalem - Al Aqsa Mosque

Online Versions and Further Reading

References

Muslim Writers - The Best Divisions in the Knowledge of the Regions by al-Maqdisi

أفضل الأقسام في معرفة المناطق (?) by ٱلْمَقْدِسِي

Aliases

Aliases	Aliases
al-Maqdisi
al-Muqaddasi	ٱلْمَقْدِسِي
Shams al-Dīn Abū ʿAbd Allāh Muḥammad ibn Aḥmad ibn Abī Bakr al-Maqdisī	شَمْس ٱلدِّيْن أَبُو عَبْد ٱلله مُحَمَّد ابْن أَحْمَد ابْن أَبِي بَكْر ٱلْمَقْدِسِي
Shams al-Dīn Abū ʿAbd Allāh Muḥammad ibn Aḥmad ibn Abī Bakr al-Banna' al-Shami
al-Bashshari

Background and Biography

Excerpts

English from Collins (2001)

from Collins (2001:275-276)

Jerusalem (Baitu-l-Maqdis)

... The Masjidu-l-Aqsa⁴ (the Furthest Mosque) lies at the south-eastern corner of the city. Its foundations were laid by David, each stone being ten cubits, or a little less in length. The stones are chiselled, finely faced, and jointed, and of hardest material. On these foundations ‘Abdu-l-Malik subsequently built,⁵ using smaller but well-shaped stones and battlements were added above. This mosque was even more beautiful] than that of Damascus,¹ but in the days of the ‘Abbäsides an earthquake occurred which threw down most of the main building; all, in fact, except the part around the mihräb. Now when the Caliph of that day² obtained news of this, he enquired and learned the not all the sums in the treasury would suffice to restore the mosque to its former state. So he wrote to the Governors of the Provinces and to other Commanders, directing that each should undertake the building of a colonnade. The order was carried out, and the edifice rose firmer though less elegant than it had been; and the more ancient portion remained, even like a beauty spot, in the midst of the new.

Footnotes

4 So. called from Qur'än xvii.l. The name al-Aqsä originally applied to the whole temple area, but is now generally confined to the building at the south end of the Haram. It was built by order of the caliph ‘Umar, on the site of Justinian’s church of St. Mary.‘ The great sanctuary of Jerusalem is now known as the Mosque of ‘Umar.

5 The Mosque was commenced in A.D. 683, and completed in three years.

1 MS. C adds: For during the building of it they had for a rival and as a comparison the great church (the Church of the Holy Sepulchre) belonging to the Christians at Jerusalem, and they built this to be even more magnificent than that other.

3 Said to have been the caliph al-Mahdi (AD. 774-785); but after the great earthquake, it was al-Ma’mün who restored the buildings of the sanctuary. His name is still rend on a Cufic inscription on the Dome of the Rock.

Chronology

Year	Reference	Corrections	Notes
after 25 Jan. 750 CE	in the days of the Abbasides	none

Seismic Effects

in the days of the ‘Abbäsides an earthquake occurred which threw down most of the main building [Al Aqsa Mosque]; all, in fact, except the part around the mihrab

Locations

Jerusalem - Al Aqsa Mosque

Online Versions and Further Reading

References

The Complete History by Ibn al-Athir

الكامل في التاريخ by علي عز الدین بن الاثیر الجزري

Aliases

Aliases	Aliases
Ibn al-Athir	الدین بن
Ali 'Izz al-Din Ibn al-Athir al-Jazari	علي عز الدین بن الاثیر الجزري
Abu al-Hassan Ali ibn Muhammad ibn Muhammad ash-Shaybani

Background and Biography

Excerpts

Characterization in English from Taher (1996)

from Taher (1996)

140/757 : earthquakes in al-Massîsa ; the surrounding wall is weakened. The caliph al-Mansûr decrees the reconstruction of al-Massisa under the responsibility of Djibrayl b. Yahya . The inhabitants of this town were few in number. The wall was rebuilt and the city was called al- Ma`mûra . The construction manager builds a large mosque. He paid the wages of 1000 workers⁶⁷.

Footnotes

67 B. al-Athîr , al-Kâmil , 5/500. This is the ancient Greek city of Mopsuestia, cf. Honigmann , EI, t. III, p. 591-596.

Poirier and Taher (1980)'s Ibn al-Athir references

Poirier and Taher (1980) list Ibn al-Athir as a source for an earthquake in AH 140 (25 May 757 to 13 May 758 CE) in Msis (Mopsuestia).

(7) Ibn Al Athir Abu Hassan 'Ali
· "Al Kamil fi at Tarikh", edited by Tornberg, Leyden, 1851-1876.
· "al Tarikh al Bahir fi ad Dawla al Atabikya", edited by Tolymat, Cairo, 1963.

Original Document

Chronology


Year	Reference	Corrections	Notes
25 May 757 - 13 May 758 CE	A.H. 140	none	Calculated with CHRONOS

Seismic Effects

earthquakes in al-Massîsa
the surrounding wall is weakened
The caliph al-Mansûr decrees the reconstruction of al-Massisa under the responsibility of Djibrayl b. Yahya
The inhabitants of this town were few in number
The wall was rebuilt and the city was called al- Ma`mûra
The construction manager builds a large mosque.

Locations

al-Massîsa (Mopsuestia).

Sources

Online Versions and Further Reading

References

The Cream of the History of Aleppo by Ibn al-Adim (aka Kemal ad-Din)

زبدة الحلب في تأريخ حلب by مال الدين عمر بن أحمد ابن العديم

Aliases

Aliases	Arabic
Ibn al-Adim
Kamāl al-Dīn Abu ʾl-Ḳāsim ʿUmar ibn Aḥmad ibn Hibat Allāh Ibn al-ʿAdīm	مال الدين عمر بن أحمد ابن العديم
Kamāl al-Dīn Abu Hafs 'Umar b. Ahmad

Background and Biography

Excerpts

English from Blochet (1895)

from Blochet (1900:46 n.3)

Masisah. Malmistra according to Latin writers; in Armenian Msis.

According to The Description of Aleppo (ms. ar. 1683, fol. 67 r.):

this name includes two towns; between the two flows the Djihân river, the western city is Masisah, the eastern city Kafr-bîà, it was called the little Baghdad (Baghdâd as-Soghrâ)

Ibn abi-la'koûb said:

It was built by al-Mansoûr during his caliphate. It was a simple post before him. Al-Mamoûn builds Kafr-bîà; the Djihân river flows between the two places; on this stream there is an old bridge, large and built in stone.

According to the same author, the citadel of Masisah was built during the reign of Abd al-Malik ibn-Marwân; there was a church that 'Omar ibn' Abd al-'Azîz destroyed. This person had the mosque djâmi built for the locals in the vicinity of Kafr-bîâ. Hishâm ibn 'Abd al-Malik built the suburb of the city that suffered from the earthquake of the year A.H. 140. We still cite al-Mansoûr and al-Mahdî as the builders of this city ; ar-Rashîd built a ditch there. It was taken from the Muslims in 354 of the Hegira by the takafoûr.

French from Blochet (1895)

from Blochet (1900:46 n.3)

Masisah. La Malmistra des écrivains latins ; en arménien Msis.

Suivant la Description d'Alep (ms. ar. 1683, fol. 67 r.):

ce nom comprend deux villes ; entre les deux coule le fleuve Djîhan, la ville occidentale est Masîsah, la ville orientale Kafr-bîà, on l'appelait la petite Bagdad (Baghdâd as-Soghrâ).

Ibn abi-la'koûb dît :

Elle fut construite par al-Mansoûr durant son khalifat. C'était avant lui un simple poste. Al-Mamoûn bâtit Kafr-bîà ; le fleuve Djihân coule entre les deux places ; sur ce cours d'eau il y a un pont ancien, grand et bâti en pierres.

Suivant le même auteur, la citadelle de Masîsah fut bâtie sous le règne d' 'Abd al-Malik ibn-Marwân ; il y avait une église qu' 'Omar ibn 'Abd al-'Azîz détruisit. Ce personnage fit construire une mosquée djâmi' pour les gens du pays dans les environs de Kafr-bîâ. Hishâm ibn 'Abd al-Malik construisit le faubourg de la ville qui souffrit du tremblement de terre de l'an 140. On cite encore al-Mansoûr et al-Mahdî comme constructeurs de cette ville ; ar-Rashîd y construisit un fossé. Elle fut prise aux Musulmans en 354 de l'hégire par le takafoûr

French from Blochet (1900) - embedded

see footnote 3 on page 46
from Blochet (1900:46 n.3)
from archive.org

Chronology


Year	Reference	Corrections	Notes
25 May 757 - 13 May 758 CE	A.H. 140	none	Calculated with CHRONOS

Seismic Effects

the suburb of the city that suffered from the earthquake of the year A.H. 140

Locations

Masisah (Mopsuestia).

Sources

Online Versions and Further Reading

References

Earthquake in Mopsuestia in A.H. 139 according to an unknown Muslim source

Background and Biography

Le Strange (1905:130-131) did not cite his source.

Excerpts

English from Le Strange (1905)

from Le Strange (1905:130-131)

Al-Massisah lies on the Nahr Jayhan (the river Pyramus). It was conquered by 'Abd-Allah, son of the Omayyad Caliph 'Abd-al- Malik, in the 1st (7th) century, who rebuilt its fortifications and established a strong garrison here. A mosque was erected on the summit of the hill, and the church in the fortress was turned into a granary. A suburb or second town was built shortly afterwards on the other bank of the Jayhan, called Kafarbayya, where the Caliph Omar II founded a second mosque and dug a great cistern. A third quarter, lying to the east of the Jayhan, was built by the last Omayyad Caliph Marwan II, and named Al-Khusus ; he surrounded it by a wall with a ditch, and wooden doors closed its gateways. Under the Abbasids the Caliph Mansur turned an ancient temple into a Friday Mosque, making it thrice as large as the older mosque of Omar II. Harun-ar-Rashid rebuilt Kafar-bayya, and its mosque was further enlarged by Mamun. The two quarters of Kafarbayya, and Massisah proper were connected by a stone bridge across the Jayhan ; the town bore the title of Al-Ma'muriyah, 'the Populous,' or 'Well-built,' said to have been bestowed upon it by the Caliph Mansur, who restored Massisah after it had been partially destroyed by earthquake in [A.H.] 139 (5 June 756 to 24 May 757 CE). At a later date Massisah, like its neighbours, passed into the possession of the kings of Little Armenia.

English from Le Strange (1905) - embedded

see bottom paragraph of page 130 starting with The three cities of Al-Mass!sah (Mopsuestia), Adhanah (Adana)
from Le Strange (1905:130-131)
from archive.org

Chronology


Year	Reference	Corrections	Notes
5 June 756 to 24 May 757 CE	A.H. 139	none	Calculated with CHRONOS

Seismic Effects

Caliph Mansur, who restored Massisah after it had been partially destroyed by earthquake in [A.H.] 139

Locations

Massisah (Mopsuestia)

Online Versions and Further Reading

References

The Lands of the Eastern Caliphate: Mesopotamia, Persia, and Central Asia from the Moslem Conquest to the Time of Timur, Cambridge, 1905; tr. Maḥmud ʿErfān, as Joḡrāfiā-ye tāriḵi-e sarzaminhā-ye ḵelāfat-e šarqi, Tehran, 1970.

Guy Le Strange at Encyclopedia Iranica

Guy Le Strange at wikipedia - has links to his works

Muslim Writers - The Exciter of Desire (for Visitation of the Holy City and Syria) by Jamal ad Din Ahmad

موتهير الءعهيرام (Muthîr al-Ghirâm) by جامال اد دين اهماد (?)

Aliases

Aliases	Aliases
Jamal ad Din Ahmad	جامال اد دين اهماد (?)

Background and Biography

Excerpts

English from Le Strange (1890)

from Le Strange (1890:92)

On the authority of 'Abd ar Rahman ibn Muhammad ibn Mansur ibn Thabit, from his father, who had it from his father and grandfather. In the days of 'Abd al Malik, all the gates of the mosque were covered with plates of gold and of silver. But in the reign of the Khalif Al Mansur, both the eastern and the western portions of the mosque had fallen down. Then it was reported to the Khalif, saying,

O commander of the faithful, verily the earthquake in the year 130 (a.d. 746) did throw down the eastern part of the mosque and the western part also; now, therefore, do thou give orders to rebuild the same and raise it again.

Khalif replied that as there were no moneys in his treasury, (to supply the lack of coin) they should strip off the plates of gold and of silver that overlaid the gates. So they stripped these off and coined therefrom Dinars and Dirhams, which moneys were expended on the rebuilding of the mosque until it was completed. Then occurred a second earthquake, and the building that Al Mansur had commanded to be built fell to the ground. In the days of the Khalif Al Mahdi, who succeeded him, the mosque was still lying in ruins, which, being reported to him, he commanded them to rebuild the same. And the Khalif said that the mosque had been (of old) too narrow, and of too great length - and (for this reason) it had not been much used by the people — so now (in rebuilding it) they should curtail the length and increase the breadth. Now the restoration of the mosque was completed on the new plan during the days of his Khalifate.

English from Le Strange (1890) - embedded

see bottom paragraph on page 92 starting with On the authority of 'Abd ar Rahman ibn Muhammad ibn Mansur ibn Thabit
from Le Strange (1890:92)
from archive.org

Chronology

**1st Earthquake**
Year	Reference	Corrections	Notes
11 September 747 - 30 August 748 CE	A.H. 130	none	Calculated with CHRONOS

**2nd Earthquake**
Year	Reference	Corrections	Notes
Between 10 June 754 and 24 July 785 CE	After the rebuild by Caliph Al-Mansur (r. 10 June 754 – 6 October 775 CE) and before the second rebuild by Caliph Al-Mahdi (r. 6 October 775 – 24 July 785 CE)	none

Seismic Effects

1st Earthquake

the earthquake in the year 130 did throw down the eastern part of the mosque and the western part also

2nd Earthquake

Then occurred a second earthquake, and the building that Al Mansur had commanded to be built fell to the ground

Locations

1st Earthquake

Al Aqsa Mosque - Jerusalem

2nd Earthquake

Al Aqsa Mosque - Jerusalem

Online Versions and Further Reading

References

Muslim Writers - The Glorious History of Jerusalem and Hebron by Mujir al-Din

التاريخ المجيد للقدس والخليل (?) by مجير الدين

Aliases

Aliases	Aliases
Mujir al-Din al-’Ulaimi	مجير الدين العليمي (?)
al-’Ulaimi	العليمي (?)
'Abd al-Rahman ibn Muhammad al-'Ulaymi	مجير الدين عبدالرحمن الحنبلي العليمي الشهير بأبن قطينه (?)
Ibn Quttainah	يبن قوتتايناه (?)

Background and Biography

Excerpts

English from Ambraseys (2009) - an account of the earthquake which destroyed Al Aqsa Mosque the 1st time

from Ambraseys (2009)

The history of the holy Rock at Jerusalem on the night of the earthquake, according to Abu Umayr who held the Jundub which pertained to Rustum al- Farisi:

At the time when the first earthquake occurred, they requested me to give the call to prayer, and I answered that that was not my business. They asked me the same when the second [earthquake] occurred and I gave the same answer. Come the third earthquake, I was very frightened and I approached the mosque. All the houses had been destroyed. One of the guards of the holy Rock asked me, 'Quick, go and get news of my family and I will tell you the prodigy.' I went to find out and brought him back the news. Then he said to me, 'The dome lifted itself up, [so that] one could see the stars in the sky, and then it settled again. I heard some unknown people giving orders: here, a bit more, since it was not in its correct place.

According to another version (that of ‘Ubayd Allah ibn Muhammad al-Qaramany), taken from Amr and Rustum himself:

There were ten guards at each gate: when I brought him news of his family, my guard related to me that the dome had been dropped down (depose´), [so] that the stars had been visible, and that before I returned, rustlings had been heard, then a voice saying ‘Put it down’ three times, and the dome was put back in its place.

Al-Walid ibn Hamad gives an account taken from Abd ar-Rahman ibn Muhammad ibn al-Mansur ibn Thabit, who gives the following version passed down from his father and grandfather:

Abu ‘Uthman was sounding the evening prayer, after the prayer of Qyam [the breaking of the fast], on the black square. During the evening prayer, he heard the roar of an earthquake, and cries of people’s distress across the town. It was a black and cold night, full of rain and wind. He heard a voice (without seeing anyone) which said, “Lift it up gently, in the name of God”, and the dome was lifted up so that the stars appeared, and at the same time people felt drops of water on their faces, until the time of the call to prayer. After this the voice said, “Put it down, put it in place, in the name of God.” And the dome returned to its place.

(al-’Ulaimi, al-Uns. i. 237–238).

English from Sauvaire (1876) - accounts of two instances of seismic damage and repairs made to Al Aqsa mosque

from Sauvaire (1876:59)

Abd-er-Rahman ibn Mohammad ibn Mansoûr ibn Tàbet reported from his father who reports from his grandfather that all the doors [of Al-Aqsa Mosque] were covered with gold and silver plates up to the time of Abd-el-Malek. Now, when the Abbasid Abu-Dja'far El-Mansoûr came, the eastern and western parts of the mosque had fallen. He said [to the Caliph]:

Commander of the Believers, the eastern and western parts of the mosque were overthrown by the earthquake in the year 130. If you gave the order to rebuild this Mosque and restore it, I do not have the money [to do so].

Then he [the Caliph] ordered him to tear off the gold and silver plates which covered the doors. They were torn off and they made dinars and dirhams which were used for the expenses of the reconstruction until it was completed.

The caliphate of El-Mansoùr began in the year 136. He was the second caliph of the Abbasids who built Baghdad. Construction started in the year 145. He [El-Mansoùr] died on Saturday the 6th of the month of Dhu l'Hijja, year 158 (AD October 7, 775), at the age of fifty-eight years and was buried in Mecca.

Some time later the second earthquake struck and overturned the buildings executed by the order of Abu-Dja'far. Subsequent to this time, that is to say after the death of the Caliph, [the new Caliph] El-Mahdy came and with the constructions in ruins, the state of things was explained to him. He ordered repairs saying:

This Mosque is narrow and long and empty of followers. Decrease the length and make it wider.

The building was completed under his caliphate. His full name is Abu-'Abd-Allah Mohammad, son of Abd-Allah El-Mansoûr, and his honorary nickname is El-Mahdy.

French from Sauvaire (1876) - accounts of two instances of seismic damage and repairs made to Al Aqsa mosque

from Sauvaire (1876:59)

'Abd-er-Rahman ebn Mohammad ebn Mansoûr ebn Tàbet a rapporté d'après son père qui le tenait de son aïeul, que toutes les portes étaient revêtues de plaques d'or et d'argent à l'époque d' 'Abd-el-Malek. Or, lorsque vint Abou-Dja'far El-Mansoûr. l'Abbâsîde, les parties orientale et occidentale du Masdjed étaient tombées : « Com- mandeur des Croyants, lui dit-on_, les parties orientale et occidentale du Masdjed ont été renversées par le tremblement de terre, en l'année 130; si tu donnais l'ordre de reconstruire ce Masdjed et de le restaurer ? — Je n'ai pas d'argent, » répondit-il. Puis, il ordonna d'arracher les plaques d'or et d'argent qui recouvraient les portes. Elles furent arrachées, et on en fabriqua des dinars et des derhems qui servirent aux dépenses de la reconstruction, jusqu'à ce que celle-ci fut achevée.

Le khalifat d'El-Mansoùr commença en l'année 136. Deuxième khalife des 'Abbâsides, c'est lui qui construisit Baghdàd; la construction en fut commencée l'an 145. Il mourut le samedi 6 du mois de dou'l heddjeh, l'année 158 (7 octobre 775 de J.-C.), à l'âge de cinquante-huit ans, et fut enterré à la Mekke.

Quelque temps après eut lieu le second tremblement de terre qui renversa les constructions exécutées par l'ordre d'Abou-Dja'far. Postérieurement à cette époque, c'est-à-dire après la mort du khalife, El-Mahdy étant venu et ces constructions se trouvant en ruines, on lui exposa l'état des choses: il ordonna de faire les réparations, en disant: « Ce Masdjed est étroit et long, et vide de fidèles; diminuez-en la longueur et faites-le plus large. » La bâtisse fut achevée sous son khalifat. Son nom entier est Abou-'Abd-Allah Mohammad, fils d' 'Abd-Allah El-Mansoûr, et son surnom honorifique El-Mahdy.

French from Sauvaire (1876) - accounts of two instances of seismic damage and repairs made to Al Aqsa mosque - embedded

see 1st complete paragraph on page 59 starting with 'Abd-er-Rahman ebn Mohammad ebn Mansoûr ebn Tàbet
from Sauvaire (1876:59)
from archive.org

Original Document - Arabic - embedded

not bookmarked

Chronology

Dates for the two earthquakes which damaged Al Aqsa Mosque

**Earthquake which damaged Al Aqsa Mosque the 1st time**
Year	Reference	Corrections	Notes
11 September 747 - 30 August 748 CE	A.H. 130	none	Calculated with CHRONOS

**Earthquake which destroyed Al Aqsa Mosque the 2nd time**
Year	Reference	Corrections	Notes
10 June 754 – 6 October 775 CE	Sometime during the reign of Caliph Al-Mansur (r. 10 June 754 – 6 October 775)	none	The caliphate of El-Mansoùr began in the year 136 (specifically 10 June 754 CE) Some time later the second earthquake struck and overturned the buildings Subsequent to this time, that is to say after the death of the Caliph, [the new Caliph] El-Mahdy (r. 6 October 775 – 24 July 785) came and with the constructions in ruins, the state of things was explained to him He (El-Mahdy) ordered repairs Notes Reference in Sauvaire (1876:59) to construction starting in A.H. 145 refers to building in Baghdad and not to Al Aqsa Mosque. There is a possibility that the Earthquake which destroyed Al Aqsa Mosque the 2nd time struck during the reign of Al-Mahdi (r. 6 October 775 – 24 July 785)

The Main Shock from the Earthquake which damaged Al Aqsa Mosque the 1st time struck at night

Three instances of eyewitness testimony sourced through a chain of witnesses (isnad) describes a main nighttime shock. A nighttime earthquake is compatible with the timing of the Holy Desert Quake reported by al-Muqaffa, Al-Makin, Chronicon Orientalen, and Pseudo-Dionysius of Tell-Mahre. The table below summarizes eyewitness testimony for a nighttime earthquake.

**Earthquake which damaged Al Aqsa Mosque the 1st time struck at night**
Source	Quotes
Abu Umayr	The dome lifted itself up, [so that] one could see the stars in the sky
‘Ubayd Allah ibn Muhammad al-Qaramany	the dome had been dropped down, [so] that the stars had been visible,
Al-Walid ibn Hamad	Abu ‘Uthman was sounding the evening prayer, after the prayer of Qyam [the breaking of the fast] During the evening prayer, he heard the roar of an earthquake, and cries of people’s distress across the town It was a black and cold night, full of rain and wind the dome was lifted up so that the stars appeared at the same time people felt drops of water on their faces, until the time of the call to prayer Notes The account from Al-Walid ibn Hamad states that the earthquake struck during an evening prayer that happened after the prayer of Qyam [the breaking of the fast]. It appears that the prayer of Qyam can take place any time during the night. Caveat : the earthquake was described as striking on a black and cold night, full of rain and wind yet the same earthquake breached the roof of Al Aqsa Mosque such that the stars appeared and at the same time people felt drops of water on their faces. How likely is it that one can see the stars on a black rainy night ?

Foreshocks from the Earthquake which damaged Al Aqsa Mosque the 1st time

Two earlier daytime foreshocks were also described according to Abu Umayr.

**Descriptions of Foreshock timing**
Shock Number	Quotes
1	At the time when the first earthquake occurred, they requested me to give the call to prayer,
2	They asked me the same (give the call to prayer) when the second [earthquake] occurred

The foreshocks are described as occurring soon before calls to prayer. Muslim prayer times are shown below.

**Muslim Prayer Times**
Prayer Name	Prayer Time
Fajr prayer	~ 6 am - between dawn and sunrise
Zuhr prayer	12 pm - noon
Asr prayer	~ 3 pm - midway between noon and sunset
Maghrib prayer	~ 6 pm - just after sunset
Isha prayer	~ 7 pm - nighttime

Seismic Effects

Earthquake which damaged Al Aqsa Mosque the 1st time

All the houses had been destroyed
The dome [of Al Aqsa Mosque] lifted itself up, [so that] one could see the stars in the sky, and then it settled again
the dome had been dropped down, [so] that the stars had been visible
he heard the roar of an earthquake, and cries of people’s distress across the town
the eastern and western parts of the mosque were overthrown by the earthquake in the year 130

Earthquake which damaged Al Aqsa Mosque the 2nd time

Some time later the second earthquake struck and overturned the buildings

Locations mentioned

Earthquake which damaged Al Aqsa Mosque the 1st time

Jerusalem

Earthquake which damaged Al Aqsa Mosque the 2nd time

Jerusalem

Sources

Online Versions and Further Reading

References

Notes

Chains of Transmission in Mujir ad-Din

Notes

Megas Chronographos

Guidoboni et al (1994:370) indicates that this earthquake is referred to in Megas Chronographos 12, but Megas Chronographos 12 refers to the Sabbatical Year Quakes - see Megas Chronographos in the Sabbatical Year Quakes.

Habura

Map showing location of Habura (aka Khabur) River

Syria 2004 CIA map

Wikipedia - קרלוס הגדול - CC BY-SA 3.0

Guidoboni et al (1994:371) adds the following notes about Pseudo-Dionysius of Tell-Mahre's account

It has not been possible to identify the site of Habura. The only indication provided by the editor of the text of Pseudo-Dionysius of Tellmahre is a reference to the Thesaurus Syriacus (Payne Smith 1879, I, col.1172), which laconically reports: name of a city.

Habura (aka Khabur) is a tributary of the Euphrates River and is located in northern Mesopotamia (Jazira). Guidoboni et al (1994:370-371) wrote before Harrak (1999)'s translation of Pseudo-Dionysius was available so I will assume that Habura has now been identified as Khabur.

Ambraseys (2009)

AD 757 Massisa, Kafr-bia

An earthquake damaged Kafr-bia, and probably Misis. This earthquake is known only from a decree Al-Mansur issued for the rebuilding of al-Massisah following an earthquake in a.H. 140 (25 May 757 to 13 May 758). He comments that the inhabitants of the town were ‘not very numerous’. Whether this was due to the earthquake or simply reflected the fact that the town was in decline is not known.

Le Strange adds that Misis was partially destroyed by earthquake a year earlier in a.H. 139 (5 June 756 to 24 May 757); he quotes no authority (Le Strange 1905; Blochet 1895, 554 n. 3).

Notes

‘(a.H. 140) Al-Mansur decreed the rebuilding of al-Massisah in the charge of Jibra’il ibn Yahya: the girdle-wall had been weakened by the earthquake. The inhabitants of this town were not very numerous. The wall was rebuilt and called al-Ma’mura. And the clerk of the works built a great mosque. He paid the salary of 1000 workmen and allowed many of the inhabitants to set up home inside the girdle-wall.’ (MS Ar. 1683. 67r, in Blochet 1895).

References

Ambraseys, N. N. (2009). Earthquakes in the Mediterranean and Middle East: a multidisciplinary study of seismicity up to 1900.

Sbeinati et al (2005)

〈050〉 757 March 9

Habura: VII
Mesopotamia
Syria
Palestine

Surface faulting and liquefaction in Mesopotamia
Landslide at Mount Tabor

Sources

Theophanes: A strong earthquake in Syria and Palestine.

Chronicon Pseudo-Dionysus of Tell-Mahre: A big and terrible shock in the region of Mesopotamia. Near Harbura, three villages fell down.

Seismological compilations

Guidoboni et al. (1994): 757 March 9, Habura, Palestine, Syria and Mesopotamia I = IX. A powerful earthquake struck Syria and Palestine on 9 March 757 (Theophanes). In the year 756 on Tuesday 3 March, there was a great, violent and terrible earthquake in the land of Mesopotamia where three villages near Habura collapsed, many people there were crushed and perished (Pseudo-Dionysius).

Russell (1985): An earthquake by no means mild, affected Palestine and Syria on 9 March 757 (Theophanes).

References

Sbeinati, M. R., R. Darawcheh, and M. Monty (2005). "The historical earthquakes of Syria: An analysis of large and moderate earthquakes from 1365 B.C. to 1900 A.D.", Ann. Geophys. 48(3): 347-435.

Guidoboni et al (1994)

(250) 9 March 757 Habura, Mesopotamia, Palestine, Syria

sources 1

Theoph. 430
[Dion. Tellmahr.1 2.216

sources 2

The Great Chronogr. 12

literature

Payne Smith (1879)
Russell (1985)
Whitby and Whitby (1989)

catalogues

von Hoff (1840)
Mallet (1853)
Sieberg (1932 a)
Amiran (1950-51)
Grumel (1958)
Guidoboni (1989)

Theophanes records a strong earthquake in the year of the world 6248 [756-757 A.D.], during the sixteenth year of the reign of Constantine V:

In this year, a powerful earthquake struck Syria and Palestine, on 9 March.

Pseudo-Dionysius of Tellmahre reports collapses in three villages in Mesopotamia:

In the year 1067 [of the Greeks; i.e. 756 A.D.], on Tuesday 3 Adar [March], there was a great, violent and terrible earthquake at midnight in the land of Mesopotamia, and three villages near Habura collapsed. The many people who were there were crushed and perished, like grapes in the press, and many places were destroyed in the earthquake, which took place because of the great number of our sins.

It has not been possible to identify the site of Habura. The only indication provided by the editor of the text of Pseudo-Dionysius of Tellmahre is a reference to the Thesaurus Syriacus (Payne Smith 1879, I, co1.1172), which laconically reports: "name of a city". For problems of dating the sources, see Whitby and Whitby (1989, p.197).

References

Guidoboni, E., et al. (1994). Catalogue of Ancient Earthquakes in the Mediterranean Area up to the 10th Century. Rome, Istituto nazionale di geofisica.

Taher (1996)

130/747 : earthquake in Châm, in the month of Ramadan (month of May). Several seismic tremors; the most violent earthquake is in Jerusalem; the western and eastern parts of the Dome of the Rock were damaged; numerous victims including many transmitters of traditions of the Prophet (of Medinan origin). The caliph Abû Dja`far al-Mansûr removes the silver and gold plates which covered the doors of the Dome of the Rock since the caliphate of `Abd al-Malik b. Marwan. Dinars and dirhams are minted which will be used to finance the reconstructions⁶⁶.

140/757 : earthquakes in al-Massîsa ; the surrounding wall is weakened. The caliph al-Mansûr decrees the reconstruction of al-Massisa under the responsibility of Djibrayl b. Yahya . The inhabitants of this town were few in number. The wall was rebuilt and the city was called al- Ma`mûra . The construction manager builds a large mosque. He paid the wages of 1000 workers⁶⁷.

158/774 : second earthquake in Jerusalem under the caliphate of al-Mahdî; reconstruction of the Dome of the Rock; the architecture was modified: al-Mahdî had it rebuilt lower and wider⁶⁸.

Footnotes

66 Al- Dhahabî , Târîkh al-Islâm, 5/39, 40; Al-`Ulîmî , al-Uns , 1/237, 238.

67 B. al-Athîr , al-Kâmil , 5/500. This is the ancient Greek city of Mopsuestia, cf. Honigmann , EI, t. III, p. 591-596.

68 Al-'Ulîmî, al-Uns , 1/282, 283.

References

TAHER, M.A. (1996) "Les grandes zones sismiques du monde musul-mans a travers l'histoire. I. L'Orient musulman," Annales Islamologiques 30 (1996): 79-104. - open access

Taher (1979)

140 A.H./757 AD

Al Mansûr¹ decreed the reconstruction of Al-Maççiça² under the responsibility of Djibra'il ibn Yahya. The surrounding wall had been weakened by the earthquake. The inhabitants of this town were few in number. The wall was rebuilt and called Al Ma'mura. And the head of work built a large mosque. He paid the wages of 1000 workers. It allowed many inhabitants to settle inside the enclosure.

Footnotes

1 Abu Dja'far, the 'Abbasid caliph, see Ibn al Athir, al Kamil, 5/500.

2 This is the ancient Greek city of Mopsuestia, located on the right bank of the Djaihan River. Cf. Honigmann, E.I., t.III, p.p. 591-96.

References

Taher, M.A. (1979): Corpus des texts arabes relatifs aux tremblements de terre et autres catastrophes naturelles, de la conquete arabe au XII H/XVIII JC, Ph.D. Thesis (Univ. Paris), 337 pp.

Abou Karaki (1987)

* 756 A.D. calculated date ?

In Syria and Palestine, a strong earthquake, (Will).

Between 758 and 775 AD., in Palestine and Syria, in Jerusalem, Aleppo and Antioch, destroyed buildings; strong enough

765 (May 3) AD, felt in the North of Syria, damaged buildings in Jerusalem, earthquake associated with faults in the 30.8° N - 33.6° N zone, M_L = 6.2 (BM1) which refers to the descriptions of (Will) above, among others.

765 AD Jerusalem, the damaged AI-Aqsa Mosque (BM1)

757 AD, 140 AD, the city of Misis, I = VII, (PTAH).

In the year 140 AD. H, the walls of the city of Misis, which were in poor state because of the earthquakes, were restored by the caliph AL-MANSOUR, and the city was renamed AL-MAMOURAH (TAHA)., NAJA: J = in the interval (23 MAY 757- 13 MAY 758), i.e. the period which corresponds to the year of restoration of the walls, 140 A.H.

French

* 756 apr. J.C date calculée ?

En Syrie et en Palestine, un fort séisme, (Will).

Entre 758 et 775 apr. J.C., en Palestine et en Syrie, à Jérusalem, Alep et Antioche, des immeubles détruits; assez fort

765 (le 3 mai) apr. J.C., ressenti au Nord de la Syrie, immeubles endommagés à Jérusalem, séisme associé aux failles de la zone 30°,8 N - 33°,6 N, M_L = 6,2 (BM1) qui se réfère aux descriptions de (Will) ci-dessus, entre autres.

765 apr. J.C. Jérusalem, la mosquée AI-Aksa endommagée (BM1)

757 apr J.C., An 140 apr.H, la ville de misis, I = VII, (PTAH).

En l'an 140 apr. H, les murailles de la ville de misis, qui étaient en mauvais état à cause des tremblements de terre, furent restaurées par le calife AL-MANSOUR, et la ville fut rebaptisée AL-MAMOURAH (TAHA).,

NAJA: J = dans l'intervalle (23. MAI 757- 13. MAI 758), soit la période qui correspond à l'année de restauration des murailles, 140 apr. H.

References

Abou-Karaki, N. (1987). Synthèse et carte sismotectonique des pays de la bordure Orientale de la Méditerranée: sismicité du système de foilles du Jourdain – Mer Morte, University of Strasbourg, France. Ph.D. Diss.

Russell (1985)

The Earthquake of March 9, 757

The earthquake of 757 completes the present analysis of earthquakes in Palestine and Arabia through the mid-8th century. Theophanes wrote of this earthquake, In this year, an earthquake. by no means mild, affected Palestine and Syria on the 9th day of the month of March (1839: 662-63). The year referred to was A.M. 6248, which dates the event to March 9, 757.

Further textual documentation of this earth-quake has not been found. Cedrenus, for example. did not record any events at all between June 754 and June 759 (1839: 10-11). Even so, the temporal proximity of this earthquake to Theophanes' own lifetime (ca. 758-817), coupled with his general accuracy and consistency in documenting earlier earthquakes, suggests that sections of ancient Palestine and Syria were indeed affected by an earthquake on March 9, 757, provided that his dating is correct. Whether the Negev, the Jordan Valley, or the regions east of the rift were affected as well cannot be established from this text. No archaeological evidence has yet been correlated with this earthquake.¹⁶

Footnotes

16 In addition to destructions in 748 and 757. the region of Syria also experienced earthquakes in 713 and 717 (Theophanes 1839: 587. 614: Ambrasseys 1962: 77). The first half of the 8th century also saw the rapid decline of the Omayyad Caliphate (Hitti 1951: 527-32). The last Omayyad Caliph, Marwan II (744-750), even transferred the seat of government from Damascus to Harran (Hitti 1951: 529), probably as a result of frequent earthquake destructions and the growing discontent of his subjects. As previously observed for the disastrous earthquakes of the mid-6th century. the social and economic impact of earthquakes in the early 8th century has yet to be incorporated into our understanding of early Islamic history.

References

Russell, K. W. (1985). "The Earthquake Chronology of Palestine and Northwest Arabia from the 2nd through the Mid-8th Century A.D." Bulletin of the American School of Oriental Research 260: 37-59.

Russell, K. W. (1981). The earthquake chronology of ancient Palestine and Arabia from the 2nd to the 8th century A.D. Anthropology. Salt Lake City, UT, University of Utah. MS.

Cometography Comet Catalog

reproduced with permission from Gary Kronk (personal communication,2024)

1P/760 K1 (Halley)

Discovered: 760 May 15.8 (A=0.94 AU, r=0.59 AU, Elong.=35°)
Last seen: 760 July
Closest to the Earth: 760 June 2 (0.4105 AU)
Calculated path: ARI (Disc), PER (May 22), AUR (May 29), LYN (Jun. 3), CNC (Jun. 6), LEO (Jun. 8), VIR (Jul. 10)

The Chiu T'ang shu (945), T'ang hui yao (961), and Hsin T'ang shu (1060) provide virtually identical details of this appearance of 1P/Halley. The comet is referred to as a "broom star" when it was first seen on 760 May 16 "in the east between Lou [α, β, and γ Arietis] and Wei [35, 39, and 41 Arietis]." The date and location indicate a morning observation, implying a UT of May 15.8. The comet is described as white and about 4° long. The details acquired from the Chiu T'ang shu and Hsin T'ang shu were obtained from the astronomical chapters. It is interesting that the annals of these two texts say the comet was first seen on May 17.

The Chinese accounts say that it moved rapidly toward the northeast. It passed the Mao [the Pleiades], the Pi [α and ε Tauri], the Tsui-Hsi [γ and φ¹ Orionis], the Shen [α, β, γ, δ, ζ, and κ Orionis], the Tung-Ching [γ, ε, ζ, λ, μ, ν, ξ, and 36 Geminorum), the Yu-Kuei [γ, δ, η, and θ Cancri] the Liu [δ, ε, ζ, η, θ, ρ, σ, and ω Hydrae], and Hsien-Yuan [α, γ, ε, ζ, η, κ, λ, μ, o, ρ, and 15 Leonis, and α and 38 Lyncis]. It finally moved to the west of the T'ai-wei Enclosure, 7° to the west of Yu-chih-fa [β Virginis], and was extinguished. It lasted for a total of more than 50 days.

The details of the comet's final observation are interesting to examine. First, the statement that the comet remained visible for over 50 days indicates it was still under observation following July 5. Second, although the T'ang hui yao and Hsin T'ang shu say the comet passed within 7° of β Virginis, the Chiu T'ang shu says it passed only 0.7° away. Calculations using the orbit below indicate the comet never passed closer than 3.7° from that star and that this occurred on July 13.

The Byzantine monk Theophanes the Confessor wrote Chronographia around 813 and noted that during Annus Mundi 6252 (759-60), "a very bright comet appeared for ten days in the east and another twenty-one days in the west.".

The Arabic historian Agapius of Manbij (10th century) reported, "In this year the star with a tail appeared, and it was in Aries before the Sun, and the Sun was in Leo. It proceeded until it was under the rays of the sun, then went behind it and stayed 40 days." David Cook (1998) has suggested the observation was actually made by Theophilus of Edessa.

The first person to suggest that this comet was 1P/Halley was P. A. E. Laugier (1846). Although he did not compute an orbit, he said the orbit of that comet could fit the available Chinese observations if the perihelion date was estimated as 760 June 11. J. R. Hind (1850) investigated this apparition and agreed with Laugier's conclusion, right down to the date of perihelion. He said, "The return of the comet in 760 appears to me little short of a certainty." P. H. Cowell and A. C. D. Crommelin (1908) were the first to investigate the long-term orbital motion of 1P/Halley and concluded the perihelion date was 760 June 15. The modern orbital investigations of D. K. Yeomans and T. Kiang (1981), Werner Landgraf (1986), and G. Sitarski (1988) have included the effects of nongravitational forces and have almost unanimously determined the perihelion date as 760 May 20. Calculations using the Yeomans-Kiang orbit below indicate the comet reached at a minimum solar elongation of 2° on April 3 and a maximum solar elongation of 35° on May 17. On June 1 the comet reached another minimum solar elongation (18°), and on June 2, it attained its most northerly declination of +41° (apparent). It reached a maximum solar elongation of 54° on June 22.

T	ω	Ω (2000.0)	i	q	e
760 May 20.671 (UT)	99.997	44.687	163.443	0.58184	0.96785

ABSOLUTE MAGNITUDE: H₁₀=2 (Vsekhsvyatskij, 1964), 4.0 (Kronk)
FULL MOON: April 5, May 4, June 3, July 3

Sources

Chronographia (813), p. 597

Chin Tang situ (945), p. 171

T'ang hui yao (961), p. 171

Agapius of Manbij (10th century), p. 542

Hsin T'ang situ (1060), p. 171

Synopsis Istorion (1100), p. 464

A. G. Pingre (1783), pp. 336-7, 610-11

CR, 15 (1842 Nov. 21), pp. 952-3

CR, 23 (1846), pp. 186-7

MNRAS, 10 (1850 Jan. 11), p. 56

PMJS (3rd Series), 36 (1850 Jun.), pp. 471, 474

J. Williams (1871), p. 44

G. F. Chambers (1889), pp. 512-13

MNRAS, 68 (May 1908), pp. 510-14

PA, 42 (1934 Apr.), p. 196

Ho Peng Yoke (1962), p. 171

S. K. Vsekhsvyatskij (1964), p. 48

MRAS, 76 (1972), pp. 35, 53

R. R. Newton (1972), p. 683

CAA, 3 (1979), p. 122

D. K. Yeomans and T. Kiang (1981), p. 643

J. L. Brady (1982), p. 210

IBIS, 38 (1985), pp. 205-6

W. Landgraf (1986), p. 258

G. Sitarski (1988), p. 263

personal correspondence from David Cook (1998).

References

Kronk, Gary W. (1999) Cometography A Catalog of Comets Vol. 1 Ancient-1799: A Catalog of Comets 1 Cambridge University Press - not open access - Cambridge University Press

References

Williams, J. (2024). "Mid-8th Century CE Seismic Sequences Along the Dead Sea Transform." Annals of Geophysics 67(1): SE101.

Supplemental Appendices for Williams, J. (2024). "Mid-8th Century CE Seismic Sequences Along the Dead Sea Transform." Annals of Geophysics 67(1): SE101.

Description	Image	Source
Comet in Chronicle of Zuqnin	Fig. 1 Syriac text and drawing: The relevant Syriac text from the Chronicle of Zuqnın (finished AD 775/6) on the comet AD 760 (1P/Halley) – from the middle of the first line shown to the middle of the last line – with a drawing embedded in the text (Vatican Library, Vat. Syr. 162, folio 136v): the comet to the left, the three brightest stars of Aries (α, β, and γ Aries) in the center, and the planets Mars and Saturn as Ares and Kronos to the right, as identified in the Syriac caption. The drawing fits best for around May 25 given the relative position of Ares/Mars east (left) of Kronos/Saturn, both west of Aries. See Fig. 2 for a comparison with a computed position of 1P/Halley for May 25 at 0 h UT. Neuhauser et al (2021)	Fig. 1 - Neuhauser et al (2021)
Sky around 760 May 25 in the early morning	Fig. 2 A comparison with Fig. 1 shows that the original drawing is for a date around 760 May 25 in the early morning (2:40 h local time, 0 h UT): both Sun (NE) and Moon were under the horizon at that time, 1P/Halley was ~7° above the NE horizon. IAU constellations are indicated in black, the ecliptic in orange with dots at the borders of zodiacal signs. The planets Mars (0.7 mag, red dot) and Saturn (0.5 mag, yellow dot) are still close to each other. The position of the comet is indicated on our own new (green) orbit (and as grey cross on the old orbit, JPL, YK81); both orbits start on May 17. The drawing (Fig. 1) was not used for orbital reconstruction. Here and in all other figures, the comet plasma tail pointing away from the Sun is displayed, while observation and drawing regard the dust tail. This and all other such figures are drawn with Cartes du Ciel (v3.10). Neuhauser et al (2021)	Fig. 2 - Neuhauser et al (2021)
Horizon plot for Amida for 760 May 18 at 2:40 h local time	Fig. 3 Horizon plot for Amida for 760 May 18 at 2:40 h local time: The Chronicle of Zuqnın reported a white sign ... in ... Aries, to the north from these three stars in it, which are very shining ... before early twilight, the first dated position in Section 2 (Z1), to the north of α, β, γ Ari on the horizontal system. The comet with tail directed away from the Sun (in the NE below horizon) is indicated for May 18 at 0 h UT on the new (green) orbit (as grey cross on the old orbit). The expected positions on May 20.0 and 26.0 (UT) are indicated with green (and grey) tick marks. Our positional error box is shown in red, the relevant stars in Aries as red dots with their names, Mars as labelled red dot, Saturn yellow, and the ecliptic in orange. Neuhauser et al (2021)	Fig. 3 - Neuhauser et al (2021)
Horizon plot for Amida for 760 May 22 at 2:40 h local time	Fig. 4 Horizon plot for Amida for 760 May 22 at 2:40 h local time: The Chronicle of Zuqnın reported the comet to be in/at the initial degree of [the] second [sign] (i.e. Taurus) ... still in the same Aries at its edge/end/furthest part, the second dated position in Section 2 (Z2). This record constraints the comet position to be close to 30° ecliptic longitude (Taurus 0°) ± some uncertainty, estimated to be ±1.5° (from some other observations of the same author, see Section 2) – indicated here by orange dashed lines with ecliptic longitude λ given (ecliptic in orange). The comet was at this longitude range and also still in Aries (at its end); the end of Aries was built by 33, 35, 39, and 41 Ari, indicated as red error box, while the head of Aries and its surrounding is made up by α, β, and γ Ari. The comet is indicated for May 22.0 (UT) on the new (green) orbit (grey cross on the old orbit). The expected positions on May 20.0 and 29.0 (UT) are indicated with green (and grey) tick marks. Neuhauser et al (2021)	Fig. 4 - Neuhauser et al (2021)
Horizon plot for Amida for 760 June 1 at 2:40 h local time	Fig. 5 Horizon plot for Amida for 760 June 1 at 2:40 h local time: The Chronicle of Zuqnın reported that the comet was going bit by bit to the North-East direction until dawn of Pentecost in the night May 31 to June 1, the third dated position in Section 2 (Z3), the red error box. The NE direction is taken to be azimuth 45 ± 22.5°. The comet is indicated with tail directed away from the Sun for June 1 at 0 h UT on the new (green) orbit (as grey cross on the old orbit slightly below the horizon). On our new orbital solution, the comet was in conjunction with the Sun on June 1.8 (UT) with minimal elongation being 19.1° (according to the standard JPL orbit, it was on May 31.9 with 18.5° minimum elongation); the last observation before comet-sun-conjunction as reported in the Chronicle of Zuqnın for early morning of June 1 is consistent only with our new orbit regarding this inferior conjunction. The expected positions on May 30.0 and 31.0 (UT) are indicated with green (and grey) tick marks. Neuhauser et al (2021)	Fig. 5 - Neuhauser et al (2021)
Horizon plot for Amida for 760 June 3 at 20:30 h local time	Fig. 6 Horizon plot for Amida for 760 June 3 at 20:30 h local time: The Chronicle of Zuqnın reported that the comet was seen from the north-west [quarter] at the beginning of [the] third [day] after Pentecost ... at evening time (Z4 and Z5, Section 2), the red error box. The comet is indicated with tail directed away from the Sun on the new orbit (cross on the old orbit). Along our best fitting orbit of 1P/Halley the closest encounter of the comet with the Earth occurred on 760 June 3.6 (UT) with 0.37 au (according to the JPL standard orbit, closest approach was on June 2.7 with 0.41 au). The expected positions on June 2.74 and 4.74 (UT) are indicated with green (and grey) tick marks. Neuhauser et al (2021)	Fig. 6 - Neuhauser et al (2021)
Horizon plot for Chang’an (now Xi’an, China), the Tang capital, for the night 760 May 16/17 at 4 h local time	Fig. 7 Horizon plot for Chang’an (now Xi’an, China), theTang capital, for the night 760 May 16/17 at 4 h local time: The waning crescent moon is seen in Aries. The Chinese reported abroom [star] emerged east direction ... it was located in Lou, the first dated position in Section 3 (C1). Lou is here Lunar Mansion 16 (LM 16), the right ascension range from β Ari to 35 Ari (Wei is LM 17). The given East direction can be considered as azimuth 90 ± 45∘, so that the given right ascension range (LM 16) is constrained in the NE by azimuth 45°, but in the SE by the local horizon. The positional error box is indicated by blue lines. The star α, β, and γ Ari and 35, 39, and 41 Ari, which make up the asterisms Lou and Wei, respectively, are indicated as blue dots, but the asterisms are not meant here. Our new and the previous (JPL/YK81) orbits are shown as green and grey lines, respectively, from May 16/17 midnight onward to the east. We draw a comet with plasma tail directed away from the Sun (in the NE below horizon) for its position on May 16.86 (UT) on the new (green) orbit – and for the same date as cross on the old (grey) orbit. In order to illustrate the motion of the comet along both paths the expected positions on May 20.0 and 30.0 (UT) are indicated with green and grey tick marks, respectively; the ecliptic in orange. Neuhauser et al (2021)	Fig. 7 - Neuhauser et al (2021)
Equatorial plot showing the whole comet path for the AD 760 perihelion	Fig. 8 This equatorial plot shows the whole comet path for the AD 760 perihelion (north up, east left): borders of the Chinese lunar mansions (right ascension ranges) are indicated as dotted lines (numbers on top) always going through their determinative star. The Chinese asterisms Lou, Wei, Xuanyuan, and Taiwei east and west (with Youzhifa in Taiwei west) are shown as blue skeletons. The ecliptic is shown as orange line with dots every 30° to indicate the borders of zodiacal signs. The planets Mars and Saturn are shown in close conjunction for May 22 at 0 h UT, the waning crescent moon for May 16.86 (UT). The positions derived here for the comet (Table 1) are shown as coloured boxes. Our new orbit is shown in green, the previous (YK81/JPL) orbit in grey, both from May 17 at 0 h UT (in Aries, right) until July 15 at 0 h UT (in Virgo, left), comet positions are shown as comet symbols on our new orbit on the dates of observation, and as crosses on the old orbit; the software Cartes du Ciel v3.10 shows the plasma tail directed away from the Sun. We can see that on June 9.58 (UT), the comet is indeed in Xuanyuan. Tick marks are shown on the new orbit on June 14.0, 19.0, 24.0, 29.0, and July 10.0 (UT) showing that the comet slowed down and got too faint (Section 5). Neuhauser et al (2021)	Fig. 8 - Neuhauser et al (2021)
Keplerian elements for non-periodic solutions	Fig. 9 Keplerian elements for non-periodic solutions (eccentricity e=1): They can be compared to (and are fully consistent with) the parameter ranges for periodic solutions with semi-major axes 17–19 au (Table 2, Fig. 13) shown as grey data points with error bars in the upper parts of the graphs. Neuhauser et al (2021)	Fig. 9 - Neuhauser et al (2021)
Results from fitting the orbit	Fig. 10 Results from fitting the orbit: Correlations between the Keplerian elements, shown as light grey points, of all closed solutions found: perihelion distance q, inclination i, longitude of ascending node Ω, argument of perihelion ω, and perihelion time T (from top left to bottom). In the upper left, for q, we indicate the solar radius as dashed line. Since most solutions for perihelion distance q and inclination i cluster within small ranges, we can use these two to identify the comet of AD 760, see next two figures. Having identified the comet as 1P/Halley (Fig. 12), we constrain the solution to those with semi-major axes from 17 to 19 au as 1P/Halley – these are shown here as dark points, and the best fit among them as cross. For eccentricity e = 1, one can see the parameter range for non-periodic solutions. Neuhauser et al (2021)	Fig. 10 - Neuhauser et al (2021)
Results from fitting the orbit	Fig. 11 The cumulative distribution functions for q (left) and i (right panel) (all solutions as in the previous figure): The highest slopes (i.e. the peaks in the probability density distribution) are indicated by vertical dashed lines and are located at q ~ 0.60 au and i ~ 168° (i.e. retrograde). We use these values for identifying the comet (Fig. 12). Neuhauser et al (2021)	Fig. 11 - Neuhauser et al (2021)
Perihelion distance q versus inclination i.	Fig. 12 Perihelion distance q versus inclination i. the comet of AD 760 (as constrained to q ~ 0.6 au and i ~ 168°, Fig. 11, as diamond in the upper part) is compared to other presently known comets with values in the range of i = 155 - 180° and q = 0.56 - 0.64 au: C/1855 Ll (Donati) has a very uncertain period of about 252 yr, it was observed only for 14 days, C/1963 Al (Ikeya) has a well-known orbit, but was not visible in AD 760; the three other comets shown as circles in the lower center are unperiodic. For C/1992 J2 (Bradfield) and C/1896 Cl (Perrin-Lamp) there is no evidence that they have periods less than many thousands of years, the case is similar for C/2002 T7 (eccentricity e = 1.00048565(39), JPL 144, i.e. non-periodic). There are no comets with i = 170 - 180° in the plotted range for q. For comet 1P/Halley, we show the data pair for its perihelion in AD 1986 (plus sign) and all pairs from the orbital solutions in Yeomans and Kiang (1981) connected by a line (their data for perihelion AD 760 as plus), obtained from the JPL small-body database, precessed to 2000.0; the orbital elements from telescopic observations scatter more than those from extrapolation to pre-telescopic time. In the upper part, we show q and i of the best fitting solution for 17-19 au semi-major axes for the comet of AD 760: they are best consistent with comet 1P/Halley (YK81 did not specify error bars). Therefore, the identification of the comet in AD 760 as comet 1P/Halley is justified - for the first time for this perihelion only from historical data. Neuhauser et al (2021)	Fig. 12 - Neuhauser et al (2021)
Probability distribution of the Keplerian elements	Fig. 13 Probability distribution of the Keplerian elements as found in the semi-major axes range of 17–19 au. Small grey squares with error bar indicate the best fitting solution (Table 2). The distributions of the elements correspond well with the elements of the best fitting solution – within their uncertainties. Neuhauser et al (2021)	Fig. 13 - Neuhauser et al (2021)
Apparent brightness evolution for a usual comet	Fig. 14 Apparent brightness evolution for a usual comet, upper left panel: apparent brightness of comet 1P/Halley for our best fitting orbit during the perihelion passage AD 760 using Equ. 1 for usual comets with δ90 = 1 (Marcus, 2007a, 2007b) in the phase function. We plot apparent V-band magnitude m (in mag) versus date until mid July (the difference between our new orbit and the old YK81/JPL orbit in terms of estimated brightness is only ≤0.1 mag). We plot the estimated magnitudes for all ten published parameter sets of absolute magnitude H and activity parameter n listed in Section 5. The comet was brightest around conjunction with the Sun early June. The vertical dotted lines indicate the observing dates (Table 1). The grey shaded area (±1σ error range) around conjunction displays the estimated background sky brightness at the location of the comet according to our new orbit – consistent with non-detection in the night June 1/2 (and probably also 2/3) as reported in the Chronicle of Zuqnın and by Michael the Syrian. Two (horizontal) dashed lines are for 2 and 6 mag, which are the likely apparent brightness for first discovery (~2 mag) and last detection (~6 mag); assuming these two values and that both H and n would be constant during from first to last detection in AD 760, we fit H and n for this perihelion passage and obtain H = 4.49 mag and n=4.28 (bold dashed line) – but if we assume 5.5 mag for the last detection (very close to β Vir), we would obtain H = 4.08 mag and n=3.55 (dotted line). The fit from Broughton (1979) assuming first detection at 3–4 mag is shown as full pink line (one of the three bottom lines, H=5.7 mag, n=4.4). Apparent brightness evolution for a dusty comet, upper right panel: light curve as in upper left, but for dusty comets with δ90 = 10 in the phase function (Marcus, 2007a, 2007b). Our best fit with 2 mag at discovery and 6 mag at last is now H = 4.30 mag and n=4.08 (bold dashed line), and H = 3.90 mag and n=3.35 (dotted line) for 5.5 mag for the last detection. The comet is now almost 1 mag brighter, even better consistent with detection until May 31/June 1 and non-detection for about the next two nights. Elongation of comet 1P/Halley, lower left panel: The full line is for our new orbit, the dashed line for the previous orbit (YK81) – the previous orbit, where conjunction happened on 760 May 31.9 UT (dashed vertical line) is inconsistent with the explicite last detection on June 1.0 UT, as reported in the Chronicle of Zuqnın, but consistent with our new orbit, where conjunction is on June 1.8 UT (full vertical line). The first detection of this comet actually happened close to the maximal elongation (~36°) before perihelion passage. Brightening of comet 1P/Halley due to light scattering by dust, lower right panel: we plot the brightening m(Φ) (see Equ. 1) due to light scattering by dust for a usual comet (δ90 = 1, full line) and a dusty comet (δ90 = 10, dotted line). Neuhauser et al (2021)	Fig. 14 - Neuhauser et al (2021)
Transliteration of the Syriac text	Fig. 15 Transliteration of the Syriac text on the comet of AD 760 (see also Fig. 1 and Section 2). Neuhauser et al (2021)	Fig. 15 - Neuhauser et al (2021)
Chinese Texts	Fig. 16 The Chinese texts from JTS, THY, and XTS on the comet of AD 760 (see Section 3). Neuhauser et al (2021)	Fig. 16 - Neuhauser et al (2021)
Dated positions of the comet in AD 760 from historical observations	Table 1 Dated positions of the comet in AD 760 from historical observations (coordinates for epoch of date). Neuhauser et al (2021)	Table 1 - Neuhauser et al (2021)
Keplerian elements of our best fitting orbital solution	Table 2 Keplerian elements of our best fitting orbital solution for the AD 760 perihelion passage of comet 1P/Halley (heliocentric ecliptic J2000.0) – first our best solution, then the JPL orbits for AD 760 and 1986 for comparison, than finally our parameters for non-periodic solutions. Our solutions are based on six astrometric data points observed within a span of time of 50 days. The best closed orbit has χ²_red = 0.09, clearly indicating that the given astrometric and timing uncertainties are overestimated. Neuhauser et al (2021)	Table 2 - Neuhauser et al (2021)
Residuals (O-C) of the best fitting orbital solution	Table 3 Residuals (O-C) of the best fitting orbital solution of comet 1P/Halley for its perihelion passage in AD 760 with their significances, listed in brackets, which take into account astrometric as well as timing uncertainties (we give the modern names of the towns, where the comet was observed, see Table 1 Neuhauser et al (2021)	Table 3 - Neuhauser et al (2021)

756 CE BY NO MEANS MILD QUAKE(S)

March 756 CE

by Jefferson Williams

Introduction & Summary

Intensity Estimates

Textual Evidence

Archaeoseismic Evidence

Landslide Evidence

Tsunamogenic Evidence

Paleoseismic Evidence

Notes

References